Popular Science Monthly 1926-12: Vol 109 Iss 6

Page 1

Sipe toh, Late OF DISCOVERY AND INVENTION & GENE TUNNEY TELLS HOW HE BEAT DEMPSEY RY 7a Page 28 POPULAR SCIENCE MONTHLY, PUBLISHED AT 250 FOURTH AVENUE, NEW YORK

Page 2

New! The Now you can build models in colors! You’ve never seen anything like it, fellows! Look at the beautiful models on this page with their lustrous coloring —all made with the new Multicolor Meccano. Part after part gleams with brilliant colors, that’s why the models are so realistic. And all the fine engineering — for which Meccano has always been famous, is still there. We wanted the best colors we could find so we selected Duco, the same genuine Duco that is used on the finest automobile bodies —you'll probably find it on Dad’s new car. This gives a hard tile-like finish that does not crack or peel like ordinary paints. And Duco-finished parts cannot rust. Get the newest thing in construction toys. Building with Meccano is dead easy. No study required. Build your models in bright colors—flaming red for the Fire Engine, olive green for the Tank Car—only Multi- color ene gives you this, yet it costs no more. You'll certainly give the gang a surprise when you display your up-to-the-minute Multicolor outfit. No more colorless, dull models for you—be a leader! This is the day of the new Multicolor Meccano. There are sets from $1.00 to $45.00. Two dandy specials at $5 and $10 include motors. See them at your dealers. ‘Send for this Free Book! : It’s an interesting story entitled, “How Jack : t Discovered the Perfect Toy.” It will tell you 1 £ all about the new Multicolor Meccano. Sent ® free for your name and address and those of * three of your chums. Put No. K-2 after your 4 own name for reference. 7 . MECCANO COMPANY, INC., Div. K-2,, ' Elizabeth, N. J. é In Canada: Meccano Ltd., 45 Colborne St., Toronto : cae? ; nia Ca Ye é Special No. 3x Outfit —sLi6f Reduced to $10.00 A fine big outfit full of valuable parts for building hun- dreds of working models. Hasa powerful, reversing electric motor and big book showing how to make over 200 models. Sent prepzid upon receipt of price if not at your dealer’s. ai 2) i Model of Windmill built with the new Multicolor Meccano THE QUALITY eb 4

Page 3

POPULAR SCIENCE MONTHLY SUMNER N. BLOSSOM, Editor December, 1926 OAV E-IN?” soos By C. WHEELER A Stranger-Than-Fiction Story of Forty-Three Miners Who Were Rescued from Living Death T WAS noon on the fifth day of the recent Ironwood, Michigan, mine cave-in. For almost a week forty- three miners of Tom Trewartha’s gang had been trapped like rats in a hole, 726 feet down. Two cave-ins—tons of boulders and dirt tumbling down the main shaft of the Oliver iron mines—had blockaded the shaft above and below them. All the resources, men and mate- rials of the world’s most famous iron miaing district were concentrated on the desperate task of rescue. In dripping blackness two thousand feet below the surface, a wiry figure in rubber coat and boots was wrig- gling through a narrow burrow which had been dug upward from the twenty-fourth level. The man was George Hawes of Chicago, safety expert and volunteer rescuer. At his heels were two others—Oscar Olson, chief engineer of the mine, and Capt. Gust Erickson, mine superintendent. These three were working on the daring plan of reaching the impris- oned men from the bottom upward. They had made their way into the depths of the wrecked shaft by con- necting passageways from another shaft close by. Resourceful and skil- ful men they were, all three. Where the mole-like burrow now opened into the main shaft was a hole through which a man’s body could barely pass. Hawes, slim and agile, led the way. Squirming and twisting between jagged rocks, he forced his body through. Some- where, a thousand feet above him in the abysmal well, lay the living tomb of the forty-three. Could he climb up through the treacherous blackness and reach them? - Tze seeping from above splashed down in a cascade and drenched him. With chilled hands he clutched the rungs of a ladder that ran up one side of the shaft. The ladder was broken! By the light of his lamp he mended it with dangling cables and power lines that had been cut by falling debris. Cautiously, a foot at a time, he pulled himself upward, knowing that at any moment a false move might start tons of rock hurtling upon him. The other two followed. Up a hundred feet now; they had reached the seven- teenth level. Only the trickle of water down the shaft broke the ghastly silence. Hawes shouted. No answer from above. “We'll try to signal them,” he said. “Tf they’re alive they'll answer.” With a miner’s hammer he rapped on a water pipe that ran up through the shaft. One— two—three—seventeen blows. “Tf they hear that, maybe they'll guess it means we're on the seventeenth level,” After the Rescue Dazed and haggard from the shock of their five- day entombment—some of the forty-three Iron- wood, Michigan, miners as they entered the first- aid car following their miraculous escape. Once more scientific rescue methods had cheated death he said. He waited. There was no reply. “Nothing to do but keep on,” said Hawes. “The pipe may be broken above us. Let’s go.” GAIN he led the way up—as perilous a climb as ever human being at- tempted. Far above, the great shaft was still blocked with boulders. A single false. step might dislodge enough to bury the rescuers. Now and again a break in the ladder forced a halt while they improvised rope ladders to bridge the gap. Past the sixteenth, fifteenth, fourteenth levels, clutching and groping for a hold. The climb seemed endless. Now they approached the thirteenth. “Look!”’ Olson suddenly cried. A miner’s dinner pail, caught on the rocks, where it had fallen when the walls caved. It might mean any- thing or nothing. Again Hawes rapped the pipe with his hammer. One—two—three— thirteen counts. A pause. Then, clearly and distinctly, a tap in reply. Another! One—two—three—four— five—six—seven—eight! “They’re alive!” he cried. “They're signaling us from the eighth level!” Again he tapped “thirteen,” and again came the answering “eight.” “Thank God!”’ said Olson. O FAR they had climbed five hundred feet; there was another five hundred feet to go. Somehow they did it—pulling their drenched and weary bodies upward inch by inch, twisting and groping and clutching, until— “Hello!” A voice, the light of a miner’s lamp, a figure silhouetted against rock, and in another second Hawes’ icy hand was seized in the iron grip of Tom Trewartha, who stood, a sentry, at the entrance to the eighth -level. “We're all safe,” were the first words of Trewartha. Two miners stood beside him. “The other forty are a thousand feet back in the level, asleep.” He led the way into the cavern, arousing his men with a shout. Wild with joy and relief, they crowded 9

Page 4

POPULAR SCIENCE MONTHLY Scene of the Disaster View of Ironwood mining district. is in the middle distance. ‘about the rescuer, hugging him and pounding him onthe back. They showed him about their prison and described how they had lived for five terrible days. Trewartha, they said, had saved them from their greatest peril, the peril of de- spair and madness, by making them work. Drinking water they had found coursing down the mine runways. Their only food, after the scraps in their dinner pails were gone, had been birch tea made from bark peeled from timber props, brewed in a tobacco can. One man, famished, had devoured three corncob pipes. “The taste of tobacco was in them,” he said, “‘and I wanted a smoke.” Luckily, for light and fuel, they had found a drum of carbide for acetylene lamps, and a five-gallon can of kerosene. For encouragement, they had listened to the distant rumblings of rescuers’ blasts, to the grinding of the diamond drill, and had sung songs. What they wanted most now was _something to eat—and a smoke. Hawes fished down in his pocket and found a lone, battered cigar. He passed it around. They took turns puffing it. VERYONE recalls the thrilling rescue work that continued throughout that autumn afternoon and far into the night —how the flimsy ladders were repaired and strengthened, the emergency tunnel widened and braced; how nourishment and “‘smokes”’ were carried in to the forty-three famished prisoners; and then how, one by one, they were assisted down the perilous ladders and through winding passages to the bottom of the adjacent shaft, where they were lifted in mine cages to safety. The whole nation re- joiced with the relatives and friends who crowded about the mine entrance to cheer their men as they, came from the depths. One chapter of that story, however, The “G” shaft, where the cave-in occurred, Beyond is the ““H”’ shaft up which the miners escaped that most of us could only guess, has never been told. It was the wonderful part played by scientific and engineering genius in making possible one of the most remarkable and difficult rescues in min- ing history. Here was a sudden emergency that demanded the use of every precious second. It challenged the effectiveness of scientific training in mine rescue work first undertaken nearly twenty years ago by Uncle Sam’s Bureau of Mines. That the rescue was completed so thoroughly was due not only to the heroism of individuals who risked their lives, but to the fact that in the swift con- centration of engineering skill not one plan mis- carried. F YOU could visit one of the iron mines in the Lake Superior region and go down in a cage in one of the well-like shafts, you would realize something of the tremendous odds which faced the rescuers that Fri- day noon when the first alarm of the cave-in was brought to the mine en- gineers. You would find Ironwood, once a rough mining camp, now a city of 15,000 souls, nestled in the hills of the famous Gogebic range, for years the richest source of high grade iron ore. About a mile beyond the unpaved ore-tinted streets of Ironwood’s business cen- ter, you would come upon the Pabst mines of the Oliver Iron Company, the largest in the district. George Hawes, volunteer rescuer and safety expert, who, with two made the perilous climb leading to the prisoners December, 1926 Framework hoisting towers, rising from the hills, mark the entrances to mine shafts. Then, if you inquired where the rescue occurred, you would be directed to the “G” shaft—the main shaft of the work. ings. This, like its neighbors, is simply q huge burrow dug into the hill. It Zoes down to a depth of 2600 feet, cr nearly half a mile. Unlike an ordinary welj however, it slants at an incline of about seventy degrees. The sides of the shaft are heavily ribbed and braced with plank. ing and steel girders to withstand the tremendous pressure of rock. A’ INTERVALS of about 100 feet downward there extend from the shaft horizontal passages like the branches of a tree. These are the levels, Each level bears a number, the num. bers increasing in order as the depth increases. Thus the second level is near the top of the shaft, while the twenty. sixth level is at the bottom. From each level, in turn, branch still smaller tun- nels called *‘drifts.’’ In these drifts the miners work, digging out the ore, which is loaded into cars and transported along the level to the shaft. Up and down through the shaft, like the elevator in a skyscraper, runs the “cage” which carries the miners to and from their work on the various levels and which hoists the loaded skips of ore to the surface. It runs on tracks and is fastened to a cable from a hoisting engine above the surface. On one side of the ““G” shaft, about a quarter of a mile distant, another shaft of the Pabst mine pierces the earth. It is known as the ““H” shaft. Some of its levels connect with corresponding levels of the “G.”’ On the other side, at about the same distance, is a third shaft, known as the “F” shaft of the Aurora mine. Between this and the “‘G”’ shaft is an old abandoned “‘C” shaft of the Pabst workings. Such was _ the bewildering ant hill of tun- nels and passages that con- fronted the rescuers on the day of the disaster. HE first inkling of trouble came half an hour before the noon whistle on Friday, when the hoist- ing engineer at the “G” shaft became — suddenly aware that the cable sus- pending the cage had fallen slack. Something had gone wrong. Only a few min- utes before, three men, an electrician and two helpers, had gone down in that cage. : Quickly one of the skips used for hoisting ore was lowered. Before it reached the eighth level it stopped abruptly; and when the hoisting engine tried to lift it out again, the cable snapped. The skip was buried. The meaning was all too plain—a cave-in! Instantly warnings were flashed to the miners work- ing on the various levels below. They escaped others, —=ew © eae fe Boo

Page 5

December, 1926 he levels leading into the ““H” es but forty-six. Of these, three had been hurled to probable death in the cage; the remaining forty-three were trapped in a walled dungeon of rock. The extent of the tragedy now was re- vealed. Something—it might have been the effect of an earthquake months be- fore, or of recent heavy rains, or the jarring of a derailed mine car—had dis- lodged a huge boulder. Tearing through the shaft wall, the great rock had plunged downward, crashing at the eighth level into the cage and breaking it loose from its cable. The cage with its human cargo had hurtled 1900 feet to the bottom of the shaft, followed by a shower of boulders. The pounding of the boulders j had caused the two cave-ins, one at the eighth level, the other at the twenty-first. ETWEEN these two walls of debris were imprisoned the forty-three. Of these, forty were miners at work on the eighth level under the shift boss, Tom Trewartha. The other three were shaft inspectors, known in the mine as “road monkeys,” two on the thirteenth level and one on the eighteenth. Light wires, telephone wires and water pipes running through the shaft had been broken by the deluge. The entombed men were completely cut off from com- munication. Their only supply of food was what was left in their dinner pails. Trewartha was a boss of known courage and resourcefulness, with thirty-nine years of experience in the mine. He could be counted on. Yet, even with such a “Cautiously, a foot at a time, Hawes pulled himself upward. One false move might start tons hurtling down. Only a trickle of water broke the ghastly silence. He shouted. No answer from above” POPULAR SCIENCE MONTHLY il “Wt” PABST SHAFT RESCUED MEN HOISTED BY CAGE FROM 24™ LEVEL . TO SURFACE ABST SHAFT ee FT. DEEP 2,60: aan Prrrriiiiiiiiirii ts LADDER "G" 2s eve, Se eo LeveL SS RESCUE PARTY CUT WAY THROUGH THIS DEBRIS TO REACH SHAFT e° SG (aneeee > i ane How the Prisoners Were Reached The rescuers first to reach the entombed men dug a passageway. up to the shaft and from _ there climbed by ladder to the eighth level. The other three plans included dig- ging a new passageway down from above, drill- saeare * ee mn ne ing a hole to pass food, and tunneling up from a third shaft, the ““F’’Aurora leader, how long could they hold out in the battle with hunger and madness? It was a task that called for expert engineering and perfect teamwork. With- in a few hours the entire district was transformed from an industrial enter- prise into an organized army of rescue. Work in other mines ceased. More than three thousand men volunteered to risk their lives. The shift bosses lined up their men, and from them picked those who could be depended upon to stand up under the terrific punishment of driving physical labor. In all, about 300 were chosen. They were the “shock troops.” Every man of them possessed working knowledge of mine engineering. The scheme of attack was four-fold— first, to dig a new passage down through the mass of debris that blocked the shaft between the second and eighth levels; second, to drill a two-and-one-half-inch hole straight down from the second to the eighth level, through which food might be passed and communication established; third, to dig an upward tunnel, or “raise,” from the thirteenth level of the adjacent Aurora “F” shaft to the eighth level which held the prisoners; and finally, from the depths of the ““G”’ shaft, to bore other “‘raises’’ upward from the twenty-fourth level, paralleling the main shaft, and so pass around the lower cave-in. It was this last plan of working from the bottom up, the most difficult of all, that in the end succeeded. wo these plans were being exe- cuted, the first rescue squads, armed with acetylene cutting torches, were hurrying to the bottom of the wrecked shaft where the cage with its three passengers had plunged. Descend- ing by way of the “H” shaft, they groped across the twenty-sixth level until they came upon a shapeless and twisted mass of iron, half covered by dirt and rocks. No hope of any man’s surviving that awful crash. With torches the rescuers cut through the tangled metal until, at midnight, they recovered the bodies of their three (Continued on page 129)

Page 6

TSS Se 12 bs ad / POPULAR SCIENCE MONTHLY , O, BWANA, we will not go with you after the gorilla. On the trail of the lion and the elephant, yes—we will follow where you lead. We will stand by you while you kill the rhi- noceros and the buffalo. But the Man-of- the-Mountains is crafty. Even the lion and the elephant shun the forests where he lives. We are afraid. We will not go with you to the Mountains of the Moon.” The all but naked “headman” de.iv- ered his ultimatum. The black hunters and warriors grouped behind him nodded in confirmation. “We will not go; we are afraid of the gorilla,”’ they chorused. The lean, leather-tanned white man stood up to address them. Alone, save for his train of native bearers, he had come more than two thousand miles into the heart of Africa with a single purpose. Here, on the edge of the land of the Pygmies, he was almost within sight of his goal. Eastward, towering above Lake Kivu, rose the volcanic peaks of the Kirunga mountains, and in the forests which lined their slopes lived the myste- rious man-beasts, the gorillas. To study and photograph them and if possible to capture them, he had crossed the Atlantic, steamed up the Congo river to the head of navigation, then followed the equator eastward through weary weeks, only to have his safari balk when its members had learned his true errand. FFERS of three, six, a dozen times their regular pay for hunting trips had failed to move them. At last, by bribery and persuasion, he had induced the chief of one of the local tribes to bring his best hunters and bravest warriors before him. Now they, too, refused to go into the gorilla country. They Captured Eight Gorillas—Alive Ben Burbridge, noted American big game hunter, on his two last expeditions to Africa captured more live gorillas than any other naturalist—eight in all—and has brought to America the only living gorilla outside of Africa. shown above with the little band of Pygmy warriors who formed his hunting party Burbridge is “What are you afraid of?” the white man demanded, speaking in the Swahili tongue, which is cur- rently understood throughout equatorial Africa whatever the tribal language may be. “What “It’s Brains Againg A Famous Big Game Hunte December, 19 Capture the ‘‘Beay The Only Gorilla in Captivity are you afraid of? The gorilla will not harm a man.” He tried to make his tone con- vincing. He might have succeeded Miss Congo, six-year-old gorilla brought by Burbridge from Africa, with her foster mother, Mrs. J. D. Burbridge, sister-in-law of the explorer. In this article Burbridge tells of the ingenious ruse he had to employ to separate the young gorilla from her parents with some groups of natives, but not with these. They knew better. The chief arose and came forward. Beside him limped a man who could scarcely walk. “The white man says the gorilla will not attack men,” said the chief. “Look at this man.” The lame one turned around and showed his back. Great chunks had been torn from his shoulders by the teeth of some wild beast. His knee was so twisted that he could never again straighten his leg. “A gorilla did that,” the chief ex- plained. “This man was cutting bamboo in the forest when the Hairy-one-who- lives-in-the-hills attacked him.” E TURNED and stalked away, his warriors following, back to their village of huts. Ben Burbridge, the gorilla seeker, was not daunted by this second setback. He was too experienced a hunter, both in America and Africa, for that. For twenty-five years this retired real estate man of Jacksonville, Florida, has been chasing big game of every variety be- tween Alaska and Mexico and all over Africa. But when the stalking of lions and elephants, Kadiak bears and jaguars, rhinos and buffalo, grizzlies and mountain lions began to be an old experience, he turned to new adventures which proved the most exciting in his whole career asa hunter,—the chase and capture of the gorilla. R. BURBRIDGE, in his two latest expeditions to Africa, not only ob- tained the only motion pictures ever made of the gorilla in its native haunts, but captured more live gorillas than have ever fallen prey to any other naturalist, eight in all. He succeeded in bringing three back to Europe and America alive, one of which, a female about six years old, has lived and thrived since the fall of 1925 in Florida and has furnished to scientists the first real opportunity to study the mentality of the beast which, both struc- turally and in reasoning powers, resembles man most closely. In the eighty years since a missionary found the skull of a gorilla and thus partly confirmed the truth of ancient travelers’ tales of a race of huge, manlike creatures who terrified their enemies by drumming upon their chests with their hands, not more than a dozen or so live specimens have ever been brought out of Africa, and only three of those were ever brought across the Atlantic to America. Most of them were tiny infants, of which only two lived more than a few days or weeks. Miss Congo, in her live-oak tree on the banks of the St. Johns River, is the only Decembe Te. Th Par livin fores of m shot not | ever of th N. Lr doul men desc still drec Hat sou the tra’ “hs cus got r

Page 7

r 194 Y) fer lst NK “ bo ie ee a ee a ae ee ae pecember, 1926 POPULAR SCIENCE MONTHLY 13 Brains— Fighting Gorillas!” Tells of Tricks He Devised to That Fights Like a Man’’ PARKER STOCKBRIDGE living gorilla today outside of the African forests. And up to 1905 there is no record of more than one gorilla ever having been shot by a white hunter; it is possible that not more than twenty white men have ever even seen a live full grown member of this strange race. gral up to a bare half century ago the very existence of the gorilla was doubted or denied by many scientific men, although the mysterious beasts were described and the name by which they are still known was given to them five hun- dred years before the Christian era. Hanno, a Phoenician navigator, sailed southward along the African coast about the year 500 B.c. In the record of his travels, Hanno describes a strange tribe of “hairy people” whose appearance and customs tally with what is known of the gorilla today. Then, for more than 2,000 years, the white world heard no more of the gorilla until, in 1590, an English sailor, Andrew Battel, came home from an African voy- age with the same tale Hanno had told. The gorilla was still a fanciful legend, however, until the discovery of a skull in 1846, of a complete skeleton in 1851, and of a skin, brought in to a missionary A Test of Intelligence Miss Congo showing the scientists that she can use her head to reach an orange—she piled the boxes up herself. Burbridge’s capture of Miss Congo is giving scientists their first real opportunity to study the mentality of a gorilla settlement by a native in 1858. But when Paul du Chaillu, the American explorer, pub- lished in 1861 an account of his African journey, in which he described the gorilla and its habits in detail and in the same volume told of a race of Pygmies, smallest of all hu- mans, who lived in the forests near the gorilla country, the yarn was too fantastic to be believed. The scientists of that day might have stood for the gorilla alone, but they could not swallow the Pyg my! So du Chaillu was branded as a liar and the gorilla as a myth along with the Pygmies, until later ex- plorers confirmed his ac- counts of both. Ben Burbridge, latest of these ex- plorers, has not only recorded the life of the Pygmies in motion pictures, but he has penetrated deeper into the thick mountain forests where the Kivu gorillas live than any white man had gone before. What he learned about the man-beasts and their way of living he has told graphically in a motion picture film entitled ‘“Burbridge’s African Gorilla Hunt,” just released as this is written. And one of the things he learned is that the natives who told him gorillas would attack humans were right. “T didn’t intend to kill any gorillas,” Mr. Burbridge told me, “but I did kill three, each time in self-defense as the beasts charged me. They charged many times, in fact, as I was making motion pictures of them, but usually I succeeded, with the help of my gun bearers, in frightening them off by a fusillade over their heads. ““Yes,”’ he went on, resuming his story from the beginning, “I finally succeeded in getting a sufficient number of natives, who were not too familiar with the ways of the gorilla, to make up my safarz into the mountains. - HAT I was after was live, young gorillas. In order to hunt them at all one has to have permission from the Belgian government, since they are found hardly anywhere except in the Belgian Congo. The permit that I had author- ized me to bring out four captives on each of my two expeditions, provided I gave one of each four to the Antwerp Zoological Gardens. **Our method was to watch for a family of gorillas passing through the forest, the old male leading and the young ones straggling along behind, and to pick up the straggling infants. It was not so easy The Beast That Fights with Brains Burbridge’s helper ground out this startling camera picture as the great gorilla rushed at the explorer as it sounds, and it was decidedly unsafe if the parents missed the youngsters before we were out of harm’s way. “The gorilla fears nothing when its young are in danger. The flesh-eating beasts seem to know that, and give the gorilla forests a wide berth. 77 HE only marauding beast which ventures into their haunts is the leopard, the stealthiest of all the cat tribe. The leopard is very fond of the flesh of baby gorillas and frequently man- ages to seize one and get away with it. Sometimes, however, the gorilla catches the leopard. A chief told me of hearing a commotion in the jungle one night, in which the roar of a gorilla and the scream of a leopard were mingled. In the morning he found a dead leopard, which had been literally torn to pieces. “IT had to devise many methods of exciting the curiosity or anger of the gorillas to get them to show themselves where they could be photographed, or to enable me to capture the young ones. The most successful was to imitate the snarl of a leopard, then change position rapidly when the mother gorilla charged in the direction of the sound, separating herself from her young. I would hold her atten- tion as long as I could in that way, while my helpers snatched at the baby gorillas and scuttled away to safety with them. “One day we caught two young gorillas in this way. We thought the rest had gone on, and had begun our march campward, when I heard the roar of a gorilla behind me. I know of nothing more terrifying than the roar of a gorilla when heard for the first time. It rivals the roar of a lion in volume, but has a more threatening tone. It is punctuated, moreover, by the beating of the beast’s arms against his chest, producing (Continued on page 132)

Page 8

GettINc THE TruTH in the new humane way. Dr. R. E. House, propo- nent of the famous “truth serum,” is shown above making a truth test at Windsor, Canada. The subject is placed in a reclining position and his eyes are bandaged in order to protect them against the light, as scopolamin, the “‘serum” used, dilates the pupils like belladonna crime. The crime “wave”’ has be- come a rising flood. Is there a remedy for this national dis- grace? I believe there is, and that science can help to supply it. The remedy is more prompt and certain conviction of the criminal. Science can aid this through the methods of practical psychology that reveal the innermost workings of the human mind. Consider, for example, the case of Andrew Toth, about which I recently read. On New Year’s Day, 1891, an aged watchman, Michael Quinn, was as- saulted in the mills at Braddock, Penn- sylvania, and killed. Andrew Toth was arrested. While he was being examined one of the men in the room fell over a cuspidor. Toth made the mistake of laughing. The man who fell immediately declared that he identified Toth as the person who had struck Quinn. Toth was convicted and sentenced to be hanged, but this sentence was commuted to life imprisonment. In 1911 a man named Stephen Toth, not related to the Toth who was in prison, died in Australia. On his deathbed he confessed to a priest that he, not Andrew Toth, was the murderer of Quinn. Andrew was released, minus twenty years of his life. Ne crime. is being disgraced by I BELIEVE that a psychologi- cal examination, in the hands of experts, might have revealed much that would have helped the jury judge the credibility of the convicting witness. It at least could have established definitely whether Andrew Toth was the kind of man to be a killer. POPULAR SCIENCE MONTHLY By E. E. Free Psychology has made enormous strides in recent years. Tests have been devised to measure the characteristics of human beings, so that their individual traits, abilities and weaknesses become evident. The minds of liars, for example, have become better understood. These methods are being used in business and in industry. When taxicab drivers in Chicago were selected by psychological tests, the num- ber of street accidents immediately decreased. Similar tests were used by Johnson O’Connor to select employees for the General Electric Company, and the labor turnover fell markedly. These same psychological tests can be In the White Glare of Truth Suspects being questioned by the “‘shadow box”’ method recently introduced in Los Angeles. They are walked onto a stage and power- ful lights focused upon them so that, while they can see no one, de- tectives can study them as they wish while they answer questions Recorpinc Heart Putsations, the plethysmograph above be. trays the emotional reactions of suspected persons when they are suddenly confronted with objects related to the crime. Its inventor, G. R.Salisbury, of Rochester, N. Y., is shown in the ~~ illustration above taking the chart from the roll at the end of a test - Strange New CRIME Remedies A Discussion of Amazing Devices That Test Skin, Eyes and Heartbeats to Detect the Guilty and Protect the Innocent used, as several remarkable recent devel- opments have shown, to study criminals and to extract the truth from witnesses, This is a logical next step in the applica- tion of science to problems of crime. Most large police departments already possess chemical experts who test bloodstains; microscopical experts who photograph the marks on a bullet and tell what gun it came from. These achievements are no- table and useful, but they deal only with circumstantial evidence. Science must now deal with the human evidence also; for the law insists, rightly enough, that human evidence always takes precedence over circumstantial. There are two ways in which psycho- logical science can help detect crime. One is by helping to determine when witnesses are telling the truth and when they arelying. The other is by elirmninat- ing from a list of suspected persons those for whom that particular crime would be a psychological impossibility. NE way to accomplish the first of these is by means of the much discussed “lie detectors,” which show, automatically, any attempt of a witness to lie. Some of these instruments record the heartbeats of the witness. A device is attached to the witness’s arm or chest. The witness then is asked questions about what he is supposed to know, or is shown objects related to the crime and which might arouse telltale emo- tions which the heartbeat ap- paratus would register. Thestrain and excitement of trying to lie usually causes a quickening of the heartbeats,

Page 9

ol. ils st S; 1e it st 5 it 5.4 ——S — -- oe ae Ce ec ee a i a December, 1926 Another instrument, devised by Dr. W. HI, Bates, an oculist of New York, meas- ures the exact shape of the witness's eye- ball from moment to moment. Dr. Bates has found that lying may create a bodily strain which tightens the muscles around theeye, and alters the shape of the eyeball. His instrument detects the alteration. A test of guilt or innocence which the psychological criminologists have found to be even more reliable depends on another bodily reaction which appar- ently is absolutely beyond the control of thesubject. This is the electric resistance of the skin. HE facts upon which this test is based Wicre been known to psychologists ever since the discoveries of Dr. Charles Féré in Paris, in 1887. That savant proved that the electric resistance of the skin alters whenever the subject experiences ary emotion. Many “‘lie detectors” and “emotion detectors” have been con- structed on this principle. The most re- cent and successful one I know of is that devised by a New York psychologist, Dr. David Wechsler. The apparatus is simple. The person to be examined dips two fingers into salty water in small porcelain jars. These provide the electric contacts. A small current, too feeble to be felt, is passed between the two jars and through the fingers. Meters connected with this cir- cuit measure the resistance of the skin. I sat recently in Dr. Wechsler’s labora- tory and dipped my own fingers into the two small cups. Dr. Wechsler adjusted the circuits and read the resistance of my skin, a figure which varies for different people and even for the same person at different times. This adjustment made, Dr. Wechsler suddenly reached over and pinched my chin. Instantly the light spot showing the reading of the galvanometer made a sharp jump across the chart. The pinch on the chin started off an emotional reaction, composed in part of surprise and in part of reaction to the mild pain. This emotional response great- ly reduced the resistance of the skin. The same thing happened when Dr. Wechsler blew an automobile horn, when he spoke of something that interested me, or even when I conjured up for myself a mental image of anything about which I was very much concerned. This alteration of the electrical resist- ance of the skin apparently is entirely independent of the will. Certainly it is so in my case, for the only effect which I produced by trying to prevent the mo- tion of the galvanometer was to make this motion still greater and to make it happen more quickly. Certainly in most examinations of witnesses the device would provide an invaluable, and utterly unconscious, index of how fully the wit- ness was emotionally disturbed from mo- ment to moment during the examination. S I write this article, the State of New Jersey is in the midst of its second in- vestigation of the famous Hall-Mills mur- der. Four years ago the Rev. E. W. Hall and Mrs. Eleanor Mills were found dead underneath a small apple tree outside the town of New Brunswick. Both had been shot. No one has been convicted, although the various investigations are reputed to have cost over two hundred thousand POPULAR SCIENCE MONTHLY *. GALVANOGRAM MOMENT OF EXCITATION TIME (SECONDS) The Skin Test These photographs show Dr. David Wechsler (right), New York psychol- ogist, making a test with his appa- ratus, which traps liars by measuring the electrical resistance of their skin under questioning. The person tested (below) has his fingers inserted in cups of salt water. The chart above shows the result of the test, the humps indi- cating plainly the subject’s reactions dollars. At the moment four persons are under indictment in connection with the crime, the arrests having been made nearly four years after the murder. Throughout the history of this famous case it has been believed by virtually everyone who has studied it that at least five persons know more than they have been willing to tell. This case would have been an excellent one in which to try some lie-detecting device like that of Dr. Wechsler. If one knew just which articles or questions were exciting and disturbing to the various witnesses, a theory of the crime would be easily found. The facts discovered psychologically might not ac- tually solve the mystery, but they would be sure to yield valuable clues. HIS emotional disturbance, while not, of course, a sure proof of guilt, is an important clue that can be followed up like any other clue. Like other clues, to be sure, it sometimes proves fruitless; but in any event it provides a new basis on which to sift the evidence of a crime. I remember, for example, one case in which a woman witness was being exam- ined by a lie-detecting device depending on the heartbeat. She was shown articles related to the crime. She was asked questions, all of which were passed by or answered without a quiver of the ma- chine. Suddenly, at the sight of some article which turned out later to have nothing to do with the case at all, the indicators on the machine showed great 15 excitement. The truth was that a mouse had peeped out of a hole in the flooring behind the examiner. The witness saw the mouse. Her heart instantly began to misbehave. Another procedure for eliciting the truth from unwilling or untrustworthy witnesses is the famous “truth serum” proposed a few years ago by Dr. R. E. House, a Texas physician. When a dose of this drug is given to a witness, he seems incapable of telling a lie. The truth comes out, whether the witness wills it to or not. HIS is not really a “serum” at all, but a well-known drug, named scopo- lamin, long known to physicians and used in the famous “twilight sleep” much dis- cussed a few years ago. One of the effects of this drug on the human mind is to paralyze what psychologists call the “‘cen- sor,” that continual watchfulness which guards everything you say and do and sees to it that you do not blurt out, on the spur of the moment, any foolish thing that happens to come into your head. In a sense, it paralyzes the will, including the will to deceive. In New Orleans, three newspaper re- porters took doses of the drug before the city medical society. They had agreed among themselves to try to lie. But when questioned, under the influence of the drug, the lies would not come. The truth Game out instead. Of course, the three reporters were pre- sumably men who were habitually truth- ful. Their natural impulses were to tell the truth. Many criminals are not like this. Either by nature or by long educa- tion and experience, lies come more easily to them than the truth. This is likely to affect their reactions to the Texas truth serum. Still, when properly used and in- terpreted, and especially when adminis- tered according to the careful technique worked out by Dr. House, the drug may be a most important aid to the discovery of truth. Like (Continued on page 145)

Page 10

sciatica ahaa aaa na et A ee ee en cr TST ee TA Te ee EEE 16 How a Hurricane Gathers Fury PF og go 7 SOME STORMS ORIGINATE AT a THIS POINT THIS HURRICANE WAS PROBABLY DEFLECTED WESTWARD AT THIS COLUMN SKIRTS BORDER y OF “HIGH™AT 125 ML. PER DAY POPULAR SCIENCE MONTHLY ene ar aa @ TROPICAL HURRICANES USUALLY OO eee =SKIRT EASTERN SEABOARD OF oF NORTH AMERICA UNTIL THEY ARE BEYOND THE BOUNDARIES OF “HIGH” WHEN THEY CURVE BACK N.E. AND EXPEND THEM- SELVES IN. ARCTIC REGIONS HW TROPIC ATMOSPHERE ALWAYS — TENDS TO. DRIFT AWAY FROM 0 oan, " (QUATOR BUT "HIGH" EXPANDED WHIRLING COLUMN EVENTS STORMS FROM 2 WINDS FROM ALL DIRECTIONS OF HEATED AIR HAS RISEN FAR ENOUGH INTO UPPER ATMOSPHERE TO ESCAPE : 3 SURFACE PULL OF EARTH'S 3 ae ROTATION ~ THUS COLUMN 1S DRAGGED WESTWARD December, 19% 7 ARE, hema SUN HEATS THIS AREA, Y EXPANDING AIR | UPWARD Cue DRAWN INTO HEATED AREA Be wie ee DUE TO ROTATION OF EARTH E RD- THESE WINDS EXERT A “COUNTER- CLOCKWISE” MOVEMENT ON HEATED AREA ° ie. STORMS RISING SOUTH OF THE EQUATOR WHIRL “CLOCKWISE” Wind and Rain, Spinning Like Top at 100 Miles an Hour, Wreak Havoc a grim reminder of the ever-present danger in a country subject to hur- ricanes. Within the last few years exten- sive studies have been made of these tropical storms and on this page our art- ist summarizes pictorially some of our lately-acquired knowledge of hurricanes and their habits, based on the work of Charles L. Mitchell of the U. S. Weather Bureau. The West Indian hurricane, taking its name from the center of its native region, is not the largest of storms, being midway between the mild cyclonic storm of the temperate zone and the havoc-wreaking tornado. A full-fledged hurricane is a whirling mass of wind and rain from fifty to 200 miles in diameter, spinning at the furious rate of a hundred miles an hour, with a partial vacuum in the center, and moving like a giant top creeping along a Pee eri rom recent disaster serves as Casino at Miami Beach, Florida, and wreckage of approach to million-dollar pier, after the Stronger built buildings, experts say, lessen damage when cyclones occur recent hurricane. smooth table at a rate of ten or fifteen miles an hour. It commences as a heated mass of moist, stagnant air rising by its own lightness. An incipient hurricane north of the equator will draw winds from both north and south; where the edges of these two air streams meet, a whirlpool of air is set up, rotating in the opposite direc- tion to the hands of a clock, as will all hurricanes north of the equator. August, September, and October are the hurricane months. During that time conditions giving rise to hurricanes are just right in the doldrums, a region of calm air near the equator. Since the universal equipment of ves- sels with radio, shipboard observers are able to keep the Weather Bureau con- stantly informed of the location and progress of hurricanes. Warnings are flashed to ships and the alarm is spread on land. Even a few hours’ advance notice helps lessen the damage done.

Page 11

ber, 19%, y me are of are n- nd on ice POPULAR SCIENCE MONTHLY 17 What Science Knows About Your Feet and Your Shoes Vanity and Overtaxing Are Chief Causes of Common IIls the production of a motion picture, I stayed for several weeks at the Athletic Club in St. Paul, Minnesota. There was a fine gymnasium there, and I welcomed the opportunity of “working Frter years ago, while supervising - out” on the track for a half hour each morning. It had been years since By Joun Amip average man, conscious of his strength and good general health, thinks he can walk when and where he likes without bad effects. Take orders from his own feet? He scouts the idea. As a ger. They feel that no harm will come from eighteen or even thirty-six holes of their favorite game on the one day a week they get a chance to play it. Asa result, instead of lowering their scores, they frequently lower their arches. A golf professional of my acquaintance who once overtaxed his feet in this I'd been able to do any regular *; way had to play for three years athletic work, and as I started out the first morning the physical director warned, “Look out you don’t overdo it!” “Don’t worry!” I told him. “Never felt better in my life!” Ifelt pretty cocky. My wind was surprisingly good. My heart was sound. I found I could run almost as easily as when I was at school. Around and around the track I went. Except that my feet hurt, I seemed to be as good as ever. When I stopped running, how- ever, my feet kept right on hurting. When they continued to hurt all day, and kept me awake that night, and kept right on hurting the next day, I had plenty of time to realize that something was really wrong— that the physical director’s warning hadn’t been so foolish, after all. Pain is the poor foot’s protest against abuse. Disregard that pro- test too long, and the feet will quit altogether. I wish somebody had told me this before I made that run. I've paid for my ignorance ever since with pain from fallen arches. I had not been doing a great deal of walking. Pounding around the hard-padded running track put un- Ten Causes of Foot Trouble 1. Sudden breakdown of foot muscles, due to unaccustomed use after long inactivity. 2 General aversion to walking. 3. Long hours of standing, as in cases of teachers, policemen and clerks. 4. Overloading—fat people seem often cursed with small feet. 5. High heels persistently worn. 6. Any illness that leaves the body in a weak- ened condition. 7. Local injuries that cause bad foot habits, such as turning the foot to ease a hurt toe. 8. Shoe salespeople who don’t know their jobs. 9. Incorrect walking—“toeing out.” 10. Vanity—which compels at least half of us to buy shoes too short and tight, to create the illusion that we have “small feet.” in specially made kid shoes with rigidly built arches as a penalty. Feet can be broken down by over- loading—fat men please note. Even well-developed, hardened feet can be broken down by being used be- yond their strength, or by long hours. Here’s where policemen suffer, pounding the pavements all day or all night. Here is where clerks and salesmen and office em- ployees suffer; for standing on the feet is almost as great a strain as walking on them. Nurses, too, know the agonies that use of the foot beyond its strength can give. UTOMOBILES have §substi- tuted hard concrete or asphalt surfaces for the uneven roads and foot paths of thirty years ago. This is another cause of modern foot troubles. Rubber heels have given some relief from the constant hammering, but it has been only partial. A manual on foot care and correct shoe fitting, prepared for officers of the U.S. Navy and U.S. Marine Corps, says: “The great majority of recruits received in the service for training due strain on the weakened arches of my feet, and they broke down. When we went to war the medical examiners found that one man in every eight passed upon had fallen arches. And the “young male population” of the draft constituted the strongest class of men, physically, in the nation. Older men are far more likely to have fallen arches or other foot troubles than young men. Among wom- en, defective feet are still more common; women are even proud- er than men of having feet that are small and painful. O WE can estimate that at least one person out of every five or six in this country is definitely suffering from weak or painful feet,—in round num- bers, between 20,000,000 and 25,000,000. And how those feet do hurt! Aching feet have spoiled more lives than aching hearts. As in my own case, undue strain is one of the chief causes of broken-down arches. The The Marvelous Mechanism That Enables Us to Run, to Kick, matter of fact, a single long walk, after months of comparative inactivity, can do serious damage to your feet through breaking down arch muscles un- accustomed to such protracted strain. Business men who play an occasional game of golf often fall victim to this dan- or to Dance SCAPHOID BONE There are twenty-six bones in your foot, connected by four times as many ligaments and operated by many muscles and nerves. Above is the sagittal section of the foot. The lined portions indicate muscles, and the dotted line indicates the principal arch. Through misuse of your feet, the arch may begin to sag and the bones slip out of place are men who were formerly occu- pied in sedentary occupations, ex- ercising little or not at all, and riding wherever possible. This universal aver- sion to walking is typical of the man of to- day who, surrounded by mechanical con- veniences of all types, saves himself the effort and takes the path of least resist- ance. This type of man will usually have under-developed, relatively weak feet.” MPROPER shoes are an- other cause of millions of fallen arches. The foot must not be choked to death. A shoe that fails to give room for the ball of the foot to expand, and for the toes to spread out, LOWER LEG BONE HEEL BONE at least to some extent, as the weight is brought forward in walking, is an “improper shoe.” A shoe that fails to distribute the weight properly in accord- ance with the requirements of the individual is an “improper shoe.” Tight shoes, short vamps, and high heels, used to give the highly valued appearance of

Page 12

18 brevity, are usually “improper shoes.” Just why the human race should become ashamed of its feet, except through neg- lect, it’s hard to say. In China gentle- women have bound their feet for centuries, to make them more ornamental and less useful. Never, since the days of sandals, has there been any widespread effort to strengthen and beautify the feet them- selves. The tendency has been always to stress the looks of the visible shoe, and neglect the foot itself, coyly concealed within. pe acre a good look at the position in which a woman’s foot is held by high heels, throwing the toe downward—and the eye upward. It tends obviously to shorten the Achilles tendon, the tendon at the back of the foot, that is straight when the heel is flat on the floor. This is one of the gravest charges against high heels. Sooner or later tendon troubles are almost sure to result. Incidentally, high heels do away entirely with the long, free, healthy stride of a heelless walk. But proud shoes are by no means limited to women. An examination of several thousand rookies at the Quantico, Virginia, Marine Station, for example, showed that four out of five were wearing shoes too short for them. As a test some time ago, all the men in a battalion of United States infantry were allowed to select shoes for themselves. Even Healthy Feet Will Benefit by This “Toeing the bar’ con the rung of a chair, to develop the pedal strength that walking should give but which, nowadays, too much riding in automobiles, street cars or buses is robbing us of Then they were sent on a practice march. They marched eight miles, camped twenty-four hours, and returned by the same route. On the first day thirty per- cent, and on the last day thirty-eight per- cent of the men were found to have severe foot troubles. : Later, shoes were selected by army doctors for that same battalion. A march of 120 miles was made in nine days, and not a man failed to complete the trip because of foot trouble. NOTHER cause of fallen arches is found in local injuries. A young banker whose hobby was basketball played forward on one of the teams in the local league of a New Eng- land city. One evening during the last minutes of an exciting game, the man who was guarding him slipped and fell. The banker, stumbling against his antagonist, sprained a toe. The toe didn’t prove to be seriously injured, and a doctor, looking at it, said it would soon be all right. But during the following weeks, to keep the toe from hurting, the banker threw his POPULAR SCIENCE MONTHLY | What Does Your Footprint Show? Left, pedograph (foot imprint) of a normal foot, shcwing good arch and toe line. Center, flat foot; and, right, the opposite extreme of abnor- mally high arch, sometimes called hollow feet weight on the inner edge of his foot, and before he realized it he was started on the way to having a turned-out foot, which specialists recognize as a forerunner of most foot troubles. A long siege with weakened feet came as a result of sprain- ing that toe. General disease or prolonged physical weakness may mean fallen arches that give trouble years after the disease or weakness that caused them has passed away. After such an illness as typhoid, while the whole body is still in a weakened condition, it’s easy to strain the feet. Flat feet are likely to follow nervous prostration. Similarly, indigestion and fallen arches are closely allied. FTER my feet were down, I went through the miseries of the damned. At times the pain shot clear up to my hips, like acute rheumatism. Yet, the steps necessary to effect a cure were com- paratively simple, if I had known them. And it was a surprisingly long time before I found anyone who did. “Put in arch supports,’ recommended the first physician I went to. ‘That will end your troubles.” But it didn’t end them at all. I put in the supports and my feet hurt worse than ever. I know now the trouble was that they didn’t fit properly. They were too high for my particular trouble. Also, I know now that, even if they had given me relief, they couldn’t in themselves have effected a cure. For a time I got relief in an unusual way. I was supervising another motion picture, in the White Mountains of New Hampshire. For days to- gether we worked above tree line, making our headquarters at the hotel on top of Mount Washing- ton. The uneven going on the peaks necessitated constant bal- ancing, shifting weight, jumping and all the rest that rough moun- tain going provides. A lot of our work was done among rocks where there was no trail at all. Though my feet protested stren- uously the first few days, I was exercising muscles that needed stimulation, and they were in better condition after the two weeks in the hills than they had been for months. But my first lasting relief from the foot pains came when I got a particular make of remedial shoe, with a low arch support that exactly fitted my foot. The morning. December, 1926 relief was almost instantaneous. hardly believe it possible. T could To get a properly fitting shoe may be sound easy—but it’s not. Shoes of the _ canal boat order aren’t necessarily the ¢ right shoes. You don’t cure feet just by _ making them look ugly. There shoull : be a good bearing surface, distributj ' the weight evenly. There should be full room for the toes. Toes are naty. rally playful, and like to wiggle. ps good for ’em. In addition, there should be support for the arch—great or small according to the requirements of the individual; and gs port for the heel and correct position of the foot as a whole. m One of the most important points in fitting shoes correctly is that the “break” of the shoe sole should correspond with the break of the “ball points,”’ the front corners of the foot tripod, behind the toes, in the flexion of the foot when the weight is brought forward. OST shoe manufacturers realize, far more than their customers, how important it is to fit shoes properly. Practically all stores find difficulty in securing salesmen to fit shoes correctly, And no matter how good the shoe may he or how honorable the intention of the manufacturer, placed on the wrong foot it will cause trouble. A woman entered one of the remedial shoe salesrooms in New York City. She had a long narrow foot. The salesman showed her a “‘common sense”” last, a little broader than her foot and with a low heel. She complained that it did not hold her foot firmly under the instep and that she preferred a higher heel. The salesman smiled wisely. He explained that the foot must have plenty of room, and that high heels almost invariably make trouble. The customer, a little doubtful, finally accepted his judgment and walked hope- fully from the store, wearing the “‘ com- mon sense” shoes. But instead of relief she got only more pain, in generous doses. Concluding that the first concern had done its best and failed, she tried another make of “‘comfort shoe”’ and obtained re- lief. In her particular case a firm, snugly fitting instep was needed to support the rather weak arch in her long foot. Also, she happened to (Continued on page 131) To Strengthen Weak Feet— Rise cn your toes, barefoot, twenty times night and Practice walking with a marble between your toes, When you sit, cross your feet for relaxation

Page 13

uld — lay 4 the — the by | mg be — tu- It’s for the Ip, of . = AM photos courtesy E. P. Dutton, & Co. 4 A bull moose takes its own picture in New Brunswick, ” Canada—with the help of a trip-wire trap cunningly set mn es, ht ar Ww ly. in Vv. : i Own Picture, he ot NOTED amateur photographer, A wanting some good pictures of al squirrels, laid hickory nuts on he rocks in a wood near his home. A gray si, squirrel, promptly finding them, for sev- * eral days thereafter visited the rocks . regularly twice a day. With that habit fixed, the photographer next attached a d nut to a trip wire, twisted tightly around ‘| a groove in the nut, the wire attached to ad the camera so that when the squirrel a should nibble, it would take its own ) picture. ; i * With its first quick unsuspecting nibble, 5 the squirrel set off the flash, and a fine af picture was the result. But thereafter of the photographer got no more pictures by this method. The squirrel knew] what ‘ was coming, and its nervous, quick move- ment, when the explosion occurred, pro- ‘ duced only a blur on the plate. More- f over, after twenty more attempts, it 3 learned how to_ get the nut without . causing an explosion. Each time it would timidly approach the nut, touch it with its nose, jump back as if the nut were red-hot, and then proceed expertly to free the nut without the slightest pull on the wire. Regularly, each day for a week, the squirrel came off the victor, without setting a single flash! The photographer finally had to get his pictures by building a blind, concealing himself in it, and operating the flash by pressing a push button. ASCINATING and surprising are the tales told of the always exciting, sometimes dangerous, work of the photog- rapher whose thrill it is to trick the wild things into having their pictures taken, The inhabitants of forest and field, water and air, are less willing to face the camera than humans, and those who make out- door photography their profession or hobby have to be more wily than their quarry. Some of the secrets of these hunters, who find the camera more excit- ing than the gun, have recently been told by William Nesbit, the photographer who POPULAR SCIENCE MONTHLY Raccoon nibbling at bait, setting off flash behind camera. operated by a second flash simultaneously with the above, took this picture A Camera Hunter Jel/ls His Secrets A second camera, How You Can Trick a Squirrel into Taking Its or ““Catch’’ a Woodpecker in Action figured in the squirrel incident above, in his fascinating new book, How to Hunt with the Camera. Many of the best animal pictures are taken with flashlight snares. Flash lamps are connected to wires stretched across a trail or baited, so that when the animal takes the bait he fires the flash powder and takes his own picture. A second camera and second flash are some- times so placed that they will photograph upon one plate not only the flash from the first lamp, but the animal setting it off. Anyone can set this sort of trap and SOFT IRON PLUNGER a ttt: ZZ MAGNET COIL ALUMINUM HAMMER Ressgeseeecer cess | (ramawrwrewntssanr re , SHUTTER RELEASE PITIIII La Saar AN att Site + + SS rc creree Seecere Oy SSS Khia Series ~~ ww L275 Tripping the Shutter Rainproof electric magnet (above) used by Mr. Nesbit for tripping camera shutter. At right: Sectional view The gray squirrel surprised into taking its picture. Then it outwitted the photographer probably “catch” something right near his own home, says Mr. Nesbit, for -more small animals roam about at night than most of us know. Skunks, raccoons, opossums, rabbits, are the commonest prowlers. ‘ Most of these animals fall for a cheese sandwich bait. Mr. Nesbit cuts small pieces from the sides of the cheese so that the cheesecloth will be on the two outer sides when folded together. Then wire is wrapped around the sandwich, which is hung from an upright to protect it from mice. Sometimes animals are lured into the “studio” by a bait line, leading in that direction. A trail of salt or vege- tables is especially enticing. OR, an artistic background for the animal to pose against as he nibbles the cheese sandwich, branches, ferns, even rocks, are arranged. Then the camera is fixed, pointed toward the place the animal is expected to occupy—twelve feet away for a small animal, twenty for a large. Animals, like celebrities, get used to the spotlight and come ‘back for more. One skunk returned to the same trap five nights running, not minding the flash and bang so long as he got his sandwich. Mr. Nesbit had to break a cat of the same habit by a load of salt fired into its whiskers when the flash went off. A sport of kings, affording tremendous thrills, is taking flashlight pictures of wild animals, especially deer and moose, from the bow of a boat at night. This is generally known as “flashlight jacking,” and is done mostly in June, July and August on lakes and streams having lily pads and grasses that game come to eat. The hunters go forth in a boat too steady to upset when the flash goes off. The darker the night the better, as the animals cannot see the boat behind the “jack.” This is any lantern that throws a single beam of light forward, none striking the boat. An electric jack with rheostat handle is (Continued on page 147)

Page 14

POPULAR SCIENCE MONTHLY December, 19% OG, snow, storms and forced land- ings are all in the day’s work for the air mail pilot. Below is Dean C. Smith, one of eight fliers who daily risk their lives on the New York-Cleveland route. He claims the dis- tinction of being the only air mailman who ever ran down a cow ITH the morning papers of September twenty-fourth scream- ing out that Gene Tunney was the new heavyweight champion of the world, and with ringside photographs of the championship fight miraculously appear- ing in Western dailies on the worst morn- ing-after in Dempsey’s career, there was probably not one among the host of readers who gave a passing thought to the men who had risked their lives to make the appearance of those pictures possible. Yet, so hazardous was the undertaking that of all the aviators who were sched- uled to fly over the Alleghenies and west- ward, bearing photographs of the bout, only two were able to penetrate the fog bank over the mountains and make their deliveries. They were Captain H. A. Chandler and Wesley L. Smith, air mail pilots. Alone, his only aids the instruments on his board, his only advice his own resourcefulness, each pilot battled sepa- rately with his unyielding adversaries, the elements. Fog and rain and darkness two hours of it without sight of earth, without a beacon or a landmark to guide them—flying blind through a fog that obscured their surroundings as completely as if a canvas had been drawn over the cockpits. Whirring dizzily through space, three thousand feet in the air, with your eyes closed! And ‘yet such a battle is daily life for the air mail pilots. The mail must be delivered. Schedules oT By TH. C. Nortu must be kept. The mail trains must be beaten. The very existence of the air mail depends on speed. Even the ele- ments must be conquered. Uncle Sam would countenance no fair weather fliers. It is between Hadley Field, New Brunswick, New Jersey, whence the New York air mail is shipped, and Cleveland, Ohio, that the battle has raged the hottest. And that hazardous route, beset by fogs, has been the field of the greatest victory. Planes Have Headlights, Too For night flying the mail planes are fitted with 250,000 candlepower headlights to insure safe landing. Here a mechanic is adjusting a head- light on one of the wings prior toleaving the field A typical scene during the loading of a night mail plane at the flying field. The bags of mail are rushed by truck from the city post office and transferred at the field into the body of the plane ey Can Fly with Their EYES SHUT! Thrilling Escapes of Pony Express Riders of the Air Forced to fly on schedule time, regardless of adverse weather conditions, the Hadley Field pilots have all but perfected the science of “flying blind’’; that is, navigat- ing a plane by the use of instruments when not a single guide is visible outside the ship. After months of practice and experiment, they are now able to fly for miles, with nothing but the instruments to direct their flight, without straying seriously from the course. In carrying the mail the night of the Dempsey-Tunney bout, Captain Chandler flew _ blind through the fog for an hour and fifty minutes. He hit a “low curtain” four minutes out of New Brunswick, and the first earthly ... ication he had of his whereabouts w»s when he came out of the fog and saw the lights of Bloomsburg, Pa. For nearly two hours he had kept to his sky route, solely by expert use of his navigational instruments. The near perfection of blind flying has been attained by the Hadley Field pilots only through trial and failure. It has simply been a case of master the fog-or give up the route. They have learned, through strenuous experience, to fly with- out visibility, because they had to. — | Eight pilots fly from Hadley Field to Cleveland, .and their adventures, the mention of which they dismiss with.& shrug, are more thrilling than ever were the Pony Express and the. Western. mail coach. In-summer they must tilt with fog and thunderstorms; in the fall with still denser fog and more severe rain-

Page 15

December, 1926 storms; in winter with _bliz- POPULAR SCIENCE MONTHLY ? 21 d the accumulation of ting the propeller, struts, fabric and wires of the airplane; and again in the spring with fog and snowstorms. Always there is engine trouble to con- tend with. Every season bears fresh enemies, and every day challenges the pilot to a new combat. And yet the mail is delivered and the schedules kept. The night of the inaugura- tion of the air mail service be- tween New York and Cleve- land is the one that Dean Smith remembers most clearly. Large crowds had ‘gathered to see the mail loaded, and to watch it take flight on the wings of the huge plane. MITH hopped into his wait- ing plane and was soon i viewed the wrecked plane lying on its back. As “Do you always land like that?” he asked drily. ‘ Smith got the mail from the ship alone, and communicated with an emergency field. A new plane was sent him, and he continued his flight. As he neared Cleveland, he ran out of gas and had to make another forced landing, this time with- out mishap. The mail was taken by truck to Cleveland, whence it continued its jour- ney westward. os apparently does not consider this experience especially exciting. Hooking one wing into the ground at sixty miles an hour, and ending up beneath the wreckage of an overturned plane, he assumes to be a reasonably safe way of rapidly disappearing westward. Watchung Mour:tains—Cush- atuck Mountain—Musconet- cong Mountain—the Delaware and lights that indicated Easton; in Pennsylvania now, and going in what seemed record time: Morgan Hill— Lehigh river—Kittatiny Ridge —Tamaqua; the motor hummed steadily on; Mauch Chunk Mountains—Broad Mountains—Catawisa Mountain—lights of Sunbury—Susquehanna river—Winkle- bleck Mountain—Niiany Mountain— headlights of an auto gleamed on the road below—now a few scattered lights of Bellefonte, for it was getting toward morning. Next would come a beacon, then another beacon, and then a weather reporting station. HAT actually came instead, was a faint chug from the motor and silence save for the rush of air past the plane. The engine had gone dead! Smith was about five hundred feet up. He used about two hundred of the dis- tance trying to get the motor running, but it was useless. He dropped a flare and searched the surrounding country. He saw only woods and hills. Then he spied a small, smooth field. But at the end of it were a house and barns. Rather cramped quarters for a landing, but the only possible one. Airway Lighthouse A series of beacons like this marks the route at night. Four searchlights mounted on a turntable tower fifty feet high re- voive six times a minute This odd “wind cone” nated from above. five-million candlepower As he headed downward at sixty miles an hour he knew he would crash the house, unless he “cracked up.” The plane plunged madly. Ahead was the house. Slightly to the right were the barns. A few seconds more and he would be upon them. With the ship under perfect control, Smith swung sharply to the left as he neared the ground. The left wing hooked into the earth and crumbled under. The plane pivoted about it in a huge semicircle, stood on its nose, and crashed on its back but a few yards from the house. Smith climbed calmly and unhurt from the cockpit, and viewed the ruins of his plane. Then he approached the farm- house and knocked. There was no reply. The farmer had slept peacefully through the whole performance. Another knock and a kick brought an ungracious reply from within. And Sinith returned to his plane to start unloading his cargo. In a few minutes the farmer, sleepy and ill natured, came out and phlegmatically A huge portable searchlight marks out a path as bright as day to assure a safe landing. The light is mounted on a rubber-tired carriage The Airman’s Weather Vane atop the landing field hangar tells the pilots the direction of the wind. It is illumi- Notice also the revolving beacon which lights the fliers into port landing. It is his favorite method of avoiding a head-on collision. “We are always getting into tight places and getting out of them, and that’s all there is to it,” he told me. All of the pilots assume more or less the same attitude towarc their experiences. Constantly fac- ing danger, accident, and death, they con- sider it all a part of the day’s work, what they are paid for. “We have thrills, excitement, close calls—of course,” said one of the Hadley Field pilots, Captain H. A. Chandler. ‘But they are only incidental. That we reach Cleveland on time is the important thing.”’ He called attention to the prog- ress made in flying during the last year by citing two “incidents.” “Last year,” he recalled, “I started from New York with the mail for Cleve- land. When about thirty-five minutes out, [ hit a fog bank. At that time we had not developed the use of our instruments nearly to the point we have today. Foran hour and ten minutes I flew without the faintest conception of where I was headed, keeping to what I hoped was my course by sheer guesswork. Finally I came out of the curtain and sighted the lights of an unknown city. It might have been any city within an hour’s run from Hadley Field— (Continued on page 148)

Page 16

22 Harnessing 7hirty Million Horses POPULAR SCIENCE MONTHLY December, 199 Marvelous New Ways in W hich Superpower May Ease Our) © Labors and Cut Costs} xe the é By Manus McFappey i : sca ’ i the radium atom. As everyone knows “a . J radium atoms are given to exploding ; When they explode they give out power, \ A small fragment of radium will keep it. self warm continually by the heat that its “a atoms generate within its mass. The o amount of heat produced is many thou. mt sands of times as great as can be obtained a from the same weight of coal. pe ANY scientists believe that similar : vast amounts of power may be . stored up in other kinds of atoms and ight be go how, for th a might be got out, somehow, for the use of T A Future Link in a Great Power System This is a typical power and irrigation dam, one of the many which are being constructed throughout the country and will eventually serve as links in the superpower system. The huge structure of masonry shown here, the Exchequer Dam near Los Angeles, Calif., backs up the waters of the Merced river to cover more than a thousand acres. The dam is 330 feet high and measures 955 feet along its curving crest. The mighty turbines in the power house at its base develop a capacity of 36.500 horsepower GENERATION ago the word ““power”’ held little significance for the average man. Steam and electricity, to be sure, were commonplace, but they did not affect every individual personally. Today, however, almost every person in the nation is an engineer in some degree and uses power at every turn. If he doesn’t drive an automobile he has a radio, a vacuum cleaner, a power fan, an electri- cal flatiron, or any one of a dozen other necessities that depend on power for their usefulness. So great is the influence of power on our present life that, were it cut off suddenly, we would be helpless—in fact civilization would collapse. Just as the blowing out of a little electric light fuse throws a household into confusion, so would the cutting off of power throw the world back into the dark ages. So it is with uneasiness that we read statements of eminent engineers that two of our principal sources of power—coal and oil—are limited and will be exhausted before many more generations are passed. And then we hear promises of a new, cheap and inexhaustible power just around the corner. That power is to come from the atom. Not today nor tomorrow, per- haps, but it is to come surely. We have the word of science for that. In his annual address as president of the American Chemical Society in Philadelphia recently, Professor James F. Norris of the Massachusetts Institute of When we learn how to touch the button lines and large units of production are vehicles and devices that make economical man. This project has been discussed ‘ actively at every power conference in . recent years, and Professor Norris now “ offers hopes of its success. But there is Meee co, scant possibility this will come in our pc generation. ; ; gl} In the meantime engineers are making ti rapid progress in utilizing the power we is have at hand through the development of . superpower systems. The newly coined p term “superpower” has been loosely used, 4 even in engineering circles. Shorn of all f its mystery, however, it means simply the d coordinated production of electric power. t This is being brought about by intercon- : Technology predicted a remaking of the necting individual power plants, both entire social order through the mastery of steam and hydro. f the atom by science. This progress is largely due to the per- ; “We know the atoms consist of un- fection of higher voltage transmission and thinkable amounts of bound up energy.” to mechanical improvements in generat- he said. “‘ They are like a jack-in-the-box. ing power. Interconnection, high-voltage ‘ the energy will spring out and we can use 4 And science will learn how to touch the button. In fact it has already harnessed production possible. They are the physi- cal structures that form a great power reservoir. SEATTL E POWER AND IRRIGATION, PORTLAND COLUMBIA RIVER BASIN (2,500,000 HORSEPOWER) SACRAMENTO AND SAN JOAQUIN VALLEY PROJECTS~ POWER AND IRRIGATION LOS ANGELES POWER AND IRRIGATION DAMS ON COLORADO RIVER (6,000,000 HORSEPOWER) MISSISSIPPL WATERWAYS SYSTEM WITH DIRECT CHICAGO- NEW ORLEANS AND PITTSBURGH- KANSAS CITY ROUTES (9000 MILES) BUFFALO -NEW YORK CANAL TO PERMIT FOREIGN-BOUND OCEAN LINERS TO SAIL FROM GREAT hs, LAKES PORTS BUFFALO NEW YORK PITTSBURGH & ~~ a , ae SHVILLE ATLANTIC USCLE SHOALS NAVIGATION, SEABOARD AND POWER PROJECTS ' WATERWAY CHICAGO KANSAS CITY ON CUMBERLAND AND . a TENNESSEE RIVERS IMPROVEMENTS (3,000,000 HORSEPOWER) RW W ORLEANS This map shows the projected or intended power and waterways projects in the United States. Engineers hope eventually to link the entire nation in a network of economical power supply

Page 17

1926 S sts ows, ling, wer, p it at its The hou- lined nilar y be and Se of issed ein now Te is our king T we nt of ined used, of all y the wer, rcon- both ‘per- 1 and erat- ltage | are nical hysi- ower December, 1926 With improved trans- POPULAR SCIENCE MONTHLY 23 «ion we call how under- abe development of the cheaper sources of wer from distant waters, such as the St. Lawrence river and other streams re- moved from the great centers of population. Al- so we can look to larger steam plants situated in the coal fields, thus doing away with the expensive hauling of fuel for widely scattered power producing units. HILE the saving on freight would be considerable, there are other economies — that would tend to cut deeply into thé cost of power were interconnection gen- eral. For instance, isolat- ed manufacturing plants at present are operating on an average of twenty percent of their capacity. They must have large capacity to furnish the needed power during “peak” hours and conse- quently they are working most of the time on “short shift.” With interconnec- tion, it has been deter- mined, they would be working at all times at full capacity. Money invested in equipment would earn five times as much as it So far the most impor- tant superpower systems have been built up in areas where water power is abundant, but there are equal possibilities for econ- omy in territories where steam plants are necessary. Whether our new power comes from steam or hydro plants, or even from atoms, does not concern most of us so much as the question of how we can get cheap power and lots of it. ODAY power is pro- duced at tremendous expense and labor. You pay your share of this ex- pense every time you make a purchase. Your clothes, your food, your automo- bile, even your amuse- ments depend on power for their production. The cost of mining coal and pump- ing oil are included, in some degree, in every- thing you buy. With cheap power avail- able to everyone, and a practical means of trans- mitting it at low cost per- fected, the production of all the common necessities of life could be increased enormously, and their cost reduced correspondingly. Take, for instance, the item of leather in shoes. does now. In addition, there is the possibility of using our water powers to greater advantage. The flow of water is seasonable and the power produced varies greatly. In flood limes excess power from the hydro plants could be turned into cen- tral reservoirs and steam plants could be shut down until needed again in low-water periods. The saving in coal alone would be tremendous. Another effect of superpower would be to distribute the power load evenly at all hours. For instance, New England and New York power plants could send most of the day load to the industrial centers and most of the nightload to metropolitan centers such as New York City, Boston, and other large users of night current. The result would be that, with all plants working full capacity at all hours, power would be plentiful and consequently cheaper. T PRESENT there are approximately 6,000 separate power and lighting systems in the United States. To make for the greatest economy, we need inter- connection of these isolated systems over large geographical areas, so as to provide great reservoirs into which larger streams of power may be poured from steam plants and our larger water powers. The connection of all the plants in the country in one giant system is not possi- ble at present due to the limitation of our present-day methods of transmitting power. Power can be carried by wires up drive a series of turbines. distributing wires. How Water Power Is Converted into Electricity Water at the head of the falls, surging into the spillway of the power plant, courses through an intake and plunges down great pipes, or penstocks, to These, through tall shafts, are connected with ‘electric generators at the surface, whose power is sent on its way through The great Niagara Falls power plants are of this type to 300 miles without wasteful leakage, but that is the limit so far. It can easily be seen, then, that even the great energy of Niagara Falls must be utilized at present within a comparatively restricted terri- tory. Science, however, is lengthening our transmission lines day by day and engineers are confident they will have channels for distributing their power as fast as they are able to develop and con- nect producing units. HE benefits of superpower already are being illustrated in the systems of large operating companies in several parts of the country. An excellent example is the “superutilities” of California. One California company represents the merger of about 125 units which once operated independently. This system has an an- nual output of about two billion kilowatt hours, two thirds of which is produced by water power at a great saving of coal. Similar conditions are found in all of the Rocky Mountain and Pacific coast states, where gigantic superpower systems are being developed. In the Southeastern states, too, a vast network of superpower transmission lines is spreading out. It reaches from Alabama to North Carolina. New England, also, is making progress in this direction. This, as you know, is made from the hides of horses and cows, The ani- mals are raised in the rural districts and their num- bers depend on the amount of grazing land available. Such land is limited, even in the Western states where the largest herds roam. But in the desert wastes of this country there is enough room to raise a hundred times as many cattle as we are now producing. It can’t be done now because there is no grass in these deserts. \ ITH cheap power, though, water could be pumped to the deserts and they could be turned into garden spots. Already this has been done in the Im- perial Valley of California, where the waters of the Colorado river have made a desert the most productive garden in the world. In the Imperial Valley it was a simple matter to tap the Colorado and distribute its life giving water over the arid soil. It is not so simple a matter to water all our other waste places. It is feasible from an engineering point of view, but the expense of pumping water to high ele- vations and for long distances makes it commercially impractical. In other words, it would cost more at present to irrigate the soil than the land and its products would bring in the market. Eliminating the high cost of power, however, every square foot of dry land in the country could be irrigated at a tre- mendous profit. (Continued on page 150)

Page 18

24 Folding Plane for Submarines The World’s First Under-Sea Flying Machine Designed for U.S. Navy Patrol By Epwin Ketcuum , YHEN Uncle Sam’s submarine S-1 emerged from beneath the waters of Long Island Sound near New London, Conn., a few weeks ago, it was seen to carry a strange burden on its back. The burden was in the form of a long cylindrical tank resting on the sub- marine’s deck just aft of the conning tower. The rear end of the cylinder opened, and from it, like a moth hatching from a cocoon, there appeared the body of a baby flying machine, a sea- plane. At first it was wingless and tailless. There was no pro- peller at its nose, and no land- ing gear beneath. But quickly these, too, came out of the co- coon, and quickly they were fastened to the body. Now a sturdy little single-seater rested neatly on its pontoons on the deck of the submarine, ready for flight. HE submarine submerged until its deck sank beneath the water’s surface. casting the seaplane afloat. With sixty horsepower motor roaring mer- rily and propeller awhirl, the little winged craft darted away, skimming the tops of the waves, then climbing into the sky. So, successfully, was com- pleted the first. test of the POPULAR SCIENCE MONTHLY United States Navy’s newest idea in fighting equipment—the submarine sea- plane, designed to add aerial “eyes” to the ships that scout beneath the sea. This remarkable midget plane that can travel under water was designed under the supervision of the Bureau of Aero- nautics. Weighing only 1,000 pounds, it can be taken out of its shell and assembled in nine Above: The tiny new submarine airplane assem- bled on the deck of the submarine S-1, prepara- tory to the launching, which is pictured at the left December, 192% How the Plane Takes-Off minutes, ready for the take-off. At top speed it travels at 103 miles an hour. Returning to the submarine after its flight, it floats back to the deck. Wings, propeller, landing gear and tail section are dismantled, and all are tucked snugly away again in the waterproof tank, ready for the journey under sea. HE idea of launching scouting air- planes from the decks of warships is not new; all the great navies have adopted the practice with varying degrees. of success. This, however, is the first time it has ever been applied successfully to under-water craft. Navy officials de- clare that it will give the submarine an effective patrol range far greater than ever was possible before. ; The proud pilot of this wonderful little water bird is the first sub- marine airplane pilot in the world, Lieut. Adolph C. Allen, U.S.N. Ready for the Dive The body of the plane and its dismantled wings, landing gear, tail section and propeller, are tucked in a waterproof tank Co a 3

Page 19

“8 ub- the len, An Ocean Heavyweight This Grouper, or Jewfish, weighing 200 pounds, is one of the biggest and ugliest of all finned creatures. Its mouth is big enough for an aquarium is the sea. That sounds paradoxical, but in the dark, unexplored depths are more mar- vels yet unknown than are on land. When every other field of nature is explored, there will still be new things on the bottom of the sea. The biggest deep-sea fishes, for instance, may be still unknown to science. They may be monsters. Thus far only small dredges have been used. No man can tell what strange creatures improved Gis tie « wonderland of all POPULAR SCIENCE MONTHLY 25 The New Wonders of the SEA Strange Fishes Climb Trees; Carry Searchlights and Saws By Ropert E. Marrix Glows in the Dark The Opisthoproctus is one of the oddest of luminous fishes. Notice how the light shines between the heavy scales of its armor—one of the marvels of the sea six inches long, and is shaped like a question mark, with a horselike head. When he dies we varnish him, mount him on a glass paper weight, and sell him at profit enough to keep the tank full of live specimens. dredging methods will bring forth. What is known now of the sea’s marvels only whets curiosity. . There are fishes with swords and saws, fishes with knives, with wings and with lights. There are great sharks and whales, as well as tiny animals of whom it takes forty million to fill a small net. Every scientist who goes hunting in the deep sea, if only 200 miles from the coast of the United States, brings back some new creature. The ocean teems with life. The field is vast, for the ocean covers three fourths the surface of the globe, and is hundreds of millions of years old. It covers an area of 139,000,000 square miles. Even its water is wonderful, for what we call the “‘salt seas” hold gold, copper and iron, sodium chlorate and other minerals. Their tides, strangely controlled by moon and sun, are a source of power yet unutilized. ; What are the greatest wonders of the Ask Dr. Charles H. Townsend, sea? Of Ancient Ancestry These mudfish burrow in mud along the shore. They are descended from one of the earliest forms of fish life, which existed ages ago Lighted Windows With rows of lighted ‘‘portholes’’ lining its wriggly sides, the Stylophthalmus winds like a lighted railway train through the inky blackness two miles and more beneath the ocean’s surface. Its eyes are at the ends of two long stalks sticking from its head like two lamps Director of the Aquarium in New York City, and you will hear some strange and interesting things, “What makes the public wonder most, and what is most wonderful, are not al- ways the same,” he will tell you. ‘‘ People who come to the Aquarium are most inter- ested in the little sea horse that climbs trees. He is among the few fishes with grasping tails. Like a monkey, he uses the tail to cling to seaweed and other marine objects. We have a little tree in his tank for him to climb on, and he likes it. This ‘hip- pocampus’ is only The Leopard of the Deep The eel-like body of the spotted moray is peppered with innu- merable dark spots ona whitish background. Its habitat is in the tropical Atlantic Ocean mt UR sightseers like little things and big things. After the sea horse, they like to look at the 200- pound Grouper, one of the biggest of fishes, called Jewfish in the books. They like to watch the shark swim- ming about with some ‘shark suck- ers’ fastened to his under side. These suckers attach themselves by air suction disks, like vacuum cleaners, on their heads. They are bluish fishes, shaped somewhat like the shark, though of course much smaller, and are ‘commensals,’ meaning that they eat with the shark. They take the scraps that fall from his table. The suction disks are among nature’s most remarkable appli- ances. “Probably, though, the greatest all- around wonder of the sea is the common eel. We have found out recently what a marvelous creature it is. Here is a fish that looks like a snake, attends'an annual League of Nations meeting in a certain spot in the Atlantic, can climb the Alps, does not have children until it gets old— and when it does, dies. ‘The life history of the eel, which has mystified men of science since Aristotle, has been solved only recently. The eel starts out as Leptocephalus, a larval form with gleaming eyes, thin as blotting paper and so transparent that you can read a newspaper through it. It is hatched from eggs laid in the Atlantic south of Bermuda. How the eggs get there is one of nature’s strangest, newest stories. “The newly born Leptocephali separate and form two great streams or currents, each swimming slowly to the home of its

Page 20

26 parents. The American Leptocephalus turns westward, and after a year, reaches the American coast. The European species turns eastward and takes two years to reach the streams whence the parents descended to the sea. Swimming upstream, against the current, they go as far inland as the borders of Switzerland. “The female eels go to the headwaters, males not above tidal waters. After the females have passed years inland, they decide the time has come to have a family. So, moved by this in- POPULAR SCIENCE MONTHLY his sword into whales, though he has been known, in desperation, to thrust through the bottom of a fisherman’s boat. He weighs 700 pounds. “Now, those are three wonderful crea- tures of the sea,” said Dr. Townsend. “But the wonders to scientific men who visit our Aquarium are somewhat differ- ent. The two creatures that arouse their greatest curiosity are the horseshoe crab, or Limulus, and the mudfish or bowfin, December, 19% and flourish. If scientists try to brin them up, they die before they even reach light and air, so that what we have to prove they exist are alcoholic specimens jn museums, models, paintings and photo. graphs. “There is the ‘Blind Ipnops’, for jp. stance. It has no eyes, but carries a searchlight on top of its head. Now, what does a blind fish want with a searchlight? Nobody knows, but perhaps the light attracts smaller fish when the stinct which may be coupled with a premonition of coming death, they start for the annual eels’ League of Nations meeting in the Sargasso Sea. In its warm waters, male and female eels from America and Europe meet. There is nothing quite like it in nature. When the two great streams of Leptocephali start for America and Europe as messen- gers from this meeting, the par- ents, having fulfilled their des- tiny, die.” UT to return to what the public likes—big things. Dr. Townsend thinks the public may not be so far off, after all, because three big creatures are certainly among the most won- derful things in the sea. They are our childhood friends, the whale, the shark, and the sword- fish. Consider the whale. Little more than seventy-five years ago he lighted the world, and built up a good slice of New England. At one time there were no fewer than 700 ships in the American whaling fleet. Until more re- cently, the whale sup- plied the whalebone for women’s corsets, and for the whips when they went buggy rid- ing. He supplied food and fertilizer. Is it strange that he is very scarce today, and that some kinds of whales are in danger of exter- mination? He is the largest animal of land or sea, sometimes sev- enty feet long, vastly heavier than the heaviest of elephants. lows. HE hammerhead shark has one of the most extraordinary formations among fishes. It has a flat head, with arms or wings—too broad to be called horns—ex- tending outward, with its eyes at the ends. It grows about fifteen feet long in tropical waters, and baby hammerheads a foot long have been caught off Sandy Hook. Dr. Townsend does not agree with William Beebe, the famous marine explorer, that sharks are harmless, and says he has many records of the killing of human beings, mostly in tropical seas. The swordfish really uses his sword—a pointed nose more than a yard long— mainly as a club to stun fishes. He darts among a school of small fry, and literally clubs them into submission. Familiar notions to the contrary, he does not ram A Curious Parasite How a “shark sucker” fastens itself to the under side of a shark’s body by suction disks. This strange fish feeds on scraps of food from the meals of its host An Under-Sea Toy Balloon One of the oddest of all fishes is the puffer, which, when taken from the water, blows itself up like a balloon with air it swal- The balloon collapses startlingly Sea Horses That Climb Trees The astonishing little sea horses are the known as Amia. The Aquarium donates many of these to European. scientists. The horseshoe crab, which looks like a flattened beehive with a rat tail, is the only living animal related to the extinct trilobite, whose fossils are so well known. The mudfish, which looks like many other fishes to laymen except for a thick- ening of the tail, is a descendant of one of the early forms of fish life. It belongs to a line long extinct, dating back unknown thousands of years. So you see the crab and the mudfish are, like some people, interesting chiefly because of their ancestry. “If you want to get a real thrill, go down deep into ‘the waters under the earth’ and see the strange creatures there. In that eternal darkness, miles down, under terrific pressure and intense cold, nature has evolved creatures that can live only fishes that climb trees. grasping tails, like monkeys, with which they cling to seaweed. They are shaped like question marks, with horselike heads Ipnops is hungry. It is brown in color, and of rather small size. “Some night someone who has been indulging in post-Volstead is going to dream about a Stylo. phthalmus, and then swear off. The Stylophthalmus is a silver colored, wriggly, eel-like fish with two long stalks sticking out from his head, and eyes at the ends of the stalks. Also, he has a string of lights along either side that makes him look like a subway train. “TF YOU goswimmingand get in- to too deep water, the Gastro. stomus will get you if you don’t watch out. His mouth is bigger than his body and in fact, mouth, stomach and intestines seem to he all one. He may not see you, though, for his eves are no bigger than pinheads and are lo- cated on the tip of his upper jaw.” Many deep-sea fish are lumines. cent—“lit up” in one way or another, to il- luminate the surround- ing gloom. There is the lantern fish, about the inches long, iridescent copper above and sil- very white below, yet with nearly a hundred lights. These are made by small, round lumi- nous organs divided in some species into three general sets, thirty-two oneach side of the body, twelve arranged irregu- larly along head and body, and from four to eight above or below the base of the tail. The lantern fish can turn them on or off as he wishes. They lure small fishes, and help him escape his enemy, the Astro- nesthes ‘‘eater of stars,” whose favorite meal is a well lighted lantern fish. They have HE Beebe expedition on the Arcturus got from the depths some new varie- ties of lantern-bearing Sea Devils, hideous- looking black fishes with lights at the end of stalks or tentacles growing from their heads. These creatures are little more than eating machines, with enormous teeth outlined with luminescence. In some species, the mouth is four fifths of the body. Female deep-sea fishes have been found with tiny adult male fishes growing from the side or head or behind the gills. These parasitic males get all their nourish- (Continued on page 151) size of a minnow, two. Decet was! was Fac repr gooc be u cars alre: and bile imp met and inte scr gro sea For jun eve me ves ust is th int su

Page 21

19% ring ach to ito. in- December, 1926 POPULAR SCIENCE MONTHLY 27 Amazing Ways We Use WASTE New Discoveries Feed Us, Clothe, House and Transport Us with Materials Once Constdered Junk By Lee Carter HEN Henry Ford purchased 199 W steel merchant ships from the United States Government he wasn’t actuated by altruistic motives. It was merely a question of money value. Each one of these apparently useless ships represented just so many tons of perfectly good raw material that could be used in the manufacture of cars. Thirty-five of these ships already have been torn down and made over into automo- biles, tractors, machines and implements. The steel and metals went into auto engines and chassis; the lumber in booms and spars was turned into wheels and auto bodies; scrap wood and cork were ground for packing purposes; searchlights were sent to light Ford aviation fields; deck lumber was made into crates and boxes; even nails were melted down and the metal used again. Every scrap of the vessels torn down so far has found some use in the Ford organization. ND Henry Ford’s salvaging of the ma- terial in these otherwise useless ships is but one phase of the enormous effort that is now being made in every line of industry to eke out our rapidly dwindling supply of virgin materials. The World War, of necessity, did much to bring this new science of salvaging waste into practice. Since then there have come, one after another, remarkable discoveries of new ways to feed us, clothe us, house us, transport us and keep us comfortable with materials that once were considered junk. Weeds, cornstalks, old shoes, rags, the scraps from our tables, rusted and broken-down machines, the garbage and sewage of cities, broken boxes and barrels—these and many other Below, piles of discarded magazines which will be converted into new paper and eventually become new magazines again, at a large plant situated near Antioch, California items of “trash,”’ science has found, can be salvaged, saving millions of dollars a year. Yet even with this new knowledge the amount of waste in the modern world is appalling. An outstanding example is in fuel, particularly automobile fuel. Twenty-odd million cars in America are burning up fuel with profligate disregard of the future. Nor is that all. In burning this fuel, even in the most efficient motor cars, there is a tremendous waste of energy. At least one third of the theoretical power of the fuel is wasted in the exhaust; another third in the radiator; still more in fric- tion; so that in the end only a small fraction is put to work in propelling the car. Engineers are seeking to develop machinery that will salvage this energy. Meanwhile, by improved processes of petroleum refining, they are extracting useful by-products ordinarily wasted in gasoline combustion. For example, a cer- Courtesy Iron Age (Above) A new magnetic ma- chine for separating high-value monel turnings from the lower- value turnings of iron and steel at the General Electric Company. The process saves $20,000 annually in scrap tain gummy residue which clogs gasoline motors can be recov- ered and used for making artificial rub- ber. The possibilities for such salvage work have barely been touched. In coal consumption the waste has been equally extravagant. Of every ton of coal you burn in your furnace, at least three fourths is lost up the chimney. But here the work of salvage has progressed farther. ASES given off by burning coal are being used to increase the growth of plants. From coal tar hundreds of valu- able products are being produced, while the waste products of coke ovens are responsi- ble for the prosperous American dye indus- try. And only the other day chemists announced the success of a new fuel from coal which will be smokeless and almost without waste. It is called “semi-coke.” Besides being smokeless, it is said to burnas easily as coal and much more easily than coke. In its production by alow-tempera- ture process, gases, oils and ammonia ordi- narily lost when coal (Continued on page 153) Reconditioning old ropes at a plant on Staten Island, N. Y. The material will then be shipped abroad to be made into cheap carpets, twine, and similar products. This is one phase of the effort being made in industry to save waste in our dwindling supply of raw materials

Page 22

The Battle for the Championship Dempsey, in the foreground, is weaving in with his characteristic crouch, while Tunney waits his oppor- to tunity. Note the look of determinaticn on Tunney’s face HEN Jack Dempsey, black- browed, scowling, aflame with his innate delight in battle, leaped from his corner in the Sesqui- centennial stadium on that memorable evening last fall, it was with the confident belief that he was about to begin another of those short, vicious slaughters that had marked his seven-year reign as world’s heavyweight champion. A few seconds later, Dempsey, the “killer,” the “unbeatable,” had lost his championship. ‘True, it required ten rounds of fighting—a half hour—before the title officially changed hands. But actually the championship had passed within a half minute after the fight began. It passed with the delivery of the most amazing blow ever known in the prize ring by the most remarkable young man who ever stepped into the “squared circle.” The blow was a straight right-hand punch that was aimed at Dempsey’s jaw, but which actually landed high on his left cheek. I call it the most amazing blow for several reasons. First, it won the heavyweight championship for a man to whom not one person in a hundred conceded a chance. Then, it won the title without a knockout. But the most astonishing thing about it was this: Although its actual delivery required only an infinitesimal part of a second, it really started for the rugged and desper- ate face of Jack Dempsey about fourteen months before. For that I have the word of the man POPULAR SCIENCE MONTHLY who conceived and executed the punch—Gene Tunney, the new heavyweight champion. Tunney told me the amazing story of that blow on our way from New York to Philadel- phia a week or so after the fight. I had informed him that the editor of PopuLar ScrENCE Montuiy had asked me to obtain from him his own ver- sion of the battle with Demp- sey. : F COURSE; gladly,” ‘smiled Tunney. “I’ve had a warm spot in my heart for PopuLar ScreENcE Montu- Ly for a long time. In June, 1925, PopuLar ScIENCE print- ed an article I wrote. I had called it ‘What I Have Learned about the Vulnerability of the Human Body,’- but the editor changed the title ‘The Blows That Made Me a Champion.’ I was American light heavyweight champion at the time, you remember; but, in the light of what has happened since, changing the title of my article was almost prophetic, don’t you think? And Jack Dempsey’s body,” he added with a sly. grin, “was just as vulnerable as that of anybody who happened to read my article. “Anyway, I can add another blow now to the list I described in that article. Let’s go back t6 the beginning. “For seven years, ever since the day Jack Demp- sey knocked out Jess Wil- lard at Toledo, I’d had the idea that some day I was going to be heavyweight champion of the world. Maybe the idea wasn’t reasonable at first, for then I was only a light heavy- weight, a ‘long string bean’ of a youngster, just turned twenty-one. I had won the boxing championship of the A. E. F. in France, and I knew I was bound to grow heavier, stronger and more skilful with training and practice. Still, before the Toledo fight,. I couldn’t A Good Citizen December, 19% unney Tells How “I Practiced One Punch for More Than a Year,”’ Says New Heavyweight Champion—W hy He Knew He Could Not Fail Willard, who stood six feet, six, and weighed two hundred and fifty pounds or so. “Then Dempsey beat Willard. Demp. sey was nearer my own size. ‘I would have a chance with that fellow,’ I told myself. Some of my old buddies in the Marine Corps, who’d seen me fight in France, thought so too, so I started out after the championship in earnest. “T’ve always liked to think things out for myself—to plan ahead. In deciding to go after the heavyweight champion- ship, I knew that hit or miss methods wouldn’t get me far. So I concentrated on the problem and tried to list all its details in order. “T decided that my task of winning the title consisted of three things: Perfecting my physical resources for that particular job; studying the man I was to meet, to learn the vulnerable spot in his armor, and acquiring a mental mastery over myself so that I could go through with the job unexcitedly, without mistakes and false motions. “Kind of a large order, wasn’t it?” inquired Gene. “And don’t think [I didn’t know it. To begin with, I needed about twenty more pounds of fighting weight before I would be ready for Dempsey.” te. 7 ID you special methods for building up your body?” I inquired. “Nothing much— aside from sane outdoor exercise and plenty of sleep,” replied the cham- pion. “I had no bad habits, no leanings to- ward dissipation, so it was not difficult for me to live a regular, ordered life. But I cut out tea and coffee and drank milk only; also I made it a point to keep away from the city as much as possible. Although I was born and raised in the Greenwich Village section of New York City and love my old neighborhood, I am happiest and feel best when I’m off in the country, climbing the hills, use any’ quite visualize myself as an equal match for a giant like Tunney all dressed up—a good citizen as well as a good fighter. His methods teach us a lesson chopping wood, hiking and playing golf. “When I first fought Decemb A By as a writer terrib was | ticing somel I rea provi “ A abilit in 1 denc I kn wha’ ago, clait kne' bett box! but go |

Page 23

9% a a eS ae ee. Fe December, 1926 He Won the TITLE By Ep Van Every as a professional, you boxing writers thought I was pretty terrible. Probably I was, but I was keeping close tabs on myself, prac- ticing and training ceaselessly; I learned something new each time I fought and [ realized that I was going ahead—im- proving—all the time. “ 4ND as I improved in. skill, -in strength, in speed, in punching ability, in ring generalship, my confidence in myself - increased apace. This confi- dence was founded on facts and logic. I knew what I could do, and I knew what I could not do. Three or four years ago, for example, I would not have claimed that I could beat Dempsey. I knew then that I was a hundred percent better fighter than I had been when I was boxing in Army tournaments in France, but I knew, too, that I had a long way to go before I was ready for the ‘big shot.’ “T knew three vears ago, however, that I was big enough for Dempsey, which, you'll recall, was one of the essential details of my plans for -winning the championship. I knew, too, that in physical condition, and ability to take punishment and recuperate, I was a match for any man in the world. My fight with Earry Greb in which he admin- istered to me my only defeat and took away the light heavyweight championship was enough to convince me of that. Greb gave me one of the worst beatings taken by a fighter in recent years. Yet he could not knock me out, or even knock me down. So badly did he punish me that I collapsed in my dressing room after I left the ring. Yet the thought in my mind when [ revived, and the one by- standers tell me I voiced when I came Keeping Cool on the Eve of Battle Tunney and Casey Jones, famous test pilot, landing at Philadelphia from Stroudsburg the evening of the championship fight. Over the protests of his friends, he made the trip—his first one—in a plane The Punch That Won POPULAR SCIENCE MONTHLY This is the right-hand punch which Tunney practiced in- cessantly and which really decided the championship in the first round. Although its actual delivery required only an infinitesimal part of a second, it really started for the rugged face of Jack Dempsey fourteen months before the actual combat to was, ‘He couldn’t knock me out! I can lick him!’ “Having the size, then, and the stamina, my next steps were the study of my opponent’s weaknesses and the acquisition of a knockout punch. Some- how there always seemed to be prevalent an opinion that I was not much of a puncher. Just why I never could see. I had knocked out men who had met the best of them without taking the count. There were, for example, Bartley Madden and Tom Gibbons. Even when I knocked out Gibbons, whom Dempsey himself couldn’t put away, the general opinion of fight experts seemed still to be, ‘Oh, yes, Gene Tunney is a clever boxer and pretty fast for a big fellow—but he can’t hit!” ‘T THOUGH, basing my _ opinion , only on facts and logic, knew I had punch enough for Jack Dempsey, or any other man. What, though, was the weak spot in Dempsey’s armor? Where was I to land my punch to be most effective if I got the chance to meet Jack for the championship? “T had been studying Dempsey’s ring methods. Invari- ably he rushed out and whaled away until some- thing dropped. Against slow- moving big fellows like Willard and Firpo that system of fighting was mighty effective. Againsta shifty boxer, though, who wouldn't per- mit the champion to reach him with his deadly: punches, the system didn’t work so well. The late Bill Brennan, who was no great shakes as a boxer, stood off the cham- pion for twelve rounds before Dempsey scored a knockout. Tom Gibbons lasted through a fifteen-round fight with him. Twenty-seven rounds of fighting and the ‘deadly’ punch of Jack Dempsey only landed once! Why? Because, obviously, Dempsey was not the superman that many people believed him to be. Fight him his way, and you were gone. Make him fight you your way, though, and he was no more dan- gerous than the rank and file of heavy- weight boxers. That was my cue—and I took it. “T discovered, for example, that Dempsey could be turned around very easily—probably because he rushes for- ward on his toes. It was well known that his most dangerous punch was a left hook. When I was training for the Dempsey fight at Stroudsburg, Pa., many people remarked how often my sparring partners reached me with their blows. ‘If that’s the best Tunney can do against second- rate boxers, they’d say, ‘what will happen to him when Dempsey lands on him?’ In fact, some of my sparring part- ners had the same idea. Only two men in my training camp believed I[ could beat Dempsey. Well, all I can say is that nobody saw any of my sparring partners reaching me with left hooks! That was Dempsey’s blow; that was the punch I was training to avoid. e OW, I knew that Dempsey, when we met, would do his utmost to knock me out in a punch. He was im- mensely proud of his murderous wallop. And fourteen months ago the thought occurred to me that the best possible way of treating Jack to a surprise would be by reversing the process—by my knocking him out in a punch.” “What’s that?” I exclaimed. “Do you mean to say you actually counted on winning from Dempsey with your first punch?” “T did,” said Gene positively. “ Demp- sey was accustomed to seeing his oppo- nents back away as he rushed them. I figured that by meeting his rush with a rush, and putting all I had into a single punch, I could knock him out with the first blow of (Continued on page 155)

Page 24

POPULAR SCIENCE MONTHLY How Many /Vords Do YOU Knowr Lawyers Use about 23,000, Mechanics 5,000 — Here’s a Test for Yourself about a million words to choose from to express any idea that may enter your head. Out of that million you must draw the words to conduct your business, pass the time of day with your neighbors, or write your love letters. No one man knows all of the English vocabulary. The average man uses only a few thousand-words. An intelligent artisan has a vocabulary of 5,000. A person of education knows from 8,000 to 10,000 words. A greater vocabulary than that is unquestionable evidence of superior Ye have, in the English language, check up has been devised by Frank Horace Vizetelly, managing editor of the New Standard Dictionary and dean of American lexicographers. He has pre- pared lists of words so selected that, for example, familiarity with all the 100 words in List A indicates a vocabulary of 6,000 words. It is not necessary to define each word exactly; a “speaking acquaint- ance” with it is sufficient. If, instead of 100, you know ninety-five of them, or any other number, multiplying by 60 will give your vocabulary. Similarly, List B, with a 100 per- The man with the biggest vocabulary inthe world—Dr, Frank H. Vizetelly, noted lexi- cographer and managing editor of the New Standard Dictionary, who devised this test education. To test your vocabulary and find out how you rate, a way that affords a quick cent score, shows that you have a vocabulary of 12,000 words; List C, a vocabulary of 25,000. List A. For each of the words below, you prob- List B. If you know all of the 100 words ably know 60 others. Therefore, 1f you know below, your vocabulary is about 12,000. Mul- the entire 100; your vocabulary is about 6,000. tiply each one you know by 120. abate dale jubilant scathe administrator epicure mace scrunch affirm dearth latter seminal alloy erysipelas moiety sever ample denote ligament shallow antipathy excommunicate monsoon siphon appal deter manifold sheer aquiline expatiate neb slabber balk diction marrow shorn arraign extenuate ordain slink bask discrepancy misprint skeptic automaton festoon pagan snigger benefaction draper muff smart babble fizz parable somnambulism bolt engross mussel source bedlam fluctuate peal spawn brig evasion nib statuary beeve fulminate perception stamen browbeat facsimile ode stream blowze gabble pictorial steppe burnish feign onset stud bounden goiter pip stipulate caprice filter oversight sublime brandish hackney pliant sunder cherish foreland postpone succumb carnivorous handspike postern swain chock forte preamble talc caw hilarious primeval tabernacle clink frail prejudice tenuity cervine huckster quadrant tolerable coincide gangway preside texture clandestine inadequate quartern transcend commune glazier profess tidal colter inflate ramrod trinal composure gram protrude tinct congregate invoke rational turquoise consign gravity radical topple covet kink residual vellum contention grope recommence trawl deign languid retaliate volatile converge gullet refuge unassuming dissonant leaven rife waft cosmos horde repress undergrowth divulge leonine roseate wary crevasse identical revile unfurl duress liquidate rudiment wilt crotch inkling roan uppish ebon longevity sanctum yew cue inter saber whisk egress lucid saunter zodiac List C. An exceptional vocabulary—25,000 words—is indicated by familiarity with all of the 100 rather uncommon words below. Multiply each word by 250. abstemious ciliary eloquence incursion millennium plantigrade sillabub torose ague condone emporium induct mote poise sodality toxin amain cordate farrier insoluble nape polypus spicular tret anneal craniology folderol intestate nomad portend spittle trow assiduous curvilineal frieze kail nostrum pugnacious springe tyro ~ barouche declivity genealogical labial obloquy purge staminody unmoor bibulous derogate gibe loam ostracize quintessence __ storied valetudinarian bissextile direful heptagon malapropos palmiped redundant suppliant vertex blear disparage hoiden matrix paroxysm remuneration swob vortex bole dory hydrology medallion penance replevin syncopation voracious candid drachma imbroglio meniscus permutation sediment temporal weazen catalepsy dross imperturbable metric pestiferous septuple tessellate xiphoid chapfallen incog phosphor thill Qn. ee ae ee

Page 25

pecember, 1926 POPULAR SCIENCE MONTHLY 31 [Is Your House Heated Properly? How Radzators Should Be Placed, Piping and Connections Planned, : and Radiation Estimated By Joun R. McManon «yg VOU’RE a fine pair.” I informed Rob and Ellen, “to leave the heating question to the last mo- ment, when you are about ready to move into your new home.” “Guess we didn’t believe winter was coming,” laughed Rob. “Besides we got tangled up in that three-cornered argu- ment about steam, hot water and hot air. “Does it really matter, the delay?” asked Ellen anxiously. “Tt is not deadly serious,” I assured her. “There are advantages in planning ahead for your heating system, and an early installed furnace gives the inciden- tal benefit of drying out new plaster and paint. But you're a lucky couple. The fact is, you are going to win by this de- lay.” “Prices going down, eh?” quoth Rob. “Better than that. A new scientific discovery that you can benefit by, not only saving your cash but adding to your comfort.” “Who is the scientist and what is his dope?” “He is Dr. Charles W. Brabbee, a European expert who is now doing heating research for a leading American corporation. He has a laboratory at Yonkers, N. Y., where he tames the flighty and elusive thermal units, prac- tically making them eat out of his hand. “The gist of his new idea is simply this: More heat at the floor and less at the ceil- ing. A knee-high radiator, says he, does more useful work than its waist-high fel- low of even larger size.” “I always thought that ceiling heat was not wasted; that it helps warm the next floor,”’ said Ellen. _ ANY people think so,” I replied, ‘“‘and the idea may be correct. But Dr. Brabbee assures us that ceiling heat in excess is wasted. The Egyptians and the Romans had the right idea in putting heat ducts through their floors, but we moderns have gone astray, he suggests, with our but in its heating effect at knee height —which the scientist claims to be the true test of practical efficiency—it sur- passed its big com- petitor by all of seventeen _ percent. Add up and you see that low placement will save you toward one third on your heating system.” ‘Knee height does not sound quite scientific,” murmured Ellen. “That is true—Dr. Brabbee’s dis- covery is not as exact as a chemical formula; yet it can be usefully applied. I would personally interpret it to have no radiator higher than twenty inches, or under-window size, except where a nar- row space compelled taller installation. You want a cool head and warm feet. You get both by keeping down the source of heat.” “TI guess the promoters of hot air systems will claim a boost from Brab- bee’s work,” suggested the young man. **No doubt, in so far as the floor regis- ter conforms with the general principle of a low source of heat. Of course the heating question involves other impor- tant factors,—distribution, uniformity of supply, ease of maintenance and longevity of the system.” _ OULD you advise hot air for our house?’’. asked Ellen. “Winter will advise and compel it as a hurry-up job, if you don’t look out,” was my answer. “The one-pipe kind can be installed in a day compared with a week or so for a steam or hot water system. “It is the least expensive of all outfits in first cost, say one hundred and twenty- five dollars put in. Steam is at least double, and hot water is still more ex- Radiators wherever possible should be knee-high. Low place- ment will save you almost one third on your heating system pensive. Of course prices are deceptive when we overlook size, quality and service. Hot air is fairly distributed from a central register in a square house, but not in an irregular or rectangular dwell- ing. An old method of spreading the heat with large pipes is unsatisfactory, since the pipes are cumbersome and perishable. Take the one-pipe kind or none.” “Is it true that the modern hot air furnace does not send smoke or gas into the house?” asked Rob. “TT IS relatively true. The inner sec- tions are sealed together with furnace putty, which tends to crack with excessive contraction and expansion of metal in fire contact, not water-jacketed as in steam or hot water boilers. Renewal of puttying every few seasons is necessary. ‘For soft coal a solid dome of cast iron makes a tighter, more lasting job, while sa steel dome serves with anthracite and, being larger, emits more heat. A firepot which has metal lugs or corrugations out- side will manifestly throw out more heat than a plain surface, and it will also minimize joint-breaking movements. Don’t buy a pig in a poke. Look over the furnace before it is covered with its gal- vanized iron jacket.” “I suppose an oil burner can be used with a hot air furnace?” “Yes, but pick out a burner that makes little noise, because x ; 7 WINDOW AREA OUTSIDE WALL AREA VOLUME OF ROOM RADIATOR i ° high radiators. We have been AREA an open register or pipes convey wrongly estimating heat in mere AA (so. FT.) sound easily. Any fuel from terms of radiator surface, dis- A AL wood to oil may be used in a hot regarding the vital factor of low — air furnace. You can also heat placement.” a water with a coil inside the fire- **Did the doctor test high and (lA pot.” low radiators together?’ asked Rob. “Yes, one thirty-eight inches high with another twenty inches high. The little fellow gave out eleven percent less heat on the old standard basis of calculation, Interpreted, this diagram means: divided by 3, plus the square feet of outside wall divided by 10, plus the cubic contents of the room divided by 200, equals the total radiation which is required forheating that room comfortably Ne) How to figure the radiator surface area required for one room. 200 Square feet of window area ‘Speaking of chimney draft, what are the rules for a good one?” pursued Rob. ‘*For a small house an eight by eight inch flue and a chimney height of at least twenty-five feet are required. The next flue

Page 26

32 size is eight by twelve inches with a minimum chimney height of thirty-five feet. The flue should be used only for the furnace, not shared by the cook stove. Make the smoke pipe en- trance air-tight with a mixture of asbestos and ce- ment, half and half, mois- tened to a putty. The chimney should project at least two feet above the highest point of the roof, no flue lining exposed above brickwork and no cap or cowl placed on chimney top. Many houses show violations of these prin- ciples, and you can bet they pay the penalty in poor draft and waste of fuel.” 5s OW can I check up on the heating con- POPULAR SCIENCE MONTHLY bee’s knee-high _ preferenn —our cited room wo; need a_ radiator length around five feet. Of Cours we may divide this length into two radiators, stra. tegically placed. A three. column radiator twenty- inches high will do aq) the same work with 4 length of forty inches, while tractor who says I need a certain size of steam boiler? Perhaps that boiler is too big, but how can I tell?” “That is not ahard one for anybody who can add, subtract and multiply. You have the right notion in wanting to verify the sayso of the con- tractor, for your own satisfaction. There are several rules for figuring the size of a heating system, all based on seventy degrees inside the house and zero out- side. They agree fairly in result. Here is a simple rule. Allow one square foot of radiation to 3 sq. ft. of glass, ditto to 10 sq. ft. exposed or outside wall, ditto to 200 cubic ft. of space. “For example, a room 12x15x10 ft., two sides exposed, with three windows, has glass surface totaling 45 sq. ft., which divided by 3 equals 15; also 225 sq. ft. of exposed wall, which divided by 10 equals 221% sq. ft.; also 1800 cu. ft. of space, which divided by 200 equals 9 sq. ft. Add 15, 22%, 9, and you have a total radiation required of 46 14 sq. ft.” *“We have to do that for each room, I suppose,” said Rob. “TYXACTLY. And you can figure it all from your house plans instead of laboriously tape-lining each room. Then add up the total, which amounts, let us say, to 300 sq. ft. But this means only the radiator load, and we must allow for the piping by twenty-five per- cent, which raises the figure to 375 sq. ft. “To this we must further add a safety margin to cover such items as extra cold weather, air leakage, poor fuel, bad firing, quick heating demands in the - morning, and the fuel-saving advantage of a furnace that is not pushed to the limit. The safety margin is seventy-five per- cent for a well built house. We thus double the figure for room total and arrive at a grand total of 600 sq. ft., which is the indicated size of our steam boiler. A table of boiler ratings issued by the manufacturer shows that the nearest to our indicated size is 625 sq. ft. That’s what we want.” “I see a chance for an argument with the contractor over that seventy-five per- cent margin,” observed the young man thoughtfully. “It would be better to consult a quire. Weather Bureau chart,” was my com- ment. “If you have little or no zero weather in your locality and figure on some auxiliary heating from a kitchen range and an open fireplace, you can pare down the margin a bit. But suppose that you decide later to heat the garage from the house, or you add a room, then you may regret figuring too closely on boiler size. With a correct layout, steam pressure runs from a few ounces to a maximum of two pounds in very cold weather. A size too small means extra stoking work, more pressure, less effi- ciency.” . OES that rule on boilers tell any- thing about the radiators that should go with it?” asked Ellen. “It certainly does, about all you need to know except the new discovery of Dr. Brabbee. The radiation for each room gives the radiator size. Take the room in the example that needs 46% sq. ft. We can look over a manufacturer’s table and find what we want in almost any height, length and width. Radiators are made in sections of one coil each, so they can be as short or as long as you please. They are also made in one, two, three and four column widths. Naturally it increases capacity to multiply col- umns, and by the same token more width-space is required at the wall. “If we use a two-column radiator twen- ty inches high—which meets Dr. Brab- Are You Planning to Build? R. McMAHON'S services and those of the Popular Science Institute of Standards are available to assist our readers in solving their building problems. Letters will be answered free of charge. Write to the Home Service Department, PorpuLar Science Montaty, 250 Fourth Av- enue, New York City. A Comparison of Systems The “big three”’ of heating in- stallations, and what they re- Hot water has greater long-run economy; warm air and steam cost less to install a four-column of similar height has to be only three feet long. We can’t always exactly match our theo. retical need with size and style of radiators as many. factured, but we come as close to it as possible.” ‘T WOULD like one of those low sizes under g window seat in the living room,” said the young mistress of the home. “Then you will have to add thirty percent to its capacity to allow for de. creased radiation value. The same applies to any radiator enclosed by a screen or grill instead of being placed in the open.” “What is the correct location of ra- diators?”’ asked Rob. “Between windows, sometimes under them, along a first floor staircase—al- ways along outside walls rather than inside walls. In a room with two ex- | posed sides, put the radiator in the far exposed end. The north side of a house usually needs more heat than the other sides. Never tuck a radiator behind an inside door. If in time you discover that there is a mistake in radiator distribution, you can correct it by taking away a few sections here and adding a few sections there. While you can thus readjust without regard to boiler capacity, you can increase the total radiation only provided the boiler has a good sized margin of power.” “7 HAVE heard about the vapor sys- tem,” said Ellen. “‘ What is it?” “*TIt is a choice variety of steam outfit. Owing to a partial vacuum in pipes and radiators, obtained by chimney draft or otherwise, the slightest amount of hot vapor in the boiler speeds through the system. Thus it heats rapidly, without pressure of more than a few ounces, and is noiseless—without any pipe thumps or valve sizzles. “Being more elaborate, having more pipes and a radiator surface perhaps twenty percent greater, the vapor sys- tem is bound to be more expensive. Why the greater radiator surface? Because vapor or boiling-point steam has a tem- perature of only two hundred and twelve degrees, but its temperature rises about three degrees for each pound of pressure up to a certain point. At three pounds pressure, steam is ten degrees hotter than at the boiling point.” “Does the ordinary steam plant need more than one pipe leading to each radiator?’ asked Rob. “No. For the average home the two- pipe scheme is in the discard along with the overhead or down-feed method. There may be a (Continued on page 157)

Page 27

far ise ler an lat on, ew ns it. id or ot he ut id 08

December, 1926 POPULAR SCIENCE MONTHLY 33 You Can Do These Tricks Strange Effects You Can Produce to Mystify Your Friends By Kennetu B. Murray AGIC tricks are a never-ending LV source of interest and fun, though their successful performance requires skill and patient ne hese six are unusually effective. Try them!

Where Did It Go? — is a mystifying trick that can be per- formed at no cost and with little prepara- tion. In view of the spectators you place a half dollar in the palm of your left hand and squeeze it with your right hand until it apparently has been squeezed into nothingness and disappears. The secret, as revealed above, lies in a little round disk of flesh-colored cardboard attached to-a piece of elastic which runs up the sleeve, where it is secured with a safety pin. The disk

The Floating Hat you can make an apparently quite normal straw hat cling to your hand and float through the air, then suddenly drop to the floor, to be picked up by the spectators and vainly examined for an explanation. A flesh-colored silk thread does the trick. It is tied around the hat at the middle, allowing barely sufficient slack to place the hand under, as shown in the illustration below. To cause it to drop, break the thread by doubling up your hand. Conceal thread while hat is examined

Water Changed to Wine OURING water out of a milk bottle into glasses, the water either changing to wine or remaining water, as you wish, is a mystifying performance easily learned. Prepare beforehand pastes made up of aniline dyes, in the proper colors, water and a dash of liquid glue. Place specks of the paste at different positions on the mouth of the bottle, as shown above. Then,when the water is poured, you can make it carry any of the colors with it, or none

on one side is smeared with adhesive wax, so z : ey that the coin sticks to it and flies up your sleeve i at all, by holding the bottle in correct position PIN THROUGH WAND NEEDLE m—- LEAD WEIGH? STIFF WIRE Pes : THREAD SOLDERED WITH RING FOR FINGER The Bowing Cigar Making a Wand Rise PAPER CIGAR on a hat can be made to bow = ‘THE drawing at the right shows how a TUBE

wand can be made to rise in the hand << apparently of its own volition, as above. With thread around little finger, the paper- tube wand rises as the lead weight descends graciously to the company and even do a lively dance (above). Device used is at left. Your finger is thrust in the thimble, needle point shoved through hat, and cigar held on point

A Mind Reader’s Secret—This One Needs Practice written. Here’s how it isdone: Cuta slitin envelope (right-hand picture), and place paper in it. Spectator’s question, however, passes through slit into hand (center, above). Dummy question can be seen burning when match is held behind. Read question while spectators watch the burning , gaan any spectator to write a question, you place the question in an envelope without looking at it (left, above), seal it, and light it with amatch. Question can be seen, but not read, when match is held behind envelope while burning. Nevertheless you then announce what was

Page 28

34 Benjamin Franklin, Hxperimente ELOW, the odd sentry box ona high tower, suggested by Franklin to prove that an iron rod could avert lightning from a building. From thisidea came the lightning rod now universally used Franklin used tools, so in the busi- ness of life he used words. Wherever and however you take him, you will find him using language as a mason uses cement, as a bridge builder uses rivets or as a motorist uses an accelerator. In science he could describe an experi- ment even better than he could make one; with the result that men “talked” back to him from every quarter of the world, often sending him valuable data for his experiments. Words were things to work with, to accomplish some definite purpose. Think, for example, what his pen could do, after he had stood for a midnight hour beside his window, looking at a sky as rosy as if the dawn were already coming. Is it to be supposed that he could resist anything so fascinating as the Aurora Borealis or, as they call it in the southern hemisphere, Aurora Australis? The. scientific study he gave to this phenomenon absorbed him. He watched the arch, or corona, appear in the north- ern sky, with its highest point just about over the earth’s north magnetic pole. Then he watched that corona rise higher and higher in the heavens, with streams of varicolored light—white, red, purple, and, on rare occasions, even yellow and green—flashing up through the arch to form what the Shetland Islanders call the “Merry Dancers.’”’ Sometimes he saw a single streamer, growing brighter and brighter, move swiftly across the sky and fade away. Of course, he had to sit down and write about it. Friends in all parts of the world began Ji as in his experiments Benjamin POPULAR SCIENCE MONTHLY to reply to his questions as to when and how this strange and beautiful light could be seen. Sea captains, back from long cruises, told him that it was unknown in the equatorial region and very rarely noticed in any north latitude less than forty degrees. From Europe, his corre- spondents supplied him with results of observations from the northern countries, where the Aurora sometimes appears in long parallel rays, or curtains, billowing like a greav flag tossed by the wind. Again, from others, he heard of the dis- turbances in the atmosphere, the terrific, unexplainable storms that sometimes ac- companied these heavenly fireworks. IVING a hundred years too soon, he could not, of course, hear of the great storm of 1882 which paralyzed American telegraph and cable wires; burned up switchboards in Albany and Chicago; sent out currents in Bangor, Maine, strong enough to carry a message 700 miles over wire; and finally went off in a blazing Aurora over half the United States, all the Atlantic Ocean, and most of western Europe. Had he come down to our own day, his study of all these phenomena would have made it easy for him to understand that byword among radio enthusiasts—“ static.” From the scientific standpoint, Frank- lin was not long in advancing his theory to account for the Aurora. In the first place, he held that clouds carried electricity and From a Thistle Print, © Detroit Publishing Co. How America’s First Sctentific Genius Pulled Lightning from the Skies, Daring Death to Prove the Truth of His Greatest Idea By ArcutBaALp Doucias TuRNBULL December, 1% ‘THIS fine paint. ing by Charles E. Mills Portrays Franklin in one cf his most attractive aspects — as editor and writer. His ap. peal as both was uni. versal, because he wrote as he talked, not for style but us. ing words as a me. chanic uses his tools that this, under proper conditions, was “condensed” out of them, much as rain- drops are. Up in the Arctic regions were heavy ice fields which, Franklin decided, must block off the electrical discharge and prevent its entering the earth. “But,” he said, “the electrical fire can never be de- stroyed, from which it follows that this must accumulate in great quantity over the ice; as more and more is condensed, this accumulation must gradually fill the whole atmosphere of this Arctic region.” Now, under the heavy pressure condi- tions understood to exist in these same regions, the layer or stratum of atmos- phere, according to Franklin, would be very thin or narrow. Above it, the vacu- um belt must therefore “hang low.” And vacuum, as had already been shown by experiments of scientists, was a good con- ductor of electricity. Suppose that the electrical content of the atmosphere be- came so great that the narrow stratum could no longer hold it; then it must break through. “Running along the vacuum,” cried Franklin, “it will spread in every direction in great rays, diverging as they approach the equator—until the electrical fire finds a more temperate climate and an atmosphere through which it can penetrate, to enter the earth.” f Sanid was Franklin’s explanation, a most ingenious one for his age and day. Modern scientists have their tabula- tions of Aurora observations in various clo in @

Page 29

aint. arles trays le cf Ctive ditor 8 ap. Uni. iked, t us. tools t) as in- re nd he e- is er OF 8s seo <— =. ' a ln Me ie

December, 1926 POPULAR SCIENCE MONTHLY 35

latitudes, their charts of “Auroral frequency,” and their estimates of its height above the earth's general level at anything from eighty to 240 miles. To read them is simply to be convinced that, fundamentally, Franklin was perfectly right. And none of them could beat him at a description. HE idea that clouds carry elec- tricity led Franklin still farther afield in his investigations. We can get one picture of him, sitting at his library desk, making little paste- hoard cloud models. Suspending these from his ceiling, he hung down from them dozens of little silk threads, to which he attached his faithful friends, the bits of cork or wood which had already helped him

A True Romance EW and interesting light is thrown in this, the concluding article of Mr. Turnbull’s series, on the famous kite experiment by which Franklin first drew light- ning from the _ thunderclouds. Epoch-making as this achievement was, how many of us actually could tell any details of it? It makes as fascinating a tale as ever came from fiction writer’s pen. earlier experiments with sharp bod- kins or needles for “drawing off elec- trical fire.” He began to speculate upon what might be done, in this connection, with the charges which he believed to be contained in the clouds. O SEE a vivid, zigzag flash across the sky, and hear the dis- tant muttering or the near-by crash that went with it, was enough to keep his curiosity on its toes. Points —always points; that was what im- pressed him. He wrote to his friend Collinson, the English botanist: “May not the knowledge of this power of points be of use in preserv- ing houses, churches and ships from the stroke of lightning, by directing us to fix, on the highest parts, up-

so many times. Generating electricity with his primitive machine, he discovered that the hanging “particles,” when charged, re- lied one another. If he soaked them with water, they shook off drops as they flew apart—‘‘exactly,” said Franklin, “in the manner of raindrops shaken from the clouds immediately after a lightning flash in a thunder gust.” ROM this he deduced the thrilling theory that two charged clouds “op- posite in fire,” create, when they mect in the sky, the thunder and lightning, and that the large raindrops so often seen were thrown down by the concussion or shock. Of course, we now.know that the big raindrops are not due to the thunder, but to the lightning itself. Franklin was wrong, there, as can be proved by a simple experiment. For instance, if steam is condensed in a large jar, it forms minute water particles on the sides. If an elec- trical discharge is sent into the jar (a brush discharge, for example) the little particles immediately rush together, to form big drops which fall, of their own weight, to the bottom of the jar. The same effect results from such a discharge among dust particles. This fact—that electric discharge makes finely divided matter coalesce or cohere—has been made great use of in the development of radio telegraphy. To go back to Franklin’s day, and be- yond, to the elder Pliny—Pliny, in his Natural History, about the year 50 a.p., spoke of the “flames of light” playing around the masts and spars of the ancient Roman ships. These lights were pop- ularly supposed to be sent by Castor and Pollux, the twin gods who watched over navigators. A pair of such lights was taken to be a sign of fair weather and a good voyage. One light always meant Look out for storms and danger.” GAIN, there were the Spaniards, steeped, as all good sailors are, in superstition. When they saw these lights from heaven, they decided them to be emanations from the body of the holy Saint Elmo. ‘“Corposants,” the Span- iards called the lights, but they are much better known as “Saint Elmo’s Fire,” the common name even today. In those early days, it was natural enough that these phenomena should have a religious or miraculous interpreta- tion. But they depended, of course, upon one very important thing—points. Mast- heads, vardarms, church spires, and so on —all these are pointed. And it is easy to see how their shape supports Franklin’s

Man’s Nearest Approach to Lightning RANKLIN, flying a kite into the thunder- clouds, proved that lightning and electricity were the same. What would he say today of that other experiment, a few weeks ago, when Harris J. Ryan of Leland Stanford University caused 2,100,000 volts to leap a gap of twenty feet in a brilliant ribbon of jagged flame! The picture above shows the bolt—the largest ever produced by man. At right, Prof. Ryan (left) at the control panel, with Allan B. Hendricks, designer of the huge transformers that were used in the experiment right rods of iron, connected by wire into the ground or, on a ship, into the water? Would not these draw the electrical fire silently from the clouds and secure us from that most sudden and ter- rible mischief?” The lightning rod, of course—conceived even before Franklin was sure of the nature of lightning. These suggestions appeared in full in his letters which Col- linson made into the pamphlet, “ Observa- tions for Explaining the Several Phenom- ena of Thunder Gusts.” But one small paragraph of Franklin’s own notes will serve to show how he was reasoning. . OV. 7, 1749. Electrical fluid agrees with lightning in these particulars: 1. Giving light. 2. Color of the light. 3. Crooked direction. 4. Swift motion. 5. Being conducted by metals. 6. Crack or noise in exploding. 7. Subsisting in water or in ice. 8. Rending bodies it passes through. 9. Destroying animals. 10. Melting metals. 11. Firing inflam- mable substances. 12. Sulphureous smell.” From that paragraph of a dozen steps, it is easy to see how he was building his theory and how, as always, he refused to jump to a conclusion. Some of what he said was accepted at once. For instance, Collinson, hearing that Franklin had killed a hen by electricity, tried the same thing on a turkey and reported that “it did eat uncommon tender.” Then Franklin went a little farther. “The electric fluid is carried by points,”

Page 30

36 he declared. “We do not know whether the same property is in lightning. But, since they agree in all the particulars wherein we can already compare them, is it not probable they agree likewise in this?”” And there is a hint of Jove him- self, all powerful Father of Thunderbolts, in the way in which Franklin, at the end of his notes, gives an order: “Let the experiment be made!” Immediately he proposed one method of making the test. “On the top of some high tower or steeple,’ he wrote, “place a kind of sentry box, big enough to con- tain a man and a stand. From the mid- dle of the stand let an iron rod rise and pass, bending out of the door, and then up- right twenty or thirty feet, pointed very sharp at the end. If the electrical stand be kept very clean and dry, a man stand- ing on it when clouds are passing low might be electrified and afford sparks, the rod drawing fire to him from the cloud.” HERE is nothing in history to show that Frankhkin was immediately over- whelmed by a rush of volunteers who wanted the first chance at this type of lofty sentry duty, which perhaps accounts for Franklin’s going on to say: “If any danger to the man be appre- hended (though I think there would be none) let him stand on the floor of his box and now and then bring near to the rod the loop of a wire which has one end fas- tened to the leads, he holding it by a wax handle, so the sparks, if the wire is elec- trified, will strike from the rod to the wire and not affect him.” This, with its provision for at least some insulation, was rather better. But un- fortunately there were no proper towers or steeples in Philadelphia where the idea could be tried. On the other hand, Franklin’s usual free and easy way of telling everything broadcast—through Collinson—resulted in inspiring two Pampered Salmon POPULAR SCIENCE MONTHLY Frenchmen, who took him more seriously than the English Royal Society seemed willing to do at this time. D’Alibard and De Lor, in a pleasant little Parisian garden, set up an iron rod, about an inch in diameter and more than fifty feet high. For days they watched it, while not a thundercloud passed over their heads. Growing tired, they sta- tioned a guard, armed with a length of brass wire and under orders to call them if a storm arose. The storm did come and the guard, without waiting for any- one, touched the wire to the rod. Instantly there was a crash! Sparks flew in every direction. The guard, think- ing his time had come, fell to the ground. His friends rushed for a priest to ad- minister the last rites, but when they returned with him the guard was not dead. Upon that, the priest took up the wire and made several experiments him- self, after which he wrote a report to the two scientists, who seem to have missed the show after all. D’Alibard then de- clared “Franklin’s idea is no longer a conjecture but a reality.” UROPE, including the Royal Society, was almost instantly convinced that lightning and electricity must be identical. Other. scientists began to follow D’Ali- bard’s example in making experiments, not always with happy results. Thus, Professor Richman, of St. Petersburg, erected an insulated vertical iron rod above his laboratory. By a_ metallic chain, also insulated, this rod communi- cated with another in the ceiling. This latter rod projected downward and ended in a ball. The Professor had added an electrometer of his own, consisting of a thread hanging beside the uncharged ball and instantly repelled by a charge. During a thunderstorm Richman bent over to study his electrometer closely. At a heavy clap of thunder, a globe of Get Elevator Service to Ascend Streams q a December, 19% blue fire, large as a man’s fist, leaped frog the ball to Richman’s head, a foot a and killed him instantly. The other m. in the laboratory at the time was stunned that he could hardly say, alte, ward, just how the shock had ‘affected him. With such convincing demonstration, taking place in Europe, it is an odd fag that the only strong skeptic was—Frank. lin himself. It is not fair to say that he was merely chagrined because he had not been the first to try his own experiment: he actually was unconvinced by what had been accomplished. This was not yp. characteristic of the man, because his carefully maintained doctrine of neve being too positive about anything oftey resulted in his having “second thoughts” which appeared to him very much “best,” O HIM, the fact that a rod had been raised fifty or a hundred feet into the air and subsequently electrified did not prove, necessarily, that storm clouds themselves carried this electricity. He held that such a rod could not really reach even a low thundercloud, which was sure to be more than a hundred feet in the air. There could be but one way, he insisted, in which indisputable proof— the only kind of proof that ever fully satisfied Franklin—could be had. That was to send something actually up into the clouds, to see if it would “‘extract the electrical fire.” Looking at Franklin, as we are, from the standpoint of his contri butions to science, this brings us to himat his best and most famous. He had already erected a lightning rod, connecting it to bells that would give sig- nals. When Mrs. Franklin became alarmed by the bells, he begged her to let them alone nevertheless; but he did show her how they could be cross-connected with wire, so they would “ring silently.” In his writings, (Continued on page 158)

LEVATOR service for fish is the newest thing in the fa- mous salmon river regions of Oregon. The _ strange-looking structure in the illustration is a type of the new “‘fish lift’? which probably soon will be a common sight on these rivers. Instinct tells salmon, when ready to spawn, that they must ascend the stream to the farthest possible point to deposit their eggs. And salmon, when ready to spawn, always return to the stream in which they, them- selves, were spawned. But the development of power projects for some years past has been threatening to make it impos- sible for the fish to ascend streams. The new fish elevators invented by J. R. Wheeler, of Reedsport, Ore., offer the solu- tion. Operated by hydraulic pres- sure, the elevator lifts the salmon (and trout too) auto- matically to the stream above a dam. About four lifts are made an hour, and judging by the

crowded elevators, the fish ap- preciate the service! Fish elevator at Winchester, Ore. Shaped like a cylinder, it is eight feet in diameter and twenty feet high. The salmon enter through the lower gate, are lifted, and exit through an upper gate

December K accurat what y out for Loyd | month ScIENC puzzle the fur you he checku find th remar! ability signed tal ag ical al Her

7] m re P A x Met A piece ject pet sign are | es - orig ting part sen: lyti do |

~_=? S&S we

Page 31

all hich feet vay ’ of~ ully ‘hat into the , as tri. n at sig- me let Ow ted 58) December, 1926 ence expert to get a line on your- self. Puzzles can give you quite as accurate an idea as anything else of what your forte is. Especially worked out for this very purpose are these Sam Loyd puzzles, offered from month to month to the readers of PopuLar Sconce Montuty by the greatest puzzle authority in the world. You have the fun of solving the puzzle. And then you have the additional satisfaction of checking up on the time it took you to find the solution, and so arriving at a remarkably accurate rating of your ability at whatever the puzzle was de- signed to test—whether it was your men- tal agility, imaginative power, or analyt- ical ability. Here are eight new ones. Try them! Ye don’t need to go to an intelli- Solutions of Puzzles HE correct solutions for the eight puzzles on this page will be mailed on request, at once, to any reader. Address: Puzzle Editor, Popular Science Monthly, 250 Fourth Avenue, New York City. POPULAR SCIENCE MONTHLY Counting the Years “EJ OW long have we been mar- ried?” inquired McCarthy. His wife gave answer: “I’ve been mar- _ ried to youtwo thirds of my life, but as you are a dozen years older than I, you have been my husband six elevenths of your time on carth.” To make this a test of your aptitude in mental arithmetic, note the time it takes you to give McCarthy his answer in plain figures. Ten min- utes gives a good rating. —————— Mental Carpentry N 8-by-8 square was cut into two pieces, and these two pieces were set to- gether to form the de- sign at the right. You are to reverse the proc- ess—reconstruct the original square by fit- ting together the two parts. You have good sense of form and ana- lytical ability if you can do this in five minutes. ' iii i TigiQdstAsil pearmsveee Prancnpsele Illi Wiidiatabbidgh ! IANA Prone ATL persone a oad a) en HUSA ii Tn USANA Jars for ‘‘Math’’ Stars PON the three shelves illustrated above are twenty jars of three different sizes. They are so grouped as to have the same jar capacity upon each shelf. If the smallest jar holds three pints, many quarts do all twenty of the jars con- lain? Time yourself! Seven minutes to solve _ this test rates you high in mental agility. Fight New Tests—Try Them! They'll Give You an X-Ray of Your Mental Machinery Do You Grasp Facts Quickly? N ONE election district 7200 votes were cast for three candidates. The victor received 100 votes to every 80 cast for his nearest rival, and the second candidate scored 100 for every 75 cast for the third man. How many votes were cast for the winner? You have exceptional ability at group- ing separate sets of facts in their logical relationship, if you solve this little poser within four minutes. A Test of Foresight DETECTIVE, or one skilled at picking his way among devious by- paths, will shine at the test below. This pair of old-style spectacles can be drawn just as shown, by a continuous line which does not cross at any point. Copy the figure without taking pencil from paper and never crossing a line. Twelve min- utes should give you a high rating. yd | 2x2=4 A Simple Trick in Arithmetic HE two upper lines at the left show the only integers that, added together or multiplied to- gether, produce a like re- apply the sult. Now 3+B = «¢ same principle to the lower lines and find the values 3xB=C of B and C. The mathe- matically inclined mind should find the solution One for Your Mind’s Eye F YOU were a realtor and wished to divide the T-shaped piece of land below into four similarly shaped plots, rather than five, how would you re- arrange the fencing, represented by dotted lines? Of course you can do it, but how quickly? Eight minutes in- dicates keen sense of form and balance. — eee ee within eight minutes. APE RMN Building Up Words pS THE test above, you are to exchange one letter at a time from the second row to the first, each exchange producing a different three-letter word which eventually will evolve APE into MAN. The test is to work out the evolution by using the fewest possible words. ARE is the first step, what are the others? 7 | '

Page 32

38 Our Haphazard Roadside Signs Motorists Doubly Protected The mechanical flagman above warns of ap- proaching trains by swinging and ringing a bell. Out-of-order, a conspicuous red blade drops into position. This idea is from California N THE town where I I live there’s a steep hill, with a railroad track at the bottom. The main highway comes to that hill, turns down, and crosses the track beside the station. When a train comes, there’s a great to-do. First, far away, you hear the engine howl. Then a gateman blows a warning whistle. Then he lowers the long gates, striped black and white. Then an automatic warning bell begins to ring. Then the express roars through. That looks pretty safe—for a railroad crossing. So it is, as far as any blind grade crossing at the foot of a steep hill on a well-traveled highway can be safe— in the daytime. But at night the gateman goes off duty. That doesn’t stop the trains any, nor the autos on the highway. But from the time the gateman leaves until he goes on duty again in the morn- ing, it’s a case of catch-as-catch-can. Any morning you're likely to come down that hill and find a brand-new automobile wreck piled up beside the railroad track. Last year there were five. The fact that the crossing is protected during the day makes it all the more dangerous at night, especially for drivers who use it often, because of the reliance you put on the gates. Of course the train whistle and the automatic bell warning that was _ in- stalled in the days of slower moving and less noisy vehicles remain. Also, right beside the track, there’s a big wooden POPULAR SCIENCE MONTHLY They Differ from State to State and Antiquated Styles Dangerous Numbers—Some New Devices By Myron M. STEARNs | cross arm “Stop, Look and Listen” sign to tell the coroner it was a grade-crossing accident. Last winter one woman, driving at night in a heavy snowstorm, became con- fused when at the last moment she sud- denly saw a train coming. She turned directly on to the tracks. By some miracle she got both the children she had with her out of the machine and jumped out herself, before the crash came. Luck- ily, also, the train wasn’t derailed. Many of the less- er-used crossings hereabouts are not guarded by any- thing at all except the old wooden cross arms, set close beside the track. On (Left) Practically the sole protection for an Eastern grade cross- ing. It doesn’t tell when a train is coming FOR GAS OIL i Dangerous advertising signs, make motorists disregard genuine warnings tending to the more used auto roads, during the last few years, small railroad crossing signs have begun to make their appearance, a hundred yards or so before you get to the crossing. That helps a little. And where is this dangerous, anti- quated district that I live in? Just out- side New York City, if you please, where there are more automobiles available for wreckage than almost anywhere else in the world! It’s a condition, however, that’s not by any means confined to the crowded metro- politan area around New York. If you'll drive around a little you'll find motorists not much better protected throughout a good many of the Eastern states. In the West, on the other hand, rail- road tracks are guarded by a wigwag de- vice that has now become commonplace in a number of states. On the Pacific coast and throughout the Southwest, December, 19% Still Prevail in this is used universally. Whenever a train approaches, a red disk starts swing. ing, a red light in the center of it is flashed on, and a warning bell rings. It provides on the whole, a mighty effective warning, The motorists’ railroad crossing sign a hundred yards or so back along the boule. vard is, of course, used also. That amazing discrepancy in warning devices between the East and the West was driven home to me when I took my family across the continent from coast to coast. It was only one of a number of almost equally startling discrepancies that we noticed, that left me wondering why warning devices and other safe. guards that have been proved highly suc. cessful in some states aren’t adopted in others. ODAY, for instance, after the grade crossing wigwag has been demon- strating its superiority on the Pacific coast for something like fifteen years, you will find, in the Grand Central Terminal at New York City, a flashing red light installed, as a sample of what is advo- cated for use at all grade crossings. Because of its similarity to other blink- ing signal lights, because of its lack of attention-catching motion, because it’s so much less noticeable by day than at night, it is utterly inferior to the familiar warning of the West. How anybody can advocate its use instead of the wigwag is a mystery. We left New York early in December. Eighteen days later, going by way of . Texas to avoid the cold, we were in Los Angeles. Two hundred miles a day— and we learned a lot about motorists’ warning signs that fail to warn and safe- guards that fail to safeguard. Coming back in the spring along a more northerly route, we learned some more. Signs and safety devices for the pro- A “dangerous hill” sign that prevents many accidents when roads are slippery from rain Decemt tection group warnll signs; and he Tra was di tion t and hi behin« The the g above M lines at al have safeg foun ing P wher consi copie othe Up} road ridet to ct and adm a tir wes! the var was we we whe you ing

Page 33

ra ng. les, ng, ile. ing est my “ies ing ife. er. OS ts’ fe. December, 1926 tection and convenience of motorists up themselves under four heads: warning signs and safeguards; route signs; speed laws and traffic regulations; and hand signals. ; Traveling across-country as I did, I was dumfounded to find how much varia- tion there is in all four of these classes, and how unbelievably far some states are behind others in adopting the best. ' The warning signs and devices, like the grade-crossing signals described above, are the most important of all. ARYLAND was one of the first states in the East to put white lines down the center of the boulevards at all curves. Gradually other states have followed suit until that particular safeguard is now widespread. But we found in Maryland, also, signs prohibit- ing parking at curves or dangerous spots where the white line in the center was considered necessary. Obviously a wise -recaution—but have the other states copied Maryland in that, or in a lot of other sensible road regulations? You can answer from your own experience. Up in my neck of the woods. where the roads are crowded with week-end glory- riders from New York City, vou're likely to come around a sharp corner anywhere and find half the road blocked by an admiring family watching father change a tire. In parts of Ohio and some other mid- west states, we found a line running all the way down the center of the boule- vard, instead of just at the curves. It was a decidedly good thing. Every time we passed another car we knew whether we were On our own side of the road, and whether the other fellow was on his. If you don’t believe that’s a help, try pass- ing a couple of big interurban busses in Pennsylvania or New Jersey, or maybe a ten-ton truck. Other states, apparently, had never heard of Ohio’s common sense line. When we left that section of the country we left that road-center safety line behind, and we never found it again until we got back there. LSO, in Ohio, we found in places a white line at the edges of the road— one of the greatest safety devices for night driving you can possibly imagine. Why don’t other districts try it? When a state or county goes to an expense of twenty or thirty thousand dollars a mile—and sometimes more—for concrete boulevards, why begrudge a few hundred dollars for paint and road signs to peake its expensive road safe to travel on! Road signs! There has been a tremen- dous improvement recently in regard to them, it is true, and the slow states, at last, really are beginning to try to catch up. Already many states have installed curve, crossroad, and other warning signs on all main boulevards; though they're slower at taking up the safety directions for stretches of road that require un- usually careful driving. Maryland—one of the leading road-posted states—has directions at the tops of all dangerous hills, giving, usually, the length of the hill, and telling you what gear to descend m. There are flashing lights and reflec- tors at curves and crossroads for night POPULAR SCIENCE MONTHLY r : (Left) to read. New York. (Below) A danger sign that is coming into wide use. It has a mirror with a red glass front. At night an approaching auto headlight is reflected in it, giving the red light, a danger signal 53} (Below) In Texas most main route signs are clearly marked. Here even a small culvert has been put to work driving, and top-of-grade blinkers of a different color that supplement the day- light warnings. But have those simple, sane precau- tions been taken in your vicinity? They haven’t in mine—nor in hundreds of other districts we passed through. You can slide over the top of that hill I spoke of in my own town, with the bad railroad crossing at the bottom, without a word of warning. You're supposed to know about it already. Our roads were made for us to drive on, and visitors use them at their own risk—or so we tell them, in effect. Yet in California they put up signs reading: “Caution—Hill Slippery in Wet Weather.” Signs like that, obvious- ly, are not for motorists who know the hill, but for strangers who don’t know it. Road signs, in the old days, were put up high. That was so they could easily be read from the top of a load of hay, I Kansas takes no chances— her signs are easy (Below) Dangerous curves are also marked in The signs, however, are not so easily read as the Kansas type (ee LE, (Above) Within fifty miles of New York City you still find important intersection signs like the above that you must take a day off to read > a (Above) A tried safety idea—the white chalk line, keeping motorists on the right side of road suppose. Maybe horses could see them easier, too, and the drivers of hansom cabs. But autoists sit relatively near the road. A sign three or four feet above the ground is easier for them to read than one six or eight feet up. Most of the states have already discovered this. Yet an amazing number of them still put the signs clear up in the air for hay wagon drivers. California, though ranking with Maryland as one of the best posted states in the Union, is still a surprising offender in this respect. ISLEADING advertising signs cause serious accidents and con- sequently have been legislated against already in many states. In others the danger still persists. Imagine coming down a boulevard to a sign that reads— as many signs do— STOP! For Gas and Oil You are rolling thirty-five, we'll say, and you pick up that STOP long before you see the little words under it. So you pull your (Continued on page 161)

Page 34

Remarkable Camera Magnifies Steel Speck 15,000 Times POPULAR SCIENCE MONTHLY A world’s-record in minute photography was set by Dr. R. G. Guthrie, of Chicago, when he recently magnified a particle of steel 15,500 diameters. The camera, shown above, did not vibrate by a two-thousandth of an inch during the hour-and-a-half exposure On these pages are presented each month brief stories of scientific discovery and research hav- ing practical bearing on our everyday problems. Mystery of 500,000 Years Ago in ‘‘Missing Link’’ Skull ATERIAL for piecing together an- other fascinating chapter in the story of man’s origin on earth comes from Trinil, in Central Java. There Pro- fessor Heberlein of the Netherlands Gov- ernment medical service has just dis- covered the complete skull of the strange manlike and apelike creature who lived half a million years ago, called by scien- tists pithecanthropus erectus, and popu- larly termed “the missing link.” The latest discovery was made near the spot where, in 1892, Prof. Eugene Dubois of Amsterdam University first found frag- ments—a skull cap, two teeth, and a thigh bone—of this earliest known crea- ture resembling man. Scientists who have studied these fragments believe that pithecanthropus erectus was not a direct ancestor of man, but rather a cousin of the human race many degrees more hu- man than any of the manlike apes. A study of the complete skull, including the all-important skull base, may go far toward bridging the mysterious gulf be- tween man and the ape. At the same time, it may serve either to substantiate or reject the astonishing theory recently advanced by the German anthropologist, Dr. Max Westerhoefer, that the apes are really descendants of ancestral man. Would Set Snakes to Kill Rats F YOU are troubled by rats, gophers, or other harmful rodents, why not try keeping a pet snake or two about? In experiments in the zoological labora- tory of the Kansas State Agricultural College, Prof. Frederick L. Hisaw and Howard K. Gloyd have determined that the bull snake is death on rodents, and as such is a real benefactor of the farmer. After a study of forty of these snakes, kept in large sunny cages, they found the reptiles to be “‘gentle, easy-going crea- tures, quite unappreciated.” The experimenters put live rats into the cages of the “pets” and observed how the snakes captured their prey, and how much of such food each consumed. ““A bull snake weighing about three pounds eats more than three times its own weight in rodents in the course of six months,” Professor Hisaw reports. Up with Science Motors Run by Cornstarch and Bridges Sprayed How Uncle Sam Tests Plasters Why do some wall plasters crack and peel, while others remain intact for years? Bureau of Standards experts are trying to find out. Different kinds of plaster are applied to sec- tions on the laboratory wall as shown above, and tests are made to determine their qualities Cornstarch to Run Our Cars? Floating dust, it has long been known, may explode with consider- able violence. Now science is trying to use the same principle to find a new motor fuel. The photo shows Dr. W. A. Noel, of the De- partment of Agricul- ture, pouring corn- starch into the intake of an automobileengine specially arranged for these experiments December, 19% -with Metal This is equivalent to twelve adult pocket gophers a year. One three-pound snake should be able to clear an acre and a half of alfalfa land of rodents.” One five-foot bull snake might save g farmer $3.75 a year, he estimated. Tooth Decay Prevented by Diet of Fish and Cabbage EFORE many years the dreaded visit to the dentist may be a thing of the past. In place of drillings and fillings to preserve the teeth, we may substitute an easy diet of fish and cabbage. Such was the recent prediction made by Dr. Bernhard Gottlieb of the Univer. sity of Vienna to the International Dental Congress at Philadelphia. Tooth decay may be prevented by eating certain foods, he declared, and within five years the dentists hope to have enough scien- tific data to present a definite tooth- preserving diet. “We have found,” he said, “that weight-giving food which builds up the body tissues does not feed the teeth, and we have been trying to isolate foods which will do so. Experiments with sea foods have encouraged us to believe we are now on the right track.” He named cabbage, brussels sprouts and spinach as other valuable tooth ‘ builders besides fish, for the reason that they contain lime salts which are the basis of tooth enamel. Cancer Called Nonhereditary NE by one the deadly diseases which afflict mankind fall before the ad- vance of research workers and scientists who devote, and sometimes § sacrifice, their lives to the cause of health. Now more than a hundred. specialists from is ite ate 2 np nee An

Page 35

ket ake half ea its th at he December, 1926 eight countries have combined in unani- mous agreement on fifteen important conclusions regarding one of the most dreaded diseases of all times—cancer. These specialists, including physicians, pacteriologists, surgeons, and experts on radium and X-ray, met at Lake Mohonk, N. Y., a few weeks ago under the aus- pices of the American Society for the Con- trol of Cancer. Most important of their conclusions were: 1. For all practical purposes cancer is not contagious or infectious. 9, Cancer itself is not hereditary. 3. Surgery, radium and X-rays are the only justifiable treatments for cancer. 4, Cure depends on treatment in the earliest stages. Cancer in some parts of the body can be discovered at a very early stage, and people should be on guard to recognize the danger signals. Dentists can help by knowledge of the causes of cancer, the experts agreed, especially with relation to imperfect teeth and badly fitting den- tal plates. Many lives, they empha- sized, could be saved which now are sacrificed to unnecessary delay. Man Can Be Beardless and Bald —If He Wants To HE time may come when men, if they want to, can relieve themselves of the bother of the morning shave, and when women won’t need to worry about bobbed hair any more. This promise is held out by H. C. Brooke, English naturalist, as the result of experiments in the regulation of hair growth. Hair, Brooke says, is purely a matter of heredity. In his experiments he produced a strain of mice whose heads became bald in sixteen days. A few days later they lost the fur on their backs, and a little later all their hair! In Germany another scientist, Felix Pinkus, has been finding out just what happens in the life of a hair. For seven years he kept a record of one of his hairs. He found that it grew only 264 days in a year. In summer it grew for 140 days, while in winter it rested after 124 days. In summer, he found, hairs get a quarter of an inch longer than in winter. An Important New Steel TEEL that would be soft enough to shape easily, yet with a surface hard enough to withstand the wear of moving POPULAR SCIENCE MONTHLY How Huge Cables Are Tested Said to be the largest cable tester of its type in the world, this 1250-ton ma- chine was built recently for English bridge builders. Right: Huge cables being fixed into the crosshead for tension tests. Dials record the breaking point. Below: Examining the ends of cables broken under terrific tension *. pil gg esate: yy : » 9. parts, long has been the dream of machine builders. Heretofore the steel used in moving parts has been hard throughout, and difficult and expensive to “work.” Now a new steel has been produced at last by metallurgists of a Pittsburgh steel corporation, which has a soft core with a hard surface “skin.” The discoverers predict that “‘jalcase,” as the new steel is called, will greatly reduce production costs and speed up output of parts for automobiles, washing machines and other household appliances, typewriters, adding machines and machines used in the manu- facture of clothing. New Rays from the Stars sacs rays coming from a certain group of stars, far more powerful than X-rays, have been discovered by two Swiss scientists who braved the bitter cold of a mountain peak for a month to make their remarkable discovery. On the sum- mit of Monch Mountain, at an altitude of 13,465 feet, a small tent has served as ob- servatory for Dr. Kolvorster and Dr. Deesalis, who despite the Arctic tempera- ture have made un- ceasing astronomical observations, ending in the discovery of the He Sprays with Molten Metal The photograph at the left shows a metal gas burner being coated with “metal paint”’ by a remarkable new spraying process re- cently invented in Eng- land. The “paint” is wound around a large spool in the form of wire, which is melted and sprayed on the article. Steel bridges and ships, it is predicted, will soon be painted with metal by this easy process new and as yet unnamed strange rays. These untiring scientists hope to harness and use the extraordinary new rays for scientific and therapeutic purposes. The intensity of the cold finally forced the men to descend to Interlaken, where they made known their discovery. The Best Buys in Meat OME surprising things about the food values of things we buy and eat re- cently have been revealed by experts on nutrition. For instance, Dr. A. T. Edinger, of the University of Missouri Agricultural Experiment Station, who has made a special study of the American bill of fare, tells us that the cheaper, tough cuts of beef contain more value in calories than the expensive bits, and that in fact the “choice” porterhouse steak is the worst buy of the lot. He has found that a rib roast is more economical than a loin roast, and that a clod or chuck produces the most boneless meat at lower cost than any other roasting portion. If your wife asks for a piece of beef off the “‘plate,’’ he ad- vises, she will get the best bargain of all. In general, he adds, it is best to buy from a piece of meat that is only medium fat, for this provides the largest amount of protein or muscle-building material. From the department of nutrition of the American Institute of Baking comes the interesting information that an ordi- nary ham sandwich, if topped off with a glass of milk, is “‘a complete food.” In Air Mileage U. S. Leads World YW we frequently hear it said that Europe leads the world in air transportation, in at least one point it is far behind the United States. Total air mileage in the United States over a period of a year now doubles that of France, the most active European nation in aviation. This estimate comes from Archibald Black, consulting air transport engineer, of Garden City, N. Y., and is based on statistics compiled by the Aeronautical Chamber of Commerce. These indicate that air mail and passenger routes in this country, when a year’s operation for all has elapsed, will approximate 6,000,000 miles, as compared with 3,000,000 miles covered by regular air routes in France during the same period.

Page 36

POPULAR SCIENCE MONTHLY December, 19% Phrills of Modern Explorers Sand storms and bandits make deserts still perilous —Power from ocean tides—How insects provide for their children—Reviews of some of the new books “On the Trail of Ancient Man’’ By Roy Chapman Andrews. Published by G. P. Putnam’s Sons r “HE North Pole has just been flown over; Beebe has delved into the sea; the Roosevelts have climbed the roof of the world. And now comes the story of another thrilling adven- ture of modern explorers, the American Museum of Natural History’s exploration of the Gobi desert in Mongolia. In his book, Mr. Andrews, leader of the expedition, tells of some of its exciting experiences. Bandits who attacked the scientists were routed by the charge of an automobile with cut- out open. Their frightened desert ponies ran away, rearing so madly the bandits could not even unsling their rifles to reply to the shots from Mr. Andrews’ revolver. Another time the expedition was nearly buried by a sand storm swooping across the desert, “an ominous tawny bank advancing at race horse speed.” Trying to walk through it was like pushing into a “fantastic yellow wall, which gave and closed behind as one advanced.” Most of the party “rode it out” lying on the ground in the battered tents, faces buried in wet cloths. Walter Granger, chief paleontologist, was buried to the neck in a pit. After an hour the gale dropped suddenly into flat calm. Then, after camp had been shoveled out, the tawny cloud appeared again. This time it was a sand spout that whirled around for five minutes as if trying to suck tents and all into the vortex, then danced away across the plain. For ten days after there was never enough calm to make it worth while to clean up either camp or campers. In late May, two adventurers fought for three days through a blizzard and its aftermath of snowdrifts to Urga, just after leaving a camp that lay drenched in heat waves. T ANOTHER camp,a swarm of poi- sonous pit vipers invaded the tents at night. The snakes coiled about all four legs of camp cots, about shoes, and gaso- line boxes. A Chinese chauffeur killed one, then picked up his cap and another fell out of it. Dr. Loucks put his hand on one lying on a gun case. Luckily the cold had made them sluggish. After dark all walked about with flashlights in one hand, pickaxes in the other. Andrews and Mrs. Andrews had a narrow escape from the shaggy black Mongolian wild dogs that feed upon dead natives and will attack the living. They By Tuomas *M. Jounson awoke one night to find a grewsome circle about their sleeping bags. The dogs attacked one member of the party and he had to kill two. Other animals were more agreeable. Many of them were so curious they would chase an automobile to see what it was. In a short dash a gazelle could beat the From “‘How Insects Live” Beetles Rolling Their Food A devoted couple of sisyphus beetles engaged in the task of providing food for their family. The father, upside down, is pushing with his hind legs, while the mother clutches the ball, moving backward. Later they bury the ball car, for it made sixty miles an hour. The wild asses made forty. As a result of its discoveries, the ex- . pedition offers the conclusion that Asia is mother of the continents, whence reptiles and mammals spread to Europe and America. It predicts that “a relatively large-brained, erect-walking ancestral type of man” will eventually be discovered there, in proof that Asia was the chief center of humap origin. ‘How Insects Live”’ By Walter Housley Wellhouse. Published by the Macmillan Company HEY live in mysterious ways and very interesting ways, according to Mr. Wellhouse. As witness, the sacred scarab beetle, valuable not only as model for the jewelry trade, but as the original pushball player, at least of the insects. The scarab makes his own ball, of refuse, and about as big as an apple, and so bigger than himself. He pushes and pulls it—mostly pulls it—about, looking for a good place to bury it. When he does, he digs a hole, rolls the ball into it, climbs in after the ball, and plugs up the hole after him. Then he has a big feed, spend- ing days and nights eating up the ball. When all his buttons are strained, he comes outagain, tostart a new ball rolling. The female scarab beetles hide their eggs in similar balls and then bury them. When the young ones hatch, they eat the ball and then emerge into the upper light and air of competitive life, where they have to roll their own. Slightly more grewsome is the trick of the digger wasp. It buries its egg with two dead caterpillars, to feed the little ones. After burying the egg, it hammers down the ground with a pebble. The cicada lives in a hole in the ground, sucking sap from roots to get strength for a brief day on earth. Crickets, ants and katy- dids hear with their legs. These are only a few of the fascinating things this book tells of the in- triguing ways of insects. ‘The Tide”’ By H. 1. Marmer. Published by D. Appleton and Co. AN water take the place of oil? Does the rise and fall of ocean tides generate power enough to replace that of the American gasoline supply? Mr. Marmer thinks that tidal power may some day become of real importance in propelling a civilized and mechanized world deprived, in part or wholly, of its coal and oil. He is assistant chief of the division of tides and currents of the Coast and Geodetic Survey, but says, nevertheless, that those optimists who predict that once the tides are harnessed they will make the whole world go, are wrong. Development of tidal power is not economically feasible where the average tide range is less than ten feet, Mr. Marmer finds; and development of large power is not feasible unless it is twenty feet. There are only fifteen such places in the world, and only one of them is in the United States, the St. Croix River, Maine. Greatest is the Bay of Fundy, the arm of the Atlantic separating the Canadian province of Nova Scotia from New Brunswick and the state of Maine. Here the tide rises forty to fifty feet in six hours, then falls again in another six. HEORETICALLY, the maximum horsepower available where the tide rises ten feet is 7200 per square mile of tidal water; when it rises twenty feet, 28,800. So in a basin of twenty square miles and twenty-foot range, the theo- retical maximum horsepower would be 576,000. Practically, only a fraction could be utilized. The only system that holds possibil- ities of providing big power plants, we learn, is the basin system. It consists of one or more basins cut off from the ocean by dams. Asthe (Continued on page 163)

Page 37

December, 1926 July First Prize O MAKE certain of finding all the mis- takes of John and Mary and the artist in our July Picture Contest, Harold Stewart, of San Diego, Cal., built from odds and ends a model stairway and POPULAR SCIENCE MONTHLY icture Contest Winners Second Prize “Such puzzles as these are good to keep the cobwebs off the brain,” says C. R. Helper, of Sturgis, Mich., winner of the second prize of $100. Mr. Helper is a _cabinetmaker whose diversion is puzzle solv- ing, “including with it,’’ he writes, “‘the added recreation of beating carpets, washing dishes, and mowing the lawn” balcony like the one shown in the contest picture. “What a glorious unveiling of mistakes as the model progressed,’’ he writes. His completed handiwork came as part of his entry, and the judges have awarded him the first prize of $500. Mr. Stewart is an insur- ance salesman, and lately reached his 3lst birthday Third Prize The $50 prize won by Egbert C. Everest, of Plattsburgh, N. Y., goes to a worthy cause. “I shall use it toward my daughter’s col- lege course,” he tells us. Mr. Everest, besides being an attorney, is quite a handy man with tools Others Having entered each of the previous Picture Con- tests, E. A. Oliver finds that ‘‘ persistence wins.” He resides in Los Angeles An instructorin man- ual training at La Crosse, Wis., Matt J. Hefti found the Con- test offered many valuable suggestions Starting the contest “just for fun,” Mar- Mrs. John Kruger, of Toledo, O., had a val- uable assistant in her husband who, she says, “delights in tinkering’”’ Flocken, M.A., is head of the department of math- ematics in Wilbra- ham Academy, Wil- braham, Mass. Solv- 1 Louis C. guerite Goepel, Or- lando, Fla., became so fascinated that she spent many hours to make her list complete ing puzzles is his hobby. Here he is with his little son Alfred T. Renfro, Belle- vue, Wash., who won the first prize in our April Con- test,is back again a winner. Here he is with his daugh- ter enjoying his vacation TURN TO PAGE “*My wife shares in the honors, for we worked together,’”’ says Harry R. Samuelson, a press- man in the Govern- ment Printing Office, at Washington, D. C. Ruth Laura Winders, Co- lumbus, O., found a lot of mistakes by re-drawing the contest picture. Mr. Wind- ers is justifiably proud of her 164 FOR THE COMPLETE LIST Clement Birch, Joliet, Ill., proved to his own satisfaction the theory that the brain works best around midnight. That is when he found most of the mistakes “The Picture Contests,” writes Carol Young Alwin from Minneapolis, Minn., “were an incentive in de- veloping the power of ob- servation.” Sheis an artist OF PRIZE WINNERS FOR JULY

Page 38

POPULAR SCIENCE MONTHLY December, 1926 New 4irplane Built Like a GULL Inventor Studied Long-Winged Birds to Find New Secrets of Power and Speed L. W. Bonney, inventor of the sea gull airplane, holding aloft the stuffed bird he used as a model. He caught and studied many gulls before picking this one as ideal in its proportions UILT like a sea gull B in soaring flight, this remarkable new type of airplane was designed by Leonard W. Bonney, of Flushing, N. Y., after a plaster cast of an actual bird. The wings, shaped like a gull’s, can be folded back by pressing a hydraulic lever in the cockpit. At the instant the wheels | touch the ground in landing, the wings are drawn back, placing the plane’s entire weight on the wheels and enabling it, according to the theory, to be brought to rest within a few feet, even in a back yard. The ordinary plane must taxi across a landing field a considerable distance be- fore it can stop. Mr. Bonney’s flying experience dates from 1910, when Orville Wright taught him to fly. Now 42 years old, he has been an aviation enthusiast ever since. For two years he studied the flight of birds, He’d Wrest Power peg that would utilize the power in the up-and-down motion of ocean waves have long inspired in- ventors. One of the latest is the wave- harnessing machine illustrated here, and its inventor, Ar- convinced that aviation still had many secrets to learn from their methods. Decid- ing finally upon the sea gull as his siete, he caught a large number of them, measuring “their wing spread and the weight they could carry. One specimen which in every way measured up to his ideal requirements became the original pattern for the plane. Swooping down to earth and landing with its wings folded, the Bonney Gull, as it is called, may be wheeled into an ordinary garage, so little space does it occupy in this position. Folded or ex- tended, the wings are held rigidly in Left: The inventor in his still unfin- ished plane. Be. low, a rear view, showing the wings folded. This feag- ture is designed to permit the plane to be landed in ag back yard and then run into a garage eee Zz position by gun locks. In flight, the machine is balanced and guided by the flexible wings, which will adjust themselves to keep it on an even keel. A supply of gasoline is carried in a tank fastened to the outside of the plane at the front of the fuselage, directly under the propeller. Within the body, the cabin resembles the interior of a motor car. A seat for two passengers is covered with a stream- line top that enhances the graceful lines of the remarkable craft. from the Rise and Fall of Ocean Waves the inventor says, he stores up enough energy to run it for twenty-four hours. It can be used practically by ships at anchor, he declares, or to operate danger signals, buoys or lighthouses. With a machine developed from his present model, Mr. Adams has under- taken to light up a pier now under con- struction at Venice, Calif. The floats used are shown at the right. thur T. Adams, of Los Angeles, Calif., is confident that a_ practical working type of it will make power as cheap as air or wa- ter. He has worked en the model pictured here for more than three years. The working principle is a number of springs which are tight- ened by the con- stant up-and- down movement of floats placed upon the water. By operating the apparatus for five or six hours a day, wonesagiie:” Floats that tighten springs as they rise and fall with ocean waves are the basis of this unique Left: A. T. ime, the inventor, with the springs, “power Right: The type of floats used rathe haile in th has subs this an ¢ Lan inve Elec of hy stab rate Whe the liber 7 heat welc is re pass twee and mol ic h atol hea’ crea hyd pert hyd Toa of | cen the the X bri the me int seg ral

Page 39

December, 1926 Latest Arc Welding Feats. Amaze Engineers POPULAR SCIENCE MONTHLY Joints Made by New and Speediest Process Fail to Crack under Terrific Tests HE new method of welding—by means of an atomic hydrogen flame rather than an oxy-hydrogen flame—is hailed generally as an important advance in this construction method, which lately has come to be regarded as the ideal substitute for the noisy riveting hammer. Like many other important discoveries, this invention is the result of research in an entirely different field. Dr. Irving Langmuir found during laboratory investigations for the General Electric Company that two atoms of hydrogen gas, forming the more stable molecule, could be sepa- rated under high temperatures. When they combined again to form. the molecule, intense heat was~ liberated. The utilization of this intense heat became the basis for the new welding apparatus. The hydrogen is reduced to the atomic state by passing a powerful electric arc be- tween the two tungsten electrodes and directing a jet of the gas in its normal molecular state into the are. As the atom- ic hydrogen is blown out of the arc, the atoms combine into molecules and the heat generated in this way greatly in- creases the temperature of the burning hydrogen. This heat is said to be fifty percent more intense than the oxy- hydrogen flame now in use for welding. Magnetism Now HILE defective rails are known to be responsible for disastrous rail- road wrecks involving huge _ losses of life and property annually, until re- cently there was no means of detecting the hidden flaws in the rails, which caused these catastrophes. Now a Japanese engineer, M. Suzuky, brings forward an invention perfected in the laboratory of the Japanese Govern- ment Railways at Tokyo, to detect such internal defects as transverse fissures, segregation of impurities, and so on, in rails. The defectoscope, as it is called, Photos Courtesy Engineering News-Record How the electromagnet is placed by means of rollers on a rail to find hidden flaws. The exploring coil, between the poles of the mag- net, is shown in enlarged view at the right Above: Sample of welding, show- ing how metal welded by the new process does not crack when bent The gas is supplied to the electrodes, which are in contact when not in use and are adjusted by a screw, through a tube in the handle under a pressure of less than a pound to the inch. In addition detects these flaws by magnetism. It con- sists of two parts: a powerful electromag- net which creates a magnetic flux in the section of rail under test; and an exploring coil, working on an entirely separate cir- cuit, that records any variation in the magnetic flux. This is the brains of the apparatus, So long as the flux remains constant, as it will in a perfect rail of uniform cross section and density, the exploring coil will 45 Above: Welding a piece of casting by the new atomic hydrogen process. Left: Close- up of the torch, showing the two electrodes to the gas supplied to the electrode tips, a quantity is ejected to surround the parts to be welded. This prevents the formation of oxide or nitride films which make the ordinary are welded metals brittle. Welds made by the new apparatus, it is said, do not crack or break under the twisting and bending tests, and are made far more rapidly. Detects Rail Flaws That Caused Wrecks be electrically “dead”? and will show no reading on the attached galvanometer, an electrical instrument for measuring minute electric currents. If a flaw is en- countered as the magnet rolls along on its own wheels, the magnetic flux will sud- denly drop and return to normal again, inducing a current in the exploring coil which the galvanometer records. In this way the slightest flaws may be detected before they become dangerous. With this outfit about 100 rails can be tested in an hour. Section of a rail, showing The defectoscope in action, mounted on its car and in posi- Electromagnet B on the rail re- ceives current from batteries A. C is the recording apparatus tion on railway tracks. a bad split and trans- verse fissure. Hidden flaws can easily be de- tectedby thedefectoscope

Page 40

46 POPULAR SCIENCE MONTHLY Ingenious “Gun” Splits Logs into Cordwood

Log-splitting gun, already in wide use in farm- ing and lumbering regions of the Northwest Forests Sown from Airplanes WO men scattering tree seeds over devastated land from an airplane can accomplish as much in one and a half hours as two men working on the ground could in ten years, according to an experiment conducted by the Army Air Corps in Hawaii. <A large area devastated by fire, where seeding by hand was found impracticable, was replanted in this way. Three trips were made over the burned area by an Army aviator, carrying twenty- four bags of seed. Musical Tree Plays Christmas Carols

ONSTANT- LY revolv- ing so that the tinsel glitters and shines, a Christmas tree set up in a re- cently invented musical tree holdersendsforth tinkling Christ- mas carols, much like the old-fash- ioned music boxes. The hold- er plays twenty- fiveminuteswith- Holder will support a pete out winding. tree six feet in height _His Plane Won’t “‘Crack Up” WO novel safety features were in- corporated by D. E. Dunlap, aero- nautical engineer of Dayton, Ohio, in a new airplane recently designed by him. Two pusher type motors are used, placed at each side of the pilot, and the nose of the fuselage is rounded off, so that the plane will simply roll over instead of breaking up and crushing the pilot and passenger under the weight of the engine in case of a bad landing. F ghd large tree, after being felled and sawed into four-foot lengths, can be split up easily and quickly into cordwood by the use of a remarkable new instru- ment known as a splitting gun. The “gun” resembles a heavy metal pin. The driving end is solid and the muzzle end, which is slightly tapered to facilitate driving, is hollow. About a tea- spoonful of black blasting powder is poured into the hollow end, and after a fuse is fitted, the splitting gun is driven into the end of the log. The protruding rear end is supported against a heavy piece of wood. Driving the gun into the log tightly compresses the powder, and when it is fired by means of the fuse the gas is driven forward and its expansive force blows the log into at least two pieces. Ordinarily about two minutes are re- quired, it is said, to load the gun, drive it and set it off.

Umbrella Folds in Vanity Case EING overtaken by a sudden shower is no calamity to the woman whose vanity case is this latest novelty from Germany, shown above. Face powder, puff, and rouge rub elbows companionably with the handle and collapsible ribs of an umbrella. When folded, the umbrella fits compactly into the top of the case. The phonograph photographed in comparison with a ten-inch record

All That Makes a Phonograph —Less Than Two Inches High MALL enough to be carried in a coat pocket, the remarkable little ‘phono- graph above is the product of an English factory. Its dimensions can be appre- ciated by comparison with the average size disk record shown. ‘They are: diameter, four and one half inches; height, one and three quarter inches, and weight, two and three quarter pounds. In all essentials, it is said, the little instrument follows the construction principles of the ordinary talking machine. Building Stone from Brick Waste Y A new process for making building stone from brick waste invented by two Swedish engineers, the waste bricks are first crushed to small lumps and sifted. The finer part is ground to a powder, mixed with lime or cement, and water added, making a mixture the consistency of a plastic mortar. To this is added the coarse material obtained from the first grinding of the bricks. The resulting mixture, when dry, is said to be an ex- cellent substitute for natural stone. AT A HOTEL in Berkhampstead, England, recently, twenty couples danced to music which could not be heard by the specta- tors. The music was broadcast from a near-by radio station, the dancers carry- ing their own radio receiving sets, equip- ped with small inconspicuous headphones. New Folding Boat Seats Two Rowers OLDING boats have long been popu- lar in Europe, where it is no uncom- mon sight to see them being carried from one to another of the many small rivers. A new folding boat The framework is of steel, covered with canvas, and the entire boat, folded or ready for launching, is said to be light enough to be carried with ease.

that can be easily dis- mantled and placed in boxes as small as those illustrated below, is the recent invention of Karl Steiner, a young German.

Left: Starting to put together the folding boat., The two boxes hold the entire boat, and the assembling is said to be the work of a few min- utes. Above: The completed boat, light enough for a girl to hold aloft

Page 41

Cuff Link Watch the Latest Style in Timepieces HIS latest mode of wearing the watch has been introduced in Ger- many as a substitute for the wrist watch. It is a cuff link timepiece, and fairly accurate in spite of its diminutive size, it jsclaimed. One advantage it has over the wrist watch is that the shirt sleeve doesn’t have to be drawn up part way to the elbow in order to see where the hands are pointing. The link on the other side is hinged, and folds flat against the connecting bar, to permit easy insertion through the button- holes. Searchlight Stops Auto Thefts LICE officials of Worcester, Mass., recently announced that the number of automobile thefts in their city has been cut in half by the use of a huge 30-inch searchlight of 43,000,000 candlepower. This light is placed on the top of a tall building, where it can be seen a long distance. Officers are instructed to watch for signals flashed by the light whenever a theft is reported, and to go at once to the nearest patrol box for details of the robbery. The light then is turned on the section of the city where . the theft occurred, aiding in the capture of the criminal. POPULAR SCIENCE MONTHLY 47 Giant Camera Snaps a Whole City at Once ESIGNED for Army Air Service work, this huge aerial camera is being tested by Lieut. George W. Goddard at Dayton, Ohio. The lower end shown in the illustra- tion houses the largest photographic lens of the high speed, anastigmatic type that has ever been ground. The image re- corded on the film is nine inches square. At an altitude of 35,000 feet, the lens would pro- duce an image showing a city the size of Detroit to be about three and one half inches long. Broken wire is held with pliers as illustrated above while the grooved device splices the loose ends Machine Shows “Dub” Golfers How to Putt ECAUSE so many golfers, even ex- perts, are weak on the putting green, P. A. Vaile of Chicago, noted sports authority, has perfected a practicing ma- chine which, he declares, forces one to go through the difficult putting stroke in per- fect form. He also has devised new exercising apparatus to develop the golf- er’s muscular strength and control. The putting machine, at the right, consists of an upright sup- shaft of the club is at right angles to the direction the ball should take. This, according to Vaile, is the only way to impart a true roll or “run” to the ball. Other new apparatus includes special leverage dumb-bells (at the left), which are weighted to require unusually tight grip and so develop the wrist muscles, and a bar-bell (center) with an adjustable weight to develop shoulder and arm muscles. porting a pivoted clamp that holds the tip of the shaft in such a way that the club, when gripped by the student, swings like a pendulum. The club also strikes the ball when the New leverage dumb-bells are weighted to require a tight grip, strengthening wrist muscles - Above: Practicing the putting stroke with mechanical aid. At left: Developing arms and shoulders with weighted bar-bell Lieut. G. W. Goddard and W. Oswald with the huge camera Wire Splicer Designed for Telephone Linemen HE broken strands of telephone or other small wires can be spliced in a few moments, it is said, with an instru- ment invented by Niel Kjesbu of Silver Creek, Wash. A short piece of steel is drilled and grooved so as to catch the broken ends, which are then twisted into a splice. The inventor claims his device is adaptable to the needs of telephone line- men who have to work in awkward posi- tions on the arms of telephone poles. The splicer is slipped on to the line at the point where the broken strands are crossed and held, and one of the ends is caught in the groove. When the instru- ment is twisted, the broken end is firmly spliced. The operation is then repeated with the other broken end. Pipe ‘‘Tree’’ for Young Climbers HE play in- stinct in chil- dren usually de- mands satisfac- tion in climbing one thing or an- other. A_ tree naturally is the most tempting challenge. As a substitute, for back yards where no trees grow, a California manu- facturer has de- vised the next best thing, which he calls a “climb- ing-tree.” Itisa framework of joined pipes formed with a central “‘trunk”’ and a series of “branches,” one above the other. There is little danger of a fall, or torn dresses, or bruises. Guard rails protect the ends of the “branches.” **T HAVE COMPLETED six ship models de- scribed in the PopuLAR SCIENCE MonTHLY Home Workshop. Four were Barbary pirate ships which I sold for an average of $45 each, and two were Spanish galleons, sold for $125 each.—W. J. HazLEwoop, To.LeEpo, Ouio.

Page 42

48 One man can operate three or more of these machines with very little effort A Clock That Acts as Secretary OR the man with many appointments and business calls to remember, a new type of clock for the desk provides an electric secretary always on the job. The rim of the dial is slotted for every quarter hour of the day, and a metal clip inserted in the proper slot insures a buzzing re- minder. A slip of paper bearing a memo- randum is attached to the clip when the alarm is set. Automatic Die Caster for Small Lead Parts How Much Do You Know of the World You Live In? OU know more than the aver- age, if you can answer more than half of the following twelve questions selected from hundreds of queries sent in by readers of Poputar ScreNcE Montuty. The correct answers appear on page 165. 1. Where are there oil wells un- derneath the sea? 2. Where is the center of pop- ulation of the United States? 3. What place in the United States has the longest days? 4. What are the floating gar- dens of Mexico? 5. How fast does the Gulf Stream flow? 6. Which continent has been least explored? 7. What is the Tower of Lon- don? 8. Where are messages sent by drumbeats? 9. Where are the speaking statues? 10. Where do people eat earth? 11. Where did kings wear feather cloaks that took a hun- dred years to make? 12. Where do ferns grow as tall . as trees? POPULAR SCIENCE MONTHLY N THE remarkable new automatic die casting machine pictured at the left, invented by R. H. Williams, of Detroit, wheels and gears are substituted for the timing needed to produce die castings such as storage battery grids and other small lead articles. Molten lead flows through a valve controlled by the timing mechanism. After the die is filled it is kept closed long enough for the lead to harden, and then opened. The battery grid is ejected from the die and carried out of the machine by a moving belt which stacks the grids in an or- derly pile. The timing con- trol then closes the die and the operation is repeated as long as pig lead is fed into the melting tank. Because no attention is required except the feeding of the lead, it is possible for one operator to take care of several machines. The machine is geared to make two hundred operations an hour. Pocket Lamp Held Like Cigar ELD easily in the mouth and switched off and on by the lips, this handy little pocket lamp leaves both hands free to work with. The battery for it is carried in a vest pocket. It is especially prac- tical in fine work for which a direct beam is needed, or for work which must be done in darkened rooms, such as photographic de- veloping. It was invented recent- ly in Germany. As a dark room lamp for photographic work Left, wal- nuts branded for identifica- tion. Above, the new stamping machine Brands 2,000 Walnuts a Minute " Begee wigaaiaene grows more than ninety- eight percent of all the walnuts grown in the United States, and the prob- lem of branding these millions of nuts to identify them from all others has long perplexed the nut growers. Recently the machine above was selected from 900 de- vices submitted in competition. The nuts are stamped with printer’s ink as they pass under the sponge rubber dies on a revolving cylinder. The cups on the cvlinder are large enough to hold all sizes of nuts. The stamps are inked with each revolution from a roller above the cylin- der. Sponge rubber dies accommodate themselves to the size of the nut, and the * stamping pressure is light enough to make a legible imprint without cracking the shell. It prints 2,000 nuts a minute. A NEW SOURCE of paper is shortly to be exploited in Northern India—bamboo. Extensive tests have shown the feasi- bility of converting bamboo into paper pulp by treatment first with sulphate of soda, giving unbleached pulp; then with bleaching powder, producing finished pulp. Mechanical Arm Unloads Logs from Cars O UNLOAD logs from railway cars into the mill pond, the ingenious steam-operated machine below was in- vented by M. F. Crawford, of Natalbany, La., where it was recently placed into service by a This unloader consists of a cylinder extending ten feet from the engine on a track parallel to the loaded car. The hook at the end of the extension rolls the log forward off the load at asingle stroke. Louisiana lum- ber company. The work of un- loading the heavy logs from the cars which brought them from the jumber camps into the mill pond for- merly was done by men equipped with prying hooks. By that method, there was always a constant danger of crushing or maiming. Extension hook pushing the logs off a car into the mill pond

Page 43

Qdd‘* Watch”’ Tells Time by Stars HILE the fact that the stars ‘YY apparently revolve about the North Star is known to nearly everyone, itremained for Frederick C. Meacham, of Garden City, N. Y., to work out a simple way to link up this “motion” with the hours of our time system. As shown in the illustration above, Meacham’s device consists of a thin disk in the center of which are pivoted two pointers. On the inner circle of the disk are printed the months and days and on the edge the hours of the clock. To tell time by the stars, one of the levers is set to the day of the month. Then, with this lever pointing directly at the ground, the disk is held a few inches from the eye in such a way that the North Star can be seen through the cen- ter. Then the other pointer is moved around so that it apparently touches the two stars that form the side of the bowl of the dipper opposite the handle. If the observation is carefully made, the pointer will indicate the exact time. A RADIUM-BEARING ore vein of consider- able size and value was reported discov- ered recently near the old Tuya-Muyun mines in Turkestan, Asiatic Russia. POPULAR SCIENCE MONTHLY Yardmaster Directs Switchmen by Radio 49 ROM. his watch- — tower the rail- — road yardmaster is lord of all he sur- veys. Not only can he see the full stretches of his king- dom, but through a new application of radio he can now direct men in its furthest domains with his own voice. With the comple- tion of its new yards, the Illinois Central Railroad at Chicago installed a radio microphone in the yardmaster’s tower. An amplify- ing system of eleven loudspeaker units and as many micro- phones is scattered about in the yards. Instead of sending orders to switchmen by means of runners, the yardmaster now sits at his desk and gives them over the radio. His voice as he issues orders is amplified many times over, and his directions reach the ears of the men loud and clear. It’s Hammer and Wedge in One ANDY for opening boxes and other uses around the house is the combi- nation hammer and wedge above. The shape of the claws makes it possible to lift a nail straight up. Its construction— solid steel from end to end—gives strength necessary for hard prying strains. Motorcycle Driven by Airplane Propeller Blade NOTHER variant of the airplane- propeller-driven vehicle, invented by John Stout, of Zion City, IIl., is pictured below. The engine, though small, spins the propeller at a rate that makes fifty miles an hour an easy speed for this motorcyclist to attain. The simple and open construction of the chassis reduces wind resist- ance toa minimum. Details of the construction are shown clearly in the illustration, and need no explaining. For speed on land as well as in the air, the airplane propeller is finding many uses. Here’s the latest Switchman, above, receiving through loudspeaker orders from yardmaster, at right Chemists Wear Glass Uniforms LATE glass overalls, masks and gloves have been designed to protect chem- ical workers who handle acids, powders, and other corrosive and inflammable materials. Binding together the material with copper wire insures flexibility. Know Your Car ESTS have shown that bal- loon tires as they are now made will give as good service as the high pressure cord tires, but long mileage can be obtained only if care is taken to keep them up to the proper pressure. All euto tires gradually lose the air that is pumped into them. The rate of leakage usually is faster in hot weather than in cold. Most motorists are in the habit of pump- ing their tires up to the recommend- ed pressure and then letting them alone until they see the tire getting flat. A better plan is to pump up the tires at regular intervals of once a week in summer and once every two weeks in winter. Put in a few more pounds than recommended, so that by the end of the period the tires will have dropped only a pound or two below the proper pressure. Watch these points: 1. Pump your tires at regular intervals. 2. Always pump in three or four pounds more than recom- mended. 3. Make sure that your front wheels line-up properly. 4. Use your brakes as little as possible. 5. Keep away from curbstones.

Page 44

Raising What the Germans Scuttled The German warship Hindenburg was brought to the surface recently from the bed of Scapa Flow, Scotland. The photo below shows huge pumps drawing the water from the hull. The ship was scuttled by its own crew six years ago, after the surrender of the German fleet POPULAR SCIENCE MONTHLY & ee Patience on a Pedestal Anyone can produce a masterpiece of crafts- manship if he puts his soul and patience into it, thinks Homer D. Notes- tine, of Lewistown, O. He is shown above with the pedestal he made by piecing together some 2400 bits of oak, ash, walnut and wild cherry 4 wr ~ ™.. s { She Moves in Artistic Circles = ay ae , m a 1 he December, 193 Artists occasionally do have practical ideas, as this English girl painter proved. She had her bungalow studio constructed to revolve in a circle, so she would always have the best light The U ncommon Enter—the Human Airplane Wings and tail attached to the body of the daring diver at the right enable him to soar like a bird over the heads of other swimmers. The dive was a spectacular feature of a Gymkhana held by the Jersey Swimming Club Py The Newest Ball Game A huge ball, painted half red and half green, floats in the water. Splashing around it, seizing the handholds that cover it, are two teams, each team striving to raise its own colored half of the ball above the water. This, as pictured below, is one of the latest aquatic sports from California A Whale of a Surf Board No commonplace board for this dare-devil aquaplanist, above! He is balanced pre- cariously on a 45-ton whale which, caught off Los Angeles, is being towed in to port

Page 45

POPULAR SCIENCE MONTHLY What’s in One Warship’s Magazine Grim messengers of death, stacked row on row, waiting for the ‘‘next war’’—the shells loaded on the barge below were the ammunition of one single warship, the U.S.S. Utah. They have been removed pend- ing alterations on the ship in progress at the Charlestown Navy Yard Going Ford One Better By knocking down a new Ford and cutting it up in all directions, an ingenious service station man of Knoxville, Tenn., reconstructed this handy service car. It slips through traffic jams like an eel among fish Run of lhings Mirrors Warn Motorists Here’s a traffic cop whose job is a sinecure. The mirrors below are installed where three roads intersect at Ashford, England. An approaching driver can tell by look- ing in them if the crossroads are clear Built in Half a Week The house above was built in three and one half Caught in the Act days, in merry England. Forty-two men built it, When the walls of a hotel at Long Beach, not a carpenter among them—most of them were N.Y.,collapsed the other day,a photographer clerks. This stunt was a demonstration to show on the spot whipped out his camera. The how quickly and easily this new type of concrete result was the extraordinary photo above, house could be put up, even by amateur builders showing the wall at the moment it crashed It’s a Paper Mill and Makes Real Paper Actual paper four inches wide comes off the last rollers of the miniature A mechanic spent twelve years making this model, which measures about paper mill above, made in France. Students in France often take special ten feet in length and received a medal at the Lyons exposition. Each of courses in paper manufacturing, which is a chief industry of the country. its tiny parts works as smoothly as those on a machine of reguler size

Page 46

52 POPULAR SCIENCE MONTHLY Famous Oarsman Invents New Single Shell NEW. type of rowing shell in ing seat is made sta- tionary, the foot rests and oarlocks sliding instead, has just been designed byC.S. Titus,of New York City, once a champion oarsman. Titus contends that the sliding of the seat shifts the full weight of the rower’s body so as to interrupt the smooth progress of the shell. With slid- ing foot rests and oarlocks, on the other hand, only the Cc. S. Titus, former rowing champion, exhibiting his new shell weight of the row- equipped with ‘sliding foot rests and oarlocks. The seat is stationary ers legs is shifted. New Movie Camera Records Sea Wonders PICTORIAL record of under-sea life off the Florida coast is being made by Dr. Paul Bartsch, curator of mollusks at the National Museum at Washington, by means of a new motion picture camera constructed under his direction. It is water-tight, and can be regulated as to speed, or focus, as readily as on land. The tripod holds it steady against the action of the water. Olive oil and a diver’s helmet are all that Dr. Bartsch needs in his work at the bottom of the sea. Hitherto, pictures of this kind had to be obtained through elaborately furnished diving bells or glass- windowed chambers which were let down from chartered ships. This method proved too costly for extensive work. With his body greased, and air supplied to his helmet from pumps above, Dr. Bartsch expects to be able to work five hours under water at a stretch, at depths rang- ing from ten to thirty-five feet. Dr. Paul Bartsch, of the National Museum, loading his new submarine movie camera Detects Factory Shocks N ENORMOUS seismograph recent- ly constructed by Dr. E. Rothe at Strassburg, now part of France, is so sensi- tive that it records quivers in the earth caused by machinery in factories more than a mile away. The instrument, which weighs nineteen tons, magnifies earth vibrations two thousand times. Auto Awnings Dividers and Pencil Combined the Latest HE combined dividers and pencil DJUSTABLE awn- shown above make it possible for the ings that protect user to take his results and record them in passengers from sun and a note book immediately without remov- rain are a novelty in ing the instrument from his hand. Each automobile accessories. leg of the dividers carries clips for sup- Rigid construction stops porting a pencil, while one of the legs car-__ rattling or flapping, the ries a larger clip to receive the forefinger maker claims. They of the user. The device is the invention of | swing with the doors and F. L. Sorensen, of Fairmont, Minn. are attached quickly. which the usual slid- A closed car equipped with the new removable awnings December, 1, | December Cycle Side Car Made froma Wrecked Toy Auto AKE the chassis of that wrecked toy automobile you bought for your youngster last Christmas, attach a spring or two, and a cycle wheel, then fasten it tog bicycle, and you have an ingenious side ear vehicle, says William Sill, of Cleveland, who made the one illustrated here for his two little girls. Ballr The bicycle requires some remodeling in order to accommodate the side car, and there’s quite a bit of work to it; but, take D* it from Dorothy and Ruth, above, it’s pe worth it! eter Pp novelt; Today’s Winds Could Run Our nhs Factories 400 Years small ] T ANY one instant, the enormous | neath, energy stored in the winds of the correc! world is equal to a hundred million million horsepower hours, enough to run all the C factories of the United States for more A than 400 years, if it could be harnessed ‘'G and drawn upon as needed. Today this vast power is almost wholly unused by | report men. Wh These astonishing calculations recently | gravel were made by Edgar W. Woolard and | trodu announced by the U.S. Weather Bureau. | same: The power of the winds, Mr. Woolard } bread says, is being used up continually by the | coner friction of the masses of air against each } stron; other and against the surface of the earth, | lighte These losses, he calculates, are about one thirtieth of the total power each hour. If the supply of energy were not renewed, Pla naturally the wind would cease to blow. It is renewed by the heat and light of the 0 sun, absorbed by the atmosphere. C The winds are described as a great heat engine, absorbing solar power and using it reac at a rate of some three million million lie horsepower. If some practical wind motor andi could be devised to use even one hundredth trafh of one percent of the enormous wind and energy, it would give us enough power to a replace all the engines and dynamos in the world. Cen

Page 47

r US on ion tor ith ind Ballroom ‘‘Clock’’ Beats Time for Dancers ANCERS and orchestra can keep perfect time with the dance speedom- eter pictured above, a new ballroom novelty consisting of two dials for count- ing the beats and indicating the correct thythm. As the pendulum swings, a small hammer taps the little drum under- neath, so the musicians can follow the correct time by eve as well as by ear. A Concrete That’s Like Coral “(NASSING” concrete to give it added lightness is a novel idea recently reported from Sweden. While the concrete, a mixture of sand, gravel and cement, is still soft, gas is in- troduced into the mixture. This has the same effect on the concrete as yeast has on bread, filling it with small holes. The concrete so produced, it is said, is just as strong as the ordinary product, but much lighter, requiring less steel to support it. POPULAR SCIENCE MONTHLY 53 Piece of Cork Inflates Life Belt Automatically LIFE-SAVING belt that goes into action automatically when the swim- mer gets into trouble is a new invention recently reported from Austria—the creation of two Viennese mechanics. The belt remains deflated until the actual emergency arises, when it inflates, bring- ing the person to the surface, it is said, within ten seconds. This is accomplished by means of a cork attached to a rod which governs a valve. When the swimmer sinks, the cork is drawn upward to the surface, lift- ing the valve. Air is thus released from the container, where it is compressed, into the rubber belt. The device is light in weight and is de- signed so as not to interfere with freedom of movement in swimming. Lamp Exposes Counterfeits ICTURED above is the remarkable quartz lamp recently invented in Germany, the powerful ultra-violet rays of which are said to reveal fakes and forgeries in paper and fabric. The light exposes differences of colér and texture, it is said, and is being used, as shown above, particularly for the detection of forgeries and counterfeits. Planes Need Traffic Cops at Berlin ONGESTION of the air at the Berlin terminus of European air lines has reached such a stage that it is necessary to station men to direct traffic at the landing and take-off points. These aerial traffic cops are equipped with standards and flags to signal and direct the planes and to prevent accidents. The photograph at the left, taken at the Central Air Port in Berlin, shows an officer holding up other traffic to give a plane a clear right of way for departure. The two other cops are stationed at a starting flag giving the signal for a land- ing. Though operating now on a gigantic scale, the Berlin air port amazes visitors with the clocklike precision with which the arrivals and departures are managed. Airplanes are constantly landing or de- parting—for Paris, for Poland, for the South. Hours are rigidly fixed and ‘strictly adhered to. The place hums like abeehive, with all the pleasant excitement and bustle of a great railroad terminal. Below: Traffic cop at the Central Air Port near Berlin, clearing the way for a take- off. Right: Cops directing a landing The life belt inflated. Ordinarily it is worn collapsed, permitting freedom of movement Slot Machine Sells Clean Towels ROPPING a coin in the slot and receiving a towel is the newest adaptation, recently patented, of the familiar vending machine. The coin re- leases the shaft about which the towel is rolled, and a clean length may be with- drawn. The shaft is normally held in position by a counterweighted locking lever, pre- venting the withdrawal of a towel. When a coin is inserted through the usual slot, it falls into a box on the locking lever, which is thereby rocked to release the roller shaft. A catch prevents the roller from turning more than the length of the towel until a new coin has been inserted. Pipe Joints Made of Rubber NE of the most remarkable recent applications of rubber is the manu- facture in England of flexible pipe joints. These rubber joints are being used for pipes carrying water, oil, gas, and so on, their chemically resistant properties giving them, it is said, special advantages. The pipes are joined by rubber rings, making a tight, flexible joint. j With clocklike precision, a new kind of traffic officer directs arrivals and depar- tures at this great German air station. We may soon see similar stations in America, with the launch- ing of our great new com- mercial aviation program

Page 48

Dr. W. W. Coblentz of the Bureau of Standards showing the new glass screen Wall Paper Removed As Easily As Peeling a Banana EVERAL seasons’ accumulation of wall paper layers in an average-size room peel off like magic in the space of two and one half hours, according to the makers of the wall paper removing machine shown in operation at the right. It works by steam. A steel plate is pressed against the paper, and steam penetrates the layers through its perfo- rated surface, loosening the paper so that it can be scraped off with a knife. At the same time the fine needle-spray of steam is said to eliminate dust and kill germs. The process leaves the plaster clean for immediate repapering. The steam is generated in a steel boiler and raised to an eight-pound pressure with kerosene as fuel, the kerosene being kept in a copper tank said to be proof against fire or explosion. For ceiling work, a special device fits around the waist and over the shoulder of the operator to save him from back and shoulder strain. Vanity Case Banks Milady’s Pennies N THE lid of the vanity case at the left is the usual square mirror, and the compart- ment for powder and puff is also of conventional design. But the maker has ingeniously found room for a small coin bank, shaped so it will fold into the limited amount of space—thus loading one more duty on this already overworked article. Powder puff, rouge, mir- ror, and small change Clock Operates Electric Switch CLOCK-DRIVEN switch to control electric current, shutting it off or turning it on at any predetermined time, is the invention of H. F. Schoenman, president of an Eastern firm of manufac- turing jewelers. The switch contains a mercury-filled tube actuated by a. clock. Rocking the tube causes the mercury to flow to one end and close the circuit. POPULAR SCIENCE MONTHLY New Glass Protects Movie Actors’ Eyes OVIE actors and actresses need no longer fear “ Kleig eyes” from the powerful studio lights, it is reported. Bureau of Standards experts have de- veloped a remarkable new glass said to protect the eyes from harmful ultra- violet rays, such as are radiated from the movie studio arc lamps. Dr. W. W. Coblentz of the Bureau is shown at the left with the new glass screen, which will shade the lights. The glass contains cerium oxide, an element said to absorb the harmful rays without af- fecting the power of the light. In order to make use of the new screen, a slight change will have to be made in the light itself. The carbon electrodes in the arc lamp will have to be white or yellow flame producers, and the photographic films will have to be sensitized to the yellow and red rays. Steam spray penetrating the thick layers loosens the wall paper from the plaster Hort sprinGs that exist in great numbers under the city of Budapest, Hungary, are being used for the first time, experi- mentally, to heat the city’s buildings. Canoeists Use Airplane Propeller and Pontoons NCE it was a canoe, but since it acquired a motorcycle engine, an airplane propeller and a_ half-dozen pontoons, the odd-looking craft below has had a tough time trying to identify itself. However, it is meant “for speed only,” its ingenious inventors, QO. L. Swanson and Herman Linne- mann, of Peoria, Ill., claiming a speed of fifty miles an hour in their novel craft. The six pon- toons, three on each side, are de- signed to keep the boat from turning over on sharp turns or in rough water. Blue Coloring Matter Made from Old Pots and Pans LD iron utensils have been of little use except as junk until a new method of using them to make a blye pigment of high commercial value was discovered in England. The old iron is thrown into a tank of sulphuric acid, which converts it into sulphate of iron after treatment in ap. other tank. The final solution results ing blue pigment, which is used to make newsprint paper white and ink an intense black. The photograph above shows the iron in one stage of its conversion, when it is turned into wonderfully formed, yellow colored crystals of prussiate of potash, which adhere to strings dipped in the tank. Incubates 500,000 Eggs at Once HREE million baby chicks a year is the output of a California hatchery, where the incubators have a capacity of 500,000 eggs, thirty tons of them, ata time. Electricity is used throughout, to turn the eggs automatically six times a day and to maintain an even temperature of 103 degrees. After twenty-one days, electrically operated gears open the long line of incubator doors so that the new chicks may have light and air. With its lightness and the shallowness of its draft, the canoe can navigate rivers not practical for the motor boat, its in- ventors say. The canoe measures sixteen feet, and the motor has 25 horsepower. The two inventors in their ingenious craft. Pontoons make short turns possible Sl

Page 49

ice ar is ery, y of at a L, to es a ture ays, long new s of vers 3 in- teen wer. December, 1926 POPULAR SCIENCE MONTHLY 55 Spiral Garage May Solve Our Parking Problem ORELIEVE the congestion caused by parked automobiles that has become a, serious problem in large cities, Samuel C. Lancaster and C. O. Hjermstad, of hicago, have worked out a novel way to build a garage that could conveniently park a tremendous number of cars. of building the floors level and and then using elevators to lift the cars from the street to the various floors, the new garage would have a floor in a con- tinuous spiral from the street to the top floor. The cars would climb around and around the spiral under their own power and coast down. A ten-story garage built according to their plans, the inventors say, would house over 500 cars if erected on a plot 115 feet square. This would be equivalent to the king space along both sides of a city street sixteen blocks long. Above: Hasp and escutcheon plate of the new lock. Below: Inside door-bolting device A NEW ELECTRIC prospecting instrument is being used by the Ontario Department of Mines to indicate the presence of gold deposits—not so much to locate new veins, however, as to survey known areas. Plan of the proposed spiral garage, showing how the double driveway would allow free and easy movement of cars, on their own power going up and coasting down. Such a garage, it is said, could be emptied in seventeen minutes, as compared with five hours for the lift type Locks That Foil the House Thief WO new styles of locks said to be virtually burglar proof have been designed recently by a New York in- ventor. The hasp, as shown in the upper illustration at the left, has a flange that is mortised into the door jamb so that it would be impossible to rip out this plate without practically destroying the door. The escutcheon plate of the lock is de- signed with a raised ring of metal sur- rounding the cylinder, as indicated with the pencil, to prevent the using of a cold chisel to break off the front plate. The inside of the lock is cast with protuber- ances that engage with the cylinder and prevent its forcible turning. The same principles are applied to the inside door bolt in the lower pictures. EaGs ARE Now dipped, for preservation, in an oil bath maintained at a tempera- ture of 235 degrees F. Old Trolley Car Now a Lunch Wagon my BAT becomes of old trolley cars? Are they rebuilt as the busses that in many places are displacing them, or simply scrapped as junk? New Jersey, at Scrapped when the busses came, this old trolley car is now serving hungry Jerseyites as a convenient roadside lunch wagon least, finds a real use for them by convert- ing them into lunch wagons. Several are now placed along the main shore highway leading to the New Jersey coast resorts. Concrete blocks support the body at several points. A counter with stools in front of it and the usual cooking apparatus fit snugly into the space available, and astring of elec- tric lights placed above the windows attracts attention. Comfortable and clean, the cars do a rushing business during summer. MAIL BAGs ARE dropped 5,000 feet from airplanes without damage, it is reported, by a new method devised for European airways. The device is secret, but is said to be a parachute operated by clockwork. Wayside stations are planned for receiv- ing mail delivered in this new way. It Lifts Heavy Stone Blocks ESIGNED as f a labor saving device for building industries by the U. S. Bureau of Standards, this stone- lifting con- trivance does not need a double _ grip; it is plugged into a small hole in the surface of the stone, where it catches with a grip sufficient to hold the block firmly while it is be- ing trans- ferred from floor to truck or vice versa. Lifting heavy block with the new hook Device Cleans Grain by Vacuum ACUUM-CLEANING grain to re- move smut and light dockage is the job performed by the “ Bates aspirator,” the invention of E. N. Bates, market specialist of the Department of Agricul- ture. Grain thrown from the thresher elevator is spread in a flowing stream down the sides of a low flattened cone, while a suction from above draws a cur- rent of air upward through the thin layer of grain, cleaning out the lighter material.

Page 50

POPULAR SCIENCE MONTHLY Table Conceals White Enamel Tub The two pictures above show two views of the same piece of kitchen furniture—a combination table and laundry tub. Being white enameled, it can even be.used as a bathtub! The change is accomplished simply by turning the table on the side. It is supplied complete with floor drain assembly Filtered Coffee Must Seep Through Pad, Too Filtered coffee should not only retain all desir- able elements, but should lose all undesirable elements, say its advocates. The filter above carries out this idea. The coffee, after seeping through tiny holes, passes through a fiber pad which is said to hold back the harmful elements Scissors for Cut- ting Flowers It is possible to hold a flower below the point on the stem where it is to be cut, and snip the stem without the flower’s fall- ing to the floor, with the new scissors above. After the cutting edge does its work, the stem is grasped securely by the scissors Sugar Pours through Spout A screw cap, threaded to fit various shaped containers, keeps the sugar in this bowl (left) always covered, pro- tecting it from the assaults of wet spoons. The sugar pours out in a thin stream through a small spout. The device can also be used for certain varieties of uncooked cereal foods Why Not Make Your Own Ice? Six minutes is all it takes for this little machine at the right to make ice, ac- cording to its German in- ventor. A “‘cold mixture” made according to a given recipe surrounds a con- tainer holding water. The cover is screwed on, the apparatus is shaken slight- ly, and then let stand six minutes. At the left is a smaller size of the freezer nventors IDEAS Tha; A Kitchen Table Becomes a Laundry Ty} December, 19% Cores and Cuts at One Stroke Just a little pressure and the fruit corer above prepares an apple for serving at a moment’s notice. The sharp cutting edges separate the core and also cut the pulp into dainty slices lf Tender Steak from Tough Cuts A high school boy of Ada, Okla., invent- ed the ingenious device above for taking the toughness out of beef- steak and other leathery cuts. The steak is run be- tween the abraded rollers ¢ Potato Baker Folds Up Potatoes baked to a toothsome consistency by the device above are said to be uniformly *‘done,”’ dry and mealy. They are impaled on the eight prongs and hung over the fire or set in the oven. The handle regulates the prongs Dece

Page 51

1 19% Slices Butter into Small Squares A pound bar of butter is sliced neatly into individual portions, with the tool above. The butter is placed on the lower plate and ve the device is slid back, the two crossed A Holder for the te wires quartering it. Then the top part is Ice Pick pressed down, and the horizontal wires divide each quarter into ten equal parts The ice pick can always be kept at hand yet out of the reach of children, when a holder like that above is pro- vided forit. It keeps thepoint. sharp and free from rust, too Cream Whipper Fits in Fruit Jar The double beating ac- tion of the device at the right makes it possible to churn butter, beat eggs, or whip cream quickly and easily. It is small enough to be inserted in an ordinary fruit jar December, 1926 POPULAR SCIENCE MONTHLY re Hasing HOME [asks and a Pocket-Size Machine Makes Ice Clothes Basket Stands on Legs Folding legs on this wash basket save the laundress’ back in lifting and bend- ing, especially when she is hanging clothes on the line. The basket does not have to be set down to open the legs, a slight pull while holding it in the arms throwing them wide apart. Releasing catch refolds legs Boiled Egg Set Saves Fingers Direct transportation of the hot boiled egg from the kettle to the table without burning the fingers is possible with this new outfit (left). The frame- work holding the boiling eggs lifts out of the kettle and dries at once, all ready for the table It Opens Milk Bottles The cardboard cap on a milk bottle is removed easily by means 7 of a prong on the under side of this metal milk bottle cover (above) Cuts Potato into Ribbons This ingenious cutting tool (right), clamped to the kitchen table, will cut potatoes and other vegetables into long spiral ribbons for fancy cooking. In the picture, the po- tato is lying flat against a disk knife which slices it as it revolves 57 Glue Tube Seals Itself There is a tip of soft rubber on the mucilage tube above, and the paste flows through a vertical slit to be applied on the article. After the job is done, the tube is sealed by the hardening of the mucilage in the opening A Three-in-One Tool Three useful features are incorporated in the little tool above—a six-inch rule, a sharp edge for use as a letter opener, and, in one end, a small magnifying glass

Page 52

t i 4 ti \ ‘Tuning U Turn Adjustment Knobs Slowly Correct setting of the variable resistances that control the voltages supplied to your set is important if you want to obtain good tone N EARLY stages of the development of I B-battery eliminators the designing engineers were confronted with two important problems. One was to find a reliable way to rectify the alternating current into pulsating direct current; the other was to smooth out the pulsations in the direct current so that it could be used in the B-circuit of a radio receiver. Every engineer concentrated on these problems, and in the modern type of B-battery eliminator both have been solved almost completely. The direct current voltage delivered to the binding posts on the B-eliminator depends to a large extent on the rate at which current is drawn from the B-elimi- nator. The more current you draw the lower will be the voltage. In other words, if you have a receiver that draws very little current, the B-eliminator will de- liver this current at higher voltage than it would if the set took more current. ACUUM tubes, however, work best at the voltages recommended by the manufacturers, and if they are over- loaded the result will be a short life for the tubes. Your problem is to adjust your B-eliminator so that it will supply the required amount of current at exactly the right voltage. How to do this depends to a large extent on the receiver you have and the B-eliminator you buy. The smaller types of B-battery elimi- nators that are sold at a relatively low price are usually provided with one adjustment so that you can get the detec- tor voltage set at the proper value. The more expensive styles are fitted with two or more adjustment knobs designed to regulate the voltage delivered to each plus B binding post on the receiver. These adjustment knobs are connected to vari- able high resistances inside the eliminator ease. Turning the knob to increase the resistance lowers the voltage, and cutting down the resistance increases the voltage. At first glance it would seem that the simplest way to adjust the voltage would POPULAR SCIENCE MONTHLY December, 1926 p Your B-Eliminator By HarRRISON LEwIis How to Connect Regulator Tubes One can be used with almost any B-elimi- nator, but only the powerful instruments will work two in series to maintain 180 volts be to use a voltmeter just as you do with batteries. But that method won’t work because the current flowing through the voltmeter causes the reading to be much lower than it becomes the moment you disconnect the meter. The most practical method will be to determine the proper setting by judging the results. The best way to set the detector B-voltage is to tune-in some station that comes in rather weakly or turn down the volume control on a local station until the music is weak. Then increase or decrease the detector voltage until the signal becomes as loud and clear as possible. It is always best to have the voltage set as low as you can consistent with good volume. There ds less chance of hum with this setting, and owing to the nature of the detector circuit arrangement inside the B-eliminator, the lower you can keep this voltage the higher the voltages available on the amplifier circuits. 7. also is need for care in adjust- ing the amplifier voltages, because if you accidentally get them too high, the tubes will be overloaded and paralyzed within a short time. This is particularly trueof the radio-frequency amplifier tubes if no C-battery is used on these tubes. A popular method of controlling the volume of sound on the modern receiver is by means of a rheostat in the filament circuit of the radio-frequency amplifier tubes. Reducing the filament current through one or more of these tubes will cut down the volume without causing distortion. Difficulty occasionally is experienced with a volume control of this type when Tips on Adjustments That Will Save Overloading Your Tubes and Insure Good Tone a B-battery eliminator is used. Assumin that you have set the adjustment knob on the B-eliminator for the proper voltage on the radio-frequency amplifier tubes when they are turned up to get full vol. ume, there will be a sudden instead of a gradual falling off in volume when you turn the volume knob on the set. In other words, the volume control will be too critical. This peculiar effect is due to the fact that the tubes use less B-current with the lower setting of the volume knob, and consequently the voltage on the amplifier tubes rises. This higher voltage, in turn, still further reduces the volume with low filament temperatures. One way to cure this trouble if it both- ers you is to add a voltage regulator tube to the circuit. The connection is simple, Place an extra socket inside the receiver cabinet if there is room or mount it in g separate box near the eliminator. Con- nect the grid terminal of the socket to the plus B R F binding post (sometimes marked plus 90) and connect the diag- onally opposite filament terminal of the socket to the minus B binding post. Place a UX-874 voltage regulator tube in the socket and then adjust the knob that con- trols this voltage until there is a steady glow in the tube when the volume is turned on full. This tube will hold the voltage at 90 regardless of how much or little current is drawn in the circuit within rather wide limits. The drawing above on this page, shows how to connect up two voltage regu- lator tubes so that you can get a con- stant voltage of 180 for operating the new 171 type tube and 90 volts for the other’ amplifier circuit. This arrangement can be used only on the large and powerful types of B-eliminators, but you can use one regulator tube to advantage across the output of the smaller types of elimi- nators to hold the total voltage at 90 for use on sets that do not require more than this voltage. These regulator tubes are particularly useful if you live in a small town where the voltage of the electric light current is not steady. gigi: is one other point in the opera- tion of B-eliminators that should be watched carefully. Never turn on the eliminator until after you have turned on the switch that controls the current to light the vacuum tubes, and always turn off the eliminator before you turn off the set. This procedure avoids placing exces- sive electrical strains on the large-capacity condensers in the eliminator. If you use voltage regulator tubes, no special pre- cautions of this kind are needed, as the use of these tubes keeps the voltage con- stant whether the tubes in the receiver are turned on or off.

Page 53

December, 1926 If A Radio S RE you thinking of presenting a radio outfit to your family as a Christmas gift? Or do you con- template giving a set toa friend? In either case there are impor- tant things to consider before you make your purchase. " Tf your plans are not quite so ambitious and the Christmas money is to be invested in new equipment for your present ra- dio installation, such as a mod- ern loudspeaker, a new storage battery or a B-battery elimina- tor—here, also, are questions to be settled. Before purchasing any type of complete radio set you must get clearly in mind just what you want in the way of radio enter- tainment. In other words, you must decide what features are most important to you, and after that you can begin your search for a receiver that will give you the kind of service you want at the price you can afford to pay. The same considerations, of course, will apply if you are buying a set for someone else. Your decision will be influenced to a large extent by your location. If you live in New York City, for instance, you will have less use for a receiver designed par- ticularly to bring in distant stations. And this is also true if you live in any of the larger cities where there are a number of broadcasting stations. Whatever kind of set you buy, the local stations always can be received much better than those at distant points. No-matter where you are located, you will want accurate reproduction of music and speech. In fact, poor quality of repro- duction is enough to condemn any radio set regardless of any other good points about the instrument. In the early days of radio broadcasting, when all radio sets sounded like five- dollar phonographs, nobody worried about truthful reproduction. The mere wonder of hearing voices and music out of the air held everybody spellbound. It was enough if you could understand most of what the announcer had to say, and musical selections were distorted almost beyond recognition. A piano, for in- stance, generally sounded like a cross between a banjo and somebody pounding on a tin wash boiler. A modern radio receiver should reproduce a piano with sufficient realism to convey the illusion of the actual instrument to a person in the next room. HE number of tubes in a receiver has nothing to do with the tone quality. A five-tube set or even a three- tube set is just as likely to give correct tone quality as a receiver using seven or eight tubes, though the extra tubes may add to selectivity or distance range. There is just one way for the novice to POPULAR SCIENCE MONTHLY ou Plan to B Don’t stint on accessories, and insist on demonstration — Why the best 1s cheapest By Aurrep.P. LANE be sure of getting a radio receiver that has good tone quality, and that is to purchase a late model from one of the reliable manufacturers. By all means avoid bargain sales. In almost every case the radio receiver offered in a bargain sale is a discontinued model or the product of some manufac- turer who has gone into bankruptcy. In either case you are almost sure to get a set that is out of date or deficient in tone quality or some other vital feature. In fact no receiver of any make that was produced more than two years ago can equal in tone quality the better sets that are being made today. Naturally you will take into account the appearance of your radio receiver. You wiil want it to blend with the other furnishings in the room in which it is to be Watch These Points When You Buy a New Set 1. Choose a standard make. 2. Avoid bargain sales of obsolete sets. 3. Insist on a complete dem- onstration. 4. Make sure of good tone quality. 5. Buy high grade accesso- ries. Send for the list of radio receivers and accessories approved by the Popular Science Institute of Standards and use it as a guide in purchasing your new outfit. uy et for Christmas— installed. It will be up to you to decide, therefore, how much you want to pay for fine cabinet work. Most manufacturers are now turning out their re- ceivers in various styles of cabi- nets. If you buy the more ex- pensive models, in most cases you will be spending the extra money for looks, as the electrical units installed in the various grades of cabinets generally are of one single type. ARGAIN sales of radio sets usually stress the fact that the price includes a complete list of accessories. Often, however, the equipment sold with these bargain sets is of very low grade. “Bootleg” vacuum tubes, tin horn speaker and stale batteries may look all right to the novice radio fan, but they give such poor service that they actually prove more costly than good accessories. It will pay you to buy the best acces- sories that the market affords. That means high grade, standard vacuum tubes, a modern cone-type loudspeaker, a well-known make of storage battery fresh from the factory, and the larger sizes of dry cell B-batteries or an up-to-date B- battery eliminator. The cone-type loudspeakers are now being made by almost all of the leading manufacturers. Their growing popularity is a clear indication of the quality of present-day radio receivers, for a cone- type speaker will not give good results with a poor quality set. In fact when cone speakers were first introduced they came in for a lot of unjust abuse simply because they showed up the poor tone qualities of the receivers then in use. If vou want real quality, be sure to purchase a receiver designed to use the new type power amplifier tubes. The development of these new tubes is one of the outstanding advances in the radio art during the last year. EAR the set in actual operation be- fore you pay your money, and insist on having the demonstration made with several different types of loudspeakers so that you can decide which type is most pleasing to your ear. In listening, pay par- ticular attention to the low notes. Eliminators to take the place of B- batteries have now been perfected to such a degree that they will give as good re- sults as dry cell or storage B-batteries, and while they cost as much as four or five sets of B-batteries, the operating ex- pense after the B-eliminator is installed is very low. With one of these instruments on the job, you will not have to worry about run-down or noisy B-batteries. In buying a B-eliminator, see it demonstrated in actual use on the particular type of radio set it is to operate.

Page 54

Hints for Radio Beginners A Sharp Drill Saves Labor How to Improve Cutting Edge—What Causes Weak Signals Cutting Out the ‘“‘Twang”’ Putting rubber pads under the corners of a - fadio receiver to prevent vibrations from traveling up the table legs and on to the vacuum tubes—a constant cause of trouble ANY radio fans complain about trouble in drilling holes in the composition panels sold for ra- dio use. They say that drills dig in and jam and have a tendency to break through the other side of the panel, leav- ing a chipped and ugly-looking hole. The cause of most of this trouble lies in the fact that ordinary twist drills are designed to cut through steel, and when they are used on a softer material such as bakelite or hard rubber, the angle of the cutting point makes difficulties. To get best results in drilling these materials, you will find it desirable to stone the two cutting edges as shown in the photograph at the bottom of the page, so that the drill will have what is called a negative rake. In other words, the cutting edge of the drill will be shaped so that it will lose its tendency to dig into the material. A keen-edged drill stoned to a light negative rake will cut through bakelite or hard rubber with an ease that will surprise you. In drilling holes in radio panels, it is best to drill the hole with a. small-diameter drill and then follow with a drill of the size desired for the finished hole. Stoning the larger drill is particularly important in a case like this. fou will find that stoning the point of a drill also is advisable in drilling brass. It will eliminate the tendency to dig in. When Signals Become Weak EGINNERS in radio frequently are in doubt whether to blame their tubes or their batteries when the broadcasting becomes weak. Dry cell batteries of both the A and B type recover some of their strength when left unused for a day or two, whereas tubes that have become exhausted do not show this effect. Con- sequently, if you find that the radio set sounds almost normal for a few minutes just after you turn it on and then the music gradually grows weaker, you can be pretty sure that the batteries and not the tubes are to blame. Weak dry cell batteries should be re- POPULAR SCIENCE MONTHLY placed by new ones, but exhausted tubes can often be given a new lease on life by the reactivation process. A reactivated tube may not last as long as would a new tube, but the rejuvenation process gen- erally adds many hours to its life. And if it happens to burn out in the process, you can console yourself with the knowledge that the tube was probably too far gone to be brought back. Cushion It on Silence Pads | Ope your radio twang like a banjo string every time someone in the house slams a door or walks across the room? Most modern sets are built with cushion type sockets that eliminate this peculiarity. One way to get rid of it, if you have an older type of set, is to place rubber pads under each corner of the cabinet, as shown at the left. Two or three layers of rubber cut from an old inner tube will do the job. Shift your tubes around in the sockets, too, if the twanging is pronounced, because some tubes are more microphonic than others. The tube in the detector socket is the one that is responsible for most of the mierophonic noises. Handle Cone Speakers with Care HE cone type radio loudspeaker is, relatively speaking, a delicate piece of apparatus. You cannot bang it around and expect to get good results. In fact, one fall from the table to the floor is almost sure to ruin the paper cone and damage the electrical unit. However, this does not mean that a cone type loudspeaker needs special handling or is likely to get out of order easily. On the contrary, it may stand up to the hardest kind of work for years. If you want to get this kind of service out of your new cone speaker, put it where it > is not likely to be in- jured—on top of a book- case or near the back of a table that is placed against the wall. While damp air will not affect its tone qual- ities, water splashed on it will damage the paper, so keep the speaker, also, where rain cannot reach it. The amount of mois- ture in the air does cause the paper to expand and contract, but this ex- pansion and contraction is taken care of, in some makes of cone, by the method of mounting, and in others a thumb nut is used to clamp the wire from the speaker December, 19% A B C’s of Radio O ONE—not even the foremost radio engineer—can predict the results that will be obtained with any particular type of radio receiver in any given locality. Of course if your neighbor next door gets good reception, the chances are that you can expect equally good results. But if you live in a section where there are no radio sets, you’ll have to take a chance. All that a conscientious dealer can say about the distance getting qualities of even the finest radio set is, “If the reception of distant stations is possible in your neighbor- hood, you can depend on this set to get results.” On the other hand, the question of quality of reproduction can be settled definitely. If a receiver gives a lifelike imitation of the real thing in one locality, it will do the same in any other place. Before you buy a radio set, be sure to learn what kind of reception is possible in your neighborhood. If you live in an apartment, make sure you can put up an antenna if one is needed for the set you expect to buy. Changing the angle of the cutting edge of a drill to make it work more quickly and cleanly on such ma- terials as bakelite, hard rubber, brass and so on unit to the apex of the cone. Releas- ing this thumb nut and tightening it again relieves the strain caused by ex- pansion and contraction. It is desirable that the clamp nut be loosened and tightened again whenever there is a change in weather conditions. In other words, if the weather becomes damp after a long dry spell, or dry weather follows considerable rain and fog, the expansion or contraction of the paper should be compensated for by this ad- justment. Tune Back and Forth HEN youare trying to tune-in as accurately as possible to a certain sta- tion, you will find a little stunt used by professional photographers a great help. They always focus a camera by turning the focusing knob back and forth be- yond the correct point, less and less each time, until the motion finally stops at exactly the right point. Applied to radio, this means that you must move the dial or control back and forth until your ear tells just where to stop. A vernier dial will prove a help in fine tuning.

Page 55

December, 1926 POPULAR SCIENCE MONTHLY 61 CRadio in New Forms Loudspeaker Shaped Like Book In appearance this new type loudspeaker above (bottom view at right) looks just like a large book opened and supported at the correct angle for reading. The electrical unit is concealed underneath the curving dia- phragm of heavy paper “‘pages’”’ Emergency Trains Dispatched by Radio The Chicago, Milwaukee and St. Paul Railway is completing the installation of a short wave radio system that will serve for the reliable dispatching of trains during emergencies such as tornadoes, landslides, washouts and other disasters that inter- rupt. train-dispatching service over telephone and telegraph wires. Walter Dietze, of the company, is shown above testing it Illuminated Control Left: The celluloid dial and all the mechanism are mounted back of the panel with a special bezel frame let into the panel in the po- sition illustrated. The top button turns on a small electric bulb behind the dial Propeller Controls Voltage A unique feature of the latest French airplane radio set is the voltage control of the generator. No matter what the speed of the plane through the air, the springs controlling the propeller, as shown in photos at right, adjust it to turn the generator at constant speed >. ean oe ‘(iV = cr — ~® 5 etn OE DR mm OD MW Broadcast Studio Looks Like Radio Receiver Attachment Connects Phonograph to Radio Set Station WPAP at Palisades, N. J., has built a studio, above, mod- The plug shown in the illustration above is substituted for eled after a radio receiver. Round windows represent the dials. the detector tube in the radio set, and volume is controlled by The loudspeaker opening can be seen at one end of the building turning the control unit knob. No extra batteries are needed oO

Page 56

ENRY SPRATT jiggled the spark H lever up and down in a vain effort to make the top of the hill on high. “We shouldn’t have to shift into second on a grade like that,” he grumbled, as he pulled over to the side of the road and stopped the car. “T told you you were crazy to buy a secondhand car and start right out on a long tour with it,” replied Mrs. Spratt. “You might know some- thing would happen.” Henry. untangled his long frame from beneath the steering wheel. “Don’t start crabbing so soon,” he said. “I know what’s the matter now. The spark is no good because the con- tact breaker points need cleaning. Just watch me and you'll see how the job ought to be done.” “IT hope you're right, Henry,” sighed Mrs. Spratt. “Is that what’s been mak- ing the engine miss so much? I thought when the engine missed it was always the spark plugs needed cleaning. You told me that yourself.” “It depends on how it misses,” Henry asserted loftily. “If the miss is regular and keeps time with x the revolutions of the en- I gine, it’s always a spark plug; but if it skips at ran- dom you can’t blame any one spark plug. There’s only one pair of points that make contact for all the cylinders, and if they get rough the motor is likely to miss in any cylinder. “(XEE, here’s the trouble. I was right. The current has burned a hole in the stationary contact and all the metal out of the hole has piled up in a cone-shaped point on the other contact.” “What are you going to do about it?” questioned Mrs. Spratt. “You certainly can’t cut off that point and put it back in the hole where it belongs.” “Certainly not,” Henry admitted. “But I can use this file to get rid of the hump on one contact, and I can file off enough of the other to. get it smooth and flat again. The secret of this job is to get each contact rounded just a trifle so that when the two come together they'll touch in the middle instead of at the edge.” Henry proved he was right, for now the motor ran without a skip. They hummed along at good speed for several miles. Then, “My goodness!” exclaimed Mrs. Spratt. “My feet are burning up. Are you sure DER the motor isn’t on fire, Henry? What’s Wr POPULAR SCIENCE MONTHLY December, 1926 ong with Spratt’s Car? See If You Can Figure Out What Happened—Here’s a Chance to Test Your Auto Knowledge and Win a Prize “Tt is kind of warm,” agreed Henry. “T'll stop and sée what’s the matter.” As soon as the car came to a standstill a gentle hissing noise became audible and wisps of steam floated up from underneath the radiator. Henry shut the motor off. “The fan belt seems to be all right and the radiator isn’t leaking anywhere,” he Can You Help Him Find the Trouble? *M STUMPED,” said Henry Spratt despairingly, as he gazed at the motor of his stalled car under the feeble rays of the trouble light. Can you help him out? Read the accompanying story through to the end, then write to us telling just what you would do in similar circumstances. There’s a prize of $25 for the best letter. observed, puzzled. “I know there’s plenty of water in the radiator—Ah! Here’s the trouble! Look at that upper hose connection. See how the rubber is all swelled out? It’s getting rotten and I'll bet the inside layers of rubber have swelled, too, and closed up the passage. T’ll drain the radiator far enough to get the water level below where that bum hose is. Then I can take off the hose connection and cut out the extra rubber.” Again Henry proved he was right. He made the repair quickly. “T hope nothing else happens,” said Mrs. Spratt a bit more hopefully. “Knock on wood and trust in me,” Henry suggested. “I'll keep the old bus running unless the wheels fall off or— Confound it! She’s missing again! Now what’s the trouble? Acts like the mixture is too thick.” “Oh, dear!”’ wailed Mrs. Spratt. “You will never get it fixed now. It’s as dark as pitch.” “Humph!” growled Henry. “Don’t you think I can set the carburetor in the dark? Just watch me!” Henry soon had the hood up. As soon as he turned the knob to cut down the gas supply the idling motor picked up speed and ran quite steadily. “There you are! All set again,” he said as he settled his long frame behind the steering wheel, The car ran fairly well for several miles and then on a steep hill the motor refused to pull except in first speed. In fact they barely made the top of the hill even in first. HE missing, and weak, uneven running became. more pronounced until final- ly the motor quit firing completely and the car rolled to a standstill. “I didn’t stop it,” snapped Henry peevishly, in answer to the unspoken ques- tion inhiswife’seyes. “Itjust naturally died. Something must be wrong with the car- buretor. The gasoline is dripping out of it to beat the band. That means the float is on the blink or dirt has jammed the float valve. “There!” he exclaimed, after he had taken off the float bowl. “What did I tell vou? Look at all the dirt in the bottom of the bowl. After it’s cleaned out it ought to run as fine as silk.” Henry was doomed to disappointment, however, for although the motor started, it promptly stopped again to the accompani- ment of a gurgling, strangling noise. A second later gasoline started to flow out of the lower air intake of the carburetor in a stream. He groaned, grabbed a wrench and attacked the carburetor again.. The second cleaning did no more good than the first. “I’m stumped,” said Henry despair- ingly as he rested his elbows on the front fender and gazed at the motor under the feeble rays of the trouble light. What Would You Do? Porutar Science Montuty will pay $25.00 for the best letter explaining the nature of the trouble with Henry Spratt’s car and tell- ing him how to overcome his difficulties. Your letter will be judged solely on how accurately you size up the trouble and suggest the remedy. Mistakes in grammar or punctuation do not count. Address your letter: Aulo- mobile Editor, Popular Science Monthly, 250 Fourth Avenue, New York City. All letters must be received before January 15th, 1927.

Page 57

*S an even break in thrills when Father buys the Boy a Conn for Christmas! Dad gets his fun in seeing the Boy so happy. And as for Son, well, “Oh Boy!” is as near as he can put his feelings into words. Wise parents realize now that there is much more than fun for boys, and girls-too, in playing a Conn band or orchestra instru- ment. Besides developing musi- cal talent, it is a character-builder of proven worth, a way to social prestige, a help to success in any career. C. G. CONN, LTD., 1232 Conn Bldg., Elkhart, Ind. Please send free literature and details of free trial offer on ounty : Check if interested in organizing ) band, or ( ) orchestra. The Conn Band Service Department helps in organiz- ing bands and orchestras. Individuals and organiza- tions are invited to wrile for information; no obligation OH BOY! The increasing number of school and college bands and orchestras enlarges students’ opportunities and shows how educators value this training. Many of America’s leaders in business, statecraft, and .the professions have earned their education by cultivating their musical “bump.” Learning by new advanced methods makes playing a Conn fun from the start. Exclusive, easy-playing features of Conn instruments encourage young players, enable rapid progress. The Conn hy- draulic expansion process makes easier blowing, more beautiful tone, perfect scale and absolute uniformity in quality. Conns are used and endorsed by the foremost concert bands, symphony, opera and popular orchestras. Free Trial, Easy Payments. Try any Conn instrument in your own home. You can own it by small monthly pay- ments. Your Conn dealer will gladly show you the instrument which inter- ests you. Orsend the coupon now forfree literature and details of free trial offer. POPULAR SCIENCE MONTHLY OY ( Yristnas The New Ball- room Model \¥ Trombone pos- ¥ sesses many ex- clusive tages whichmake it the choice of trombonists’ in theforemost pop- ular orchestras. proved phone, used by leading popular stars has many features found in no other saxo- phone. The Conn C Melody is the beginner's best “Bete” The Conn Im- The New World Symphony trumpet is used and endorsed by famous trumpeters in the Sympho- ny orches- advan- Saxo- BAND INSTRUMENTS WORLD'S LARGEST MANUFACTURERS CULTIVATE YOUR MUSICAL ‘*B UM P’? WITH A CONN New York . Strand Theater Bldg. 7” 47th St. at Broadway Detroit . . 1431 Broadway Ave. New Orleans . 125 Carondolet St. Seattl 1613 Third Ave. Portlan Chicago. . d.. . 11th & Alder Sts, Oakland Atlanta... . 62 Mobile. . .. Boston . .. . 488 Boylston St. 62 E. Van Buren St. N. Broad St. 5 St. Emanuel St. Tacoma... . Baltimore . Factory Branch Stores San Francisco. . . 47 Kearny St. 2 2 eee « 531 16th Se. Kansas City . . 1011 McGee St, 1155 Broadway - 406 N. Howard St. © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Vancouver, B. C., 324 Hastings St. W. Conn National School of Music, resi- dence or correspondence instruction in all instruments—F. N. Innes, Di- rector, 62 E. Van Buren St., Chicago.

Page 58

Riss Usetu

POPULAR SCIENCE MONTHLY December, § | Ideas for Your Car Extra W heels Save Chains When Driving on Snowy Roads HILE many motorists seem will- ing to take a chance on driving without chains on wet roads, such protection is absolutely indispensable in the winter when the roads are covered with deep snow. Snow, however, often covers the road only in spots, and the chains wear rapidly when you strike the bare road surface. A most ingenious way to get around this difficulty is to fit an extra wheel to each of your regular rear wheels, as shown in Fig. 4. Four wooden blocks are bolted to the spokes, and the extra wheel is mounted on these blocks. The diameter of the extra wheel should be enough smaller than the wheel to which it is bolted so that the chain will not touch the ground when you strike surface that is not covered with snow. This arrangement has still another advantage in that the wide tread pre- sented by the double wheel effect keeps the car from sinking into the snow. Wooden Wedge Supports Spring HEN it becomes necessary to re- place the ordinary type of rear spring shackle bolts or bushings, you will find a wooden wedge extremely useful

(Fig. 3). It should be made of hard wood, as wide as possible without bt rege

sticking against the sides, and the wedge should be Ge

~ te be off a piece of wedge in place just tight BOLTS TO BE - TOGETHER each rod with an ordi- enough to take the weight off the bolts. It is un- Fig. 3. Use a hard- necessary to jack up the wood wedge like the f i. j one shown above when rame of the car. ven eee ooo shackle bolts. It will Rubber Band Stops Chafing LAT tires are often caused by the chafing of the tube against rough or rusty spots on the rim between the beads of the shoe. A regular fabric flap is sold to eliminate this trouble. If you have no flap, a good substitute is to cut a strip from an old inner tube and place it as shown below in Fig. 6. If you cut a piece out of the band and cement the ends together, the spring of the rubber will hold the band in place. Sewing the ends of the band holds the joint tight. It Holds the Flashlight EPAIRING or changing auto tires at night is a nuisance un- less you can ar- range to have suf- ficient light to see what you are do- ing. A standard

Fig. 6. A rubber band cut from an old inner tube prevents chafing

save jacking up frame

Fig. 4. An extra wheel bolted on in this way will prove useful in heavy snow and save unnecessary wear on the tire chains type of flashlight will give enough light, but if you are alone in the car it is inconvenient to have to hold the light and work at the same time. One way out of the difficulty is to bend up a simple wire stand as shown above in

Ten Dollars for an Idea! OSS H. ARNETT, of Medina, N. Y., wins the $10 prize this month for his suggestion of extra wheels to save chains in winter driv- ing (Fig. 4). Each month Popunar Scrence Montuty awards $10 in addition to regular space rates to the reader sending in the best idea for motorists. Other published contribu- tions will be paid for at usual rates.

Fig. 5. A jeweler’s saw will save time when a turnbuckle has reached the end of the adjust- ment. will easily cut through all sorts of brake rods

nary hacksaw. But a much simpler way is to: use a jeweler’s saw, as demonstrated in Fig. 5, and cut off the rods without disturbing the adjustment. The blade is tightened after it is passed through the opening in the turnbuckle. These blades A Running-Board Ice Carrier i ip most convenient place to carry & large chunk of ice in an autom is, of course, on the running board, butif you have ever tried it you know it B rather a difficult job to strap the ice in place satisfactorily. A few special studs mounted on the run- ning board will solve the problem. As shown in Fig. 7, they are made of %-inch carriage bolts with a hole drilled in the bolt to accommodate a 4- inch pin. When not in use the pins can be lifted out of the holes in the bolts and then stowed away in the automobile. REMOVA~ — RRQQAN " Ky SOS: S$ RUNNING BOARD Fig. 7. Studs like these will make it easy to carry ice On the running bo

Page 59

a 9g.

Page 60

Page 61

POPULAR SCIENCE MONTHLY

The Gold Standard of Radio Recay | ITH the FERGUSON Model Twelve you enjoy

Py ——e 4 oe N25 ESSE

”

<2 The Two Tuning Dials Light when the Receiver is in operation, Complete shielding gives this Receiver its Marked Selec- tivity. No Seasonal Models— Continually Develop- ing Refinements

© This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS, See page 6.

Page 62

A Christmas tip from the carpenter | sei at any fine piece of carpentry work. The finish comes largely from the skill of the carpenter, of course. But there’s something else. Look into his kit. You’ll see not only an adequate number of tools, but find them all fine tools, many carrying the Stanley name. Right there is a Christmas tip from the carpenter—a chest of Stanley Tools this year for some man or boy! A fine assortment of tools, and all good tools— the right set for repair work or the mak- ing of such things as book cases, dog houses, and other useful articles. The sturdy oak chest keeps the tools safe and handy. A Stanley Tool Chest is a complete gift. You will find Stanley Tool sets at a ‘wide range of prices and in a wide POPULAR SCIENCE MONTHLY Buy separately or in assortments No. 902 Tool Chest No. 907 Tool Chest variety of assortments—from No. 904 with 12 tools in a fine oak chest at $15, to No. 850 with 49 tools in a beautiful cabinet at $95. There are also assortments of the same Stanley Tools in cardboard dis- play boxes with simple directions from which the recipient can make his own chest. There are several of these ‘‘ Make Your Own Chest”’ assort- ments, at prices from $5 to $20. There’s a Stanley Tool Set to fit every pocket-book! Ask your hardware dealer to show you the line of Stanley Tools. And send for our Catalogue No. 34-E which de- scribes Stanley Tools both separately and in assortments. Address: The Stanley Works, New Britain, Conn. The best tools are the cheapest to use Ask your hardware dealer © STANLEY TOOLS ~ © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. a Me RE ae eR a EGE BR & Me Es

Page 63

eG a aa S VALS ae Le aie ta PaaS sy, ae ie Sr ee Spe ae chow Sa Le) es ele f ae ‘ Se Noth PERE eh Para Sty osc. is tine tan a eA ie a . : wees f s 7 pe ‘% oR ¥ mn tee. Pee : Shee, ies ene ‘ Soe : = sais _ - ae Ly at > : A: teva os te kes : : ait Vet, By : s Ay, ess t ~ be a : ea eit ee an : ~ , * m - Mi « J i % r ) ' % ‘ . ; : b te a Bes s ee : : : i t ) é : ‘ j : ‘ ‘ ‘ ; : ; ‘ oo ; . 3 s ‘ %, < { ., 3 : i 3 ‘ s P 4 : ; ' : | ‘ ee ¥ ’ + ms “ “ . el . ral . er ‘ <3 ‘ ’ *: i ‘ . , ‘ a , weet oS 0

Page 64

Page 65

POPULAR SCIENCE MONTHLY

Home Workshop Arthur Wakeling, Editor for Christmas By F. Crarxe Hucues SOY making is not difficult. It may | be done quite as well by women and girls as by men and boys. In very few of those who have never empted the work realize how simple js to construct attractive toys—toys at will give keen and lasting delight the children who receive them on tmas Day. put the only equipment necessary king many little toys such as are de seen in gaily decorated shop win- ys at this season of the year are a cop- et or bracket) saw, a jackknife, a mmer and a rule. hile other tools are sometimes needed d are always useful, they are not es- jtial. Do not, therefore, let the lack faa* ALL FOUR-LEGGED AN] MALS OF A SINGLE PIECE AS ATA, OR EE PIECES AS AT B ‘ALL BIRDS ARE BEST MADE OF ONE PIECE ASC FOOT OF TOY ANIMAL = , — Q z CARDBOARD ~———= A =< | —~ 3 © WOOD DISK LEG OF r 4 ; ANIMALIN] F AUF BUTTON 3 SS _ WELWIDTH EQUALS - "HALF OF HEIGHT — me he- and three-piece toys and several types "Of bases; how to cut forms with a coping saw of tools or a bench prevent you from beginning. Once you have fallen under the fascination of the work and dis- covered what fun there is in mak- ing toys, you will delight in adding new tools to your kit, and in a short time you will have a home workshop equipped for much more ambitious undertakings. That’s the joy of working with tools; you always have something to look for- ward to—something new to make, some new process to learn, some new materials to experiment with, some new tools to buy. The subject of tools cannot be dis- missed without mentioning a lathe. In- deed, for many of the spindle toys so much in vogue these days, a wood turn- ing lathe is the thing to use. Those who be- SECTION FROM if (Q)_smau DOWEL SPOOL g|@e” ry TIN ROOF fers aa Brain WHEEL TYPES OF TURNED WHEELS HUB FIG.4

pit mecenaniaeil =H WIRE AXLE

AXLE FIG.5 COTTER PIN Wheel construction at a glance—various hubs, decorations, and methods of mounting Well-designed wooden animal toys are more popular today than ever and making them is great fun come thoroughly interested in toy mak- ing will want to have a lathe sooner or later, but in the beginning it is usually possible to devise a substitute tool proc- ess or change the design of the toy so that turning is not required. In cutting out practically all of the toys illustrated in this article, an ordinary coping saw is sufficient. These saws may be purchased at hardware stores and are among the most inexpensive of tools. A supply of extra coping saw blades should be obtained; they, too, are cheap, so that the breaking of them, which is ° bound to happen now and then, is a small matter. The correct method of using a coping saw is illustrated in Fig. 2. Boards as heavy as 1 in. in thickness, if of white pine, basswood or any soft wood, may be sawed quite easily in this way. In Fig. 9 (page 101) are shown a num- ber of animal forms that were drawn es- pecially for wooden toys. These may be enlarged and used as patterns for toys of many types and sizes. ECIDE first to what size you wish to enlarge the toy. Draw on a piece of stiff paper or thin cardboard the same number of squares as appear over the out- line you intend to copy, but make the squares proportionately larger. In each square draw whatever appears on the cor- responding but much smaller square in Fig. 9, so that you will obtain an exact enlargement of the original drawing. “What a lot of drawing to do!” you may say. Well, then, don’t do it. Send for Home Workshop Blueprint No. 56, using the coupon on page 102. It con- tains every one of the designs in Fig. 9 drawn full size, ready for tracing directly on the wood. The elephant, for instance, is 71% in. long over all and 5% in. high; the pelican is 7 in. long and 5% in. high; the puppy dog is 4% by 5 in., and the others are of (Continued on page 98)

Page 66

68 POPULAR SCIENCE MONTHLY December, 19, Brush Lacquer and Your Car How a Brilliant, Durable Finish Can Be Given Any Automobile By Ratpu G. WarING “ ALL ready to start lacquering the car, Dan?” “You bet, Mr. Waring!” “Then get an inch and a half fitch brush, and a three-inch brush, as well. I'll meet you in the garage.” ; First I asked Dan to sprinkle the floor with the watering can. Although lac- quers do not absorb dust as readily as varnish and enamel, this precaution is worth while. Next we washed the brushes clean with lacquer thinner. The lacquer was stirred thoroughly for about five minutes to insure a perfect blend of pigment and lacquer body. Using the smaller of the brushes, I showed Dan how to cut across the top of the door, working from left and right to- wards the center of the roll edge with a fully loaded brush. This left a plump surface; it was brushed just enough to prevent having the lacquer sag. A newspaper was pushed quickly into place between the skirt of the body and the chassis frame to catch drips from the $-in. brush, which was used to flow the brushing lacquer across the panel, work- ing as on the roll. The lower edge of the last brush stroke was always wet and heavy enough to flow into the top of the next stroke. Dan and I found that it required con- _ siderable judgment to determine just when to stop brushing, and just how much material the brush should carry without having a sag. Luck was with us. Except for one small sag in the lower corner of the door, the surface looked fine. “We won’t worry about that,” I con- soled Dan, “for when it has dried, we can cut it out with water sandpaper. We'll make haste slowly, however, and Flowing lacquer on a door panel. The brush is kept well filled so that the bottom of one stroke will flow smoothly into the top of the next stroke. At right—Applying the first coat to the hood with gratifying results The lacquer was rubbed to a glass- like surface first with very fine sandpaper and a mild soap solution, then with a mix- ture of pumice, whiting and suds gain a little experience in our brush work as we go along. *“Let’s do the cowl next. I shall start here on the lower right side, brush in this panel complete, cross over the cowl with strokes parallel to the windshield and work only from the unfinished part to the fresh lacquered work, all with a rather short stroke.” HEN it came to the rear of the body, I started on the right side, next to the rear doorframe, and brushed in lines parallel to the fender, keeping the fresh work always at my right until I had advanced past the shoulder, then I found it was easiest to take a stroke of from 4 to 6 in. long, moving quickly from left to right, and a similar stroke one brush width lower down. The strokes faded out quickly where they met on the freshly lacquered shoulder. In this way I was able to flow out the lacquer just as I had on the door and a smooth job was the result. It seemed that the lacquer set too quickly to take a chance on using an up and down stroke. **Now, Dan, let’s set the hood over on this low sawhorse,” was my next sugges- tion. “That’s right, turn it so that the ventilating slits on the side have the edges pointing down. The face of the hood we will flow-coat with the three-inch brush as far as the hinge roll. The ventilated faces can best be worked with the inch and q half brush. Notice I start the stroke from the end of the slit toward the center working from both left and right, thereby avoiding the possibility of a sag at the corner. This done, Dan went ahead with the black work on the fenders and I did the many little. odd jobs of touching up around the windshield and_ radiator, frame, lamps and elsewhere. We gave the lacquer a five-hour drying period before applying the second coat, We found that this coat took hold of the first just enough to make the brushing a little harder, but not enough to be really troublesome. Unlike varnish and enamel, lacquer does not require to be sanded between coats. That is because lacquer coats dissolve one another partially and so bond perfectly. “We'll let this last coat dry over- night,” I told Dan—it was late any- way—‘‘and then we'll come here the first thing in the morning to water-sand and polish the car. You remember that in the experimental work the lacquer sanded better with a neutral soap solution in place of clear water, so I want you to cut up a small size bar of white soap and put the chips in a gallon jug full of cold water. In the morning it will be ready.” AN was waiting for me at the garage the next morning with his usual smile, He was inspecting critically the work we had done. “Tt’s pretty good in that eggshell fin- ish, just as it is,” he remarked. “Nevertheless, it will be a lot. hand- somer if we sweat over it for a few hours,” I assured him. “Pour out some of that soap solution into one of the shallow pans, and mix one third whiting with two thirds FF pumice stone to a soapy paste. Tear up a bunch of six-0 sandpaper of the wet- or-dry type into eighth sheets and then we will go to it. Have a pail of the soap solution handy to dip the paper in an another pail of clean water, with @ chamois and a sponge.” I demonstrated just how to hold the piece of sandpaper with one corner caught ° between the thumb and first finger, and the diagonally opposite corner between the little finger (Continued on page 9) BUY

Page 67

Greatest Toy” éled Scoop. Erector Enameled Dredce et. Curved Erector Girders. Giant Fly Wheel ied Red—A\l Exclusive Erector Featu (in No. 7 Set and — e models that this ector feature makes possible—Steamboats, Fire es, Hoisting Engines, Locomotives, etc. ‘arts In-Colors. (In all sets.)—Erector is | rom structural steel, nickel-plated and lac- Ree It is the pioneer construction toy with parts ed in colors, énameled and electrically baked ew Erector painted). An exclusive Erector feature. Sirips—Four Holes To The Inch, a POPULAR SCIENCE MONTHI.Y It tells you how to build steam shovels, dredges, automobiles, aeroplanes, engines—1000 work- ing models, many in colors, all from one marvelous construction set. ust think of the fun that is waiting for you when you read about these marvelous working models of the greatest engineering feats— trains, draw-bridges, steam shovels, concrete mixers, lighthouses, en- gines, motors, dynamos, railroad signals. And when you actually own a new Erector Set you'll get the thrill of your life when the motor starts to purr and the model which you have built with your own hands starts working—Oh, boy! how you will shout. Christmas or any other time will be the best day of your life when you get your Erector. The box is jammed full of fun. When you lift the lid and see all the wonderful parts, some in colors, your hands will itch to start building models right away. You'll play with Erector first. You'll be playing with Erector a year from now, too. But send for my book this very day. Then you can show Dad the pic- tures of these dandy Erector models. He will understand why boys call the new Erector, the world’s greatest toy. The Super Erector No. 7 The Set that Builds the Steam Shovel ee most popular Erector Set. This is the first set to con- tain the famous new Erector digger part, so that you$ can build the Steam Shovel illustrated above. Contains powerful Erector electric motor which makes your model run; new Erector boiler for building engines; also base plates, curved girders, perforated strips, die cast gears, beveled gears solid brass gears—473 parts, some in colors, enameled and electrically baked; builds 533 models shown in 76-page manual. Packed in a varnished, hard-wood box. Tell Dad now that \this Erector Set will make you happier than any other present. MY FREE OFFER When you send this coupon for my free book, you will also get an amazing present; the mysterious Erectorscope. It will mystify your friends, You've never seen anything like it. Just look through the Erector- scope! You won't be- lieve your eyes. Every- body will want to look THE A. C. GILBERT CO. 155 Blatchley Ave., New Haven, Conn. Please send me FREE my copy of the book, “1,000 Toys in 1,” and the mysterious Erectorscope. through it, too. Send Pe Re are, cheat, x wedi ori Wcaltba 0 eaten epacateaore tee the coupon now ani get the book and the Oe ee Erectorscope absolute- ‘oh 0 RES He ly free. BUY AN ERECTOR TODAY. AT ALL STORES WHERE TOYS ARE SHOWN © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 68

70 POPULAR SCIENCE MONTHLY utomatic Block Signal Syste; Fig. 2. trols the trains. model electric railways lies in oper- ating them in as realistic a manner as possible. The numerous factory built accessories are a great help in obtaining A LARGE part of the fascination of this effect. Crossing gates that close and ~ open as the train goes by, switches elec- trically controlled by buttons, and count- less other details can be added, piece by piece, until you have a marvelously com- plete system. Yet in spite of the amount of apparatus available, it is still impossible to buy a real automatic block signal system—one that actually will control the operation of two trains running on the same track and prevent a rear-end collision if one of the trains happens to be traveling at a greater speed than the other.° You can buy a thermostatically con- trolled train signal that will stop a single train for a few seconds and then allow it to proceed as the signal lights change from red to green, but this device will not stop a following train and prevent a collision. For the model railway owner who has only one locomotive it is satis- factory, but if you have two locomotives something more is needed. HAT you want is a real automatic block signal system and the con- struction of such a device is extremely simple. In fact the control device shown in the illustrations on this page was put together in one afternoon with no tools to work with other than a small wood saw, a pair of wire-cutting pliers, a gimlet, a screw driver and a soldering iron. And the soldering iron was not really necessary. The wiring that completed the instal- lation also was finished the same after- noon and after proper adjustment, the block signal system worked without a single failure for over six months until an exceptionally bad spell of damp weather last summer caused the wooden arm to swell and Fig. 1. With amazing realism, the model train comes to a full stop when it is about to overtake the train ahead, and later goes on by itself (At right) A ‘‘close-up”’ of the electromagnetic switch which con- The simplicity of construction can be noted at a glance Can You Work This Out? ERE’S a little problem for you. The automatic block signal system described in the accompanying article is intended for trains running only in one direction. Can you make a wiring diagram to show how the system may be connected up by means of electric switches so that it will work no matter in which direction the trains travel? Send in your solution before Decem- ber 31, 1926. The best solutions will be published and paid for at the rate of $5 each. ry and those who have watched it work have marveled at the sight of two trains running continuously around and around on the same track with no attention. When the faster train creeps up too close behind the other it is stopped in the block until the front train regains its lead. To the observer it is so realistic that it almost seems as if there must be a tiny engineer in the cab with his hand on the throttle. The heart of the automatic block signal system is the electromagnetic switch shown in Fig. 2. It has been made just as simple as possible so that you can build it with the tools found on almost necessitated a touch of the screw driver to loosen up It’s Easy to Add This Noa December, 1% Accessory to a Model - Electric Railway By James A. Baker every home workbench. You can im. prove the crude appearance and work. manship as much as time and facilities will permit as long as the basic principle is not changed. No alteration is necessary in the design or construction to allow for different types of current supply or voltage. It has been tested on both alternating and direct current at voltages from 6 to 21 and it works perfectly without even a change in the friction adjustment. That means, of course, that you can use it on any of the miniature electric train systems sold today. The electromagnetic switch consists, essentially, of two electric magnets placed on opposite sides of a movable wooden arm. On the arm are mounted metal contacts arranged to touch other con- tacts fastened to the wooden base. Fig. 3 shows a wiring diagram of the complete installation, which consists of the electromagnetic switch illustrated in Fig. 2, a signal tower for the red and green lights (Fig. 1), and the two track con tacts A and B (Figs. 3 and 4). Current is sent through the windings of the maghets by way of the contacts A and B, which are placed between the rails so that the collector rollers on the electric locomotive will bridge the gap between the third rail and either A or B. , ‘HE first job is the construction of the friction on the arm. It is still in operation, - Fig. 3. The lights are the electromagnetic switch, Study _ mounted in a signal Figs. 2 and 3 very carefully before you co wi lle start work. The base is made of a piece c B so thet the follow. Of board approximately 14 by 6 by 7 im i ing train will stop ex- 1t would be possible, of course, to make Can a actly in front of signal the whole control on a base measuring less than 2 by 3 in., but that would re uit quire extremely careful workmanship and be P Of O53 G2 gt pep there really is no need for a small swi | oa as this unit can (Continued on page 106) [ seen TRAINS TRAVEL ] IN THIS DIRECTION Turn to page 74 for A Bl ME cemesie the continuation = —_ [Toy oa the Home Workshop: Department. Amod 34 x7 | ine sla ofthe} angles with s plete Atas chang makit of po FOE. /

Page 69

POPULAR SCIENCE MONTHLY $2659 Cash Balance on easy terms Amodified standard billiard table,size 34x7 ft., with folding legs. Has genu- ine slate bed and all playing qualities t a ofthe professional size table,cushions, —M, b | h C h angles and balls being scaled down a e ZS vistmds with scientific precision. Comes com- lete with full playing equipment. | h B FE ira slight additional i e est ver changeable cushions may be had making it available for either carom ecpocker billiards, Have Dad Give You a Brunswick Home Billiard Table izes 24x 5 ft. and 3 x G ft., a * hed Bet "0 sate poe O game will provide more genuine |—to obtain one. For billiards is a sport pleasure, more fascinating enter- that you and everyone you know can N tainment, more lasting enjoyment than play and enjoy. And the more you play a Home Billiard table. It isthe greatest it the more interesting it becomes. It 1s gift of all—and lasts for years and splendid exercise, does you good both years. physically and mentally. Develops judg- Right now is the time—of all times ment, clear thinking and coolness. Brunswick Home Billiard Tables Are Inexpensive | A small initial deposit brings one to yourhome —the Playmate. And there are a number of | in time for Christmas. The balance may be paid _ other attractive models. | as you play. No extra space or special room is Write to day for full descriptions, prices and needed for the newest Brunswick Home Table _ easy terms. Fill out and mail the coupon NOW! | THE BRUNSWICK-BALKE-COLLENDER COMPANY Established 1845 Branches in All Principal Cities of the U. S. and Canada | oat a ee oe ee ee OO a a { THE BRUNSWICK-BALKE-COLLENDER COMPANY ; } Dept. H.1283, 623 S. Wabash Avenue, Chicago, Ill. : i Gentlemen: Please send me complete descriptions of your home billiard tables, together 3 ; with prices and terms, and oblige. y ) Drag a ae ers se a c f DY © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 70

72 POPULAR SCIENCE MONTHLY

‘Better Shop Method I How Expert Mechanics Save Sime and Labor <I S.

Machine Keys—How to Fit Them

Fitting a feather key. To do a really good job always calls for more than general experience and average care ACHINE keys couple together our M shafts, gears and pulleys, harness- ing our greatest servant, power. The standard shapes and kinds of keys are well-known to most mechanics, but many interesting points sometimes are overlooked in regard to them. Keys are fitted into milled or slotted grooves in the two parts to be fastened together; they may have plain or gib head ends, and they may be straight or tapered. Simple enough, it’s true, yet to be able to fit any one of them properly has always been a test of mechanical skill. When driven tightly home, a correctly seated key that is large enough to drive its load will also hold the gear or pulley in place on the shaft and prevent its slipping. A straight key generally is used in connection with one or more set screws and needs only to be a light tapping fit on each side, because these two faces are in frictional con- tact with the keyways. This type of key allows pulleys and gears to be disassembled with ease. Plain taper keys are fitted so as to have a light driving contact on both sides and a perfect fit on top and bottom. 1” dvgaetd a taper key is to be used in an inside position on a shaft, it is obvious that the keyway in the shaft must be cut twice the length of the key so that the key can be driven home from one side or the other of the pulley or gear. If the key is to be straight in this con- struction, it can be made to slide with a light frictional contact on the sides and, after it is in position, it Removing a key with a drift. machinists how troublesome a stubborn key can become can be held firmly with set screws. When the pulley or gear is close to a shoulder, it is not advisable to use a taper key un- less there is room for a head on the outside. Otherwise it would be very difficult to withdraw the key after it had been driven hard into its seat. Seldom can any provision be made in the design for withdrawing a taper key in this position other than using the gib key, but it is not always possible to use this type of head. Gib keys are generally used in end positions on shafts. Keys that must be driven tightly on account of unusually heavy loads should be preferably gib keys, as the head pro- vides a means of withdrawing them more easily when repairs have to be made. Where a taper key must be driven hard, it is good practice to give the ends a generous bevel and the fit should be emphasized on top and bottom rather than on the sides. The standard taper for keys is % in. a foot; in practice, however, it is not always possible to hold this taper true. Any variation from the standard may be com- pensated for by fitting the key to the taper which has been cut in the pulley or

It is well known by all Straight, Tapered and Woodruff Types—Ways to Remove Them If Badly Stuck—The Time-Saving Kinks of Old Bill By Jor V. Romic gear. In doing this, both ends of the key. way are calipered and the top of the key planed or filed down to correspond Another good way is to make a dummy key either of lead or hard wood. Whey the dummy is cut down somewhere near the right size, it may be driven into the key seat and driven out again. It will then serve as a model for making the key, re BROKEN ‘- GIB HEAD KEY

Spy BAR

KEY WU, BOLT REMOVING KEY WITH PROTECTIV NIPPERS AND PRY BAR ee ae

NIPPERS Za G iy N Gib key, key driver or drift, a safety cover, and a satisfactory method of removing a key In former years it was customary to forge gib keys or shape them out of rec. tangular stock, but now the commercial keys are so nearly the proper size thata few minutes’ work with the file is all that is necessary in fitting them. Commercial keys may be obtained in rough or finished sizes, The rough keys are usually from 4 to js in. oversize and are intended tobe finished by hand. These come in handy for making up special keys or fitting one where the keyway has been worn or cut larger than stand- ard. Finished keys require little fitting if the keyway has been care- fully cut. When fitting a key a lubricant should be used. A telltale is als necessary to aid in indicating exact ly where the key is bearing in its seat. ‘To serve this double purpose, white lead mixed with machine of lard oil is excellent. The mixtur should be about the consistency thick cream. (Continued on page 1%) MAY time-saving shop ideas are contained in the continu ation of the Better Shop Methods Department, on pages 119 to 128.

a

Page 71

POPULAR SCIENCE MONTHLY . | “an L. y ir le ll Any man that’s ever worked with a Starrett Combin- ation Square can’t see how it’s possible for anybody else to try to get along without one. _ And they are—those No. 94’s—just about the most useful tool in the chest. They replace seven separate tools—square, miter, height, depth and marking gages, rule, level and plumb—and they’ll do the work of each just a hair better than the original tool would do it. If you haven’t a Starrett Combination Square in your chest now, your nearest good hardware dealer has one that he’ll part with—for a consideration. And it’s worth it. It’s also worth while writing us ¢ Starrett | for a free copy of Catalog No. 23 “W.” ; No. 94 Combination THE L. S. STARRETT CO. World’s Gr Toolmak ) Square IS) Pm te te peg wet Unexcelled - Steel Tapes — Standard for Accuracy 5 : ATHOL, MASS. 276 Use Starrett Tools IS) This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 72

74 Pexto Samson Ratchet Bit Brace OR the mechanic and for general home use, the Pex- to Samson Ratchet Bit Brace, illustrated above, will give a lifetime of dependable service and stand up under the severest ‘“‘roughing.” Its ball- bearing chuck gives the Pexto Brace a grip that never lets go. It will hold round, square or taper-shank drills. The Samson is the kind for you—it’s a boon to the ‘home mechanic.” PEXTO TOOLS are carried by prac- tically all progressive dealers ‘Write for Booklet The Peck, Stow & Wilcox Co. Southington, Conn., U.S. A. Worth While TOOLS POPULAR SCIENCE MONTHLY When there are children in the family, a popular Christmas stable centerpiece is one representing Santa Claus and his reindeers How to Decorate for Christmas Brilliant Window Effects—Lighting the Lawn— Doorways and Stairs—A Table Centerpiece By Cuarves M. MILLER HRISTMAS decorations of the & most original, appropriate and interesting kind are not those bought ready-made in the rush and hurry of last-minute shopping, but those pre- pared in the- home with the merry co- operation of every member of the family. All sorts of ideas can be worked out, as simple or elaborate as you please. In no case is it likely that every one of the suggestions to follow will be carried out in the same home the same year. An effort should be made, however, to de- velop the decorations a bit more than has been customary in previous years. The home decoration may be sub- divided as follows: lawn, porch, windows, Christmas tree, lighting fixtures, arches and doorways, open stairway, and, last but not least, the dining table. Fig. & Decorating the porch light, a lawn lantern, and various methods of ornamenting windows Starting with the newer feature of Yuletime recognition, let the lawn be illuminated at night during Christmas week. If an evergreen tree is growing there, an electric cord can be run from the nearest socket and two or _ three strings of lights hung on the boughs. A breaker or flasher inserted in each of the strings adds to the effect, especially if the strings cross and recross. On other trees hang red lanterns. These may be lighted by electricity or with candles. Homemade lanterns are more appropriate than Oriental. The use of cartons for lanterns simplifies the prob- lem. They should not be large, not over 8 in. to a side. Cut opening designs in the sides of the boxes and paste red paper over the entire outside of the lantern. Crépe paper is best, as the color is stronger and yet softer in effect, but it should not be stretched. Another idea is a box lantern (Fig. 3) attached to a stake driven into the ground, if it isn’t frozen too hard. A light frame- work with a wooden top and bottom is satisfactory. HE porch decorations may include some of the lawn features, but fes- tooned streamers are, perhaps, more fit- ting. An overhead porch light may be inclosed in such a way that all but the downward rays are cut off. Below this housing drop a great many loops of nar- row, bright colored strips of paper and |. some silver and gilt strips as well to give an effect similar to that in either Fig. 1 or Fig. 2. Gloss coated, colored papers such as are used for boxes are good for this, but narrow strips of crépe paper are more transparent. Thrilling effects in color are possible if there is snow on the ground. Three or more colored spotlights may be impro- vised and thrown so as to mingle the different colors on the white surface. Window decorations may have many motifs. The sil- (Continued on page 76) — tS] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Dece

Page 73

POPULAR SCIENCE MONTHLY NEW AUTOMATIC SEMAPHORE NEW LIONE No. 80 & 080 Ta. . HH it SWITCH TOWER is i No. 437 ELECTRICALLY LIGHTED j PULLMAN CARS gore TELEGRAPH POST No. 60 AUTOMATIC TRAIN CONTROL No. 78 & 078 | Nici Patented z MATI coMorive (Electrically Controlled Gates No. = Cao No. 4 oe: Motor, Reversible) ety s if by Magic! —you can run your “Lionel Standard” Train from track to track with the new Train at various speeds, stop it and re- Lionel Electric Switches by manipulating verse it by manipulating a small lever another smalllever placedatany distance placed at any distance from the track. from the track... Lionel trainsand equip- As if by magic—your Lionel Auto- ment have been “Standard of the World” matic Train Control will start and re- since 1900. And now, after years of ex- verse your Lionel Train without being periment, Lionel engineers have ac- touched by hand, and as if by magic— complished the greatest achievement in you can switch your “Lionel Standard” the history of model railroading by creating a The New Lionel 100% isang ree ote ff Electrically Controlled Railroad many styles in the exten- pa sive Lionel Line. for “Lionel Standard” track. every piece beautiful in design, perfect Lionel makes the most complete and in construction, and fully guaranteed. perfect line of model Passenger and They contain hundreds of improvements Freight trains in the world,—both elec- and refinements not found in other lines. trically-controlled and hand-controlled Yet Lionel Trains are the lowest in price for “Lionel Standard” track; and hand- consistent with supreme quality. You controlled for “O-Gauge” Track. Lionel can buy a Lionel ‘‘O-Gauge”’ Train Trains are real in everything except size; for as low as $5.75! See the wonderful Lionel demonstrations at the leading Depart- ment, Toy, Hardware, Sporting Goods and Electrical stores. Send for the NEW LIONEL Model Railroading Book—It’s FREE! This fascinating 48-page book illustrates in actual colors hundreds of Lionel Model Trains, Automatic Railroad Equipment and “Multivolt”” Transformers. Send for it today! Write to Dept. 26 THE LIONEL CORPORATION 15-17-19 East 26th St., New York City AUTOMATIC 4 SIGNAL No. 69 Lionel Coal Car No. 216 Equipped with automatic couplers and hand brakes. Has “Hopper” bottom op- erated by wheel on side of car. Just one of the com- plete line of Lionel freight cars, of all types and sizes. NEW LIONEL pl i CONT =e Lionel Oil Car No. 215 Another striking number in the new series of Lionel Freight Cars. A real oil car in miniature. mS LIONEL STANDARD OBSERVATION CAP $s wing Dome Light aed Rear Fod Laniems “STANDARD OF THE WORLD SINCE 1900” MODEL RAILROAD ACCESSORIES “MULTIVOLT” TRANSFORMERS | © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDAKDS. See Page 6.

Page 74

76 ATKINS “Silver Steel” to Cut Metal «Announcing a wonderful new ATKINS “Silver Steel’’ Hack Saw Blade for hand use. Tests show it will cut six times as long or as much metal and twice as fast as any hack saw blade you ever used. ATKINS “Silver Steel”’ - Blades for metal cutting are a development you should know about and be using NOW. If your dealer cannot supply them, write us and tell us what metal you are cutting and we will see that you are supplied with these new hack saw blades. E. C. ATKINS & CO. Established 1857 Leading Manufacturers of Highest Grade Saws for Every Use; Saw Tools, Saw Specialties’ Plastering Trowels, and Machine Knives. INDIANAPOLIS, U.S. A. ATKINS sue SAWS POPULAR SCIENCE MONTHLY houettes suggested for lanterns may be developed on a much larger scale. Some windows require only a plain holly wreath with a bell inside. A window or two may have an open curtain effect made with ribbons of crépe paper and bells, as in Fig. 4. In Fig. 5 the curves of the paper rope are held in place either with wire or basketry reed. Stars, large and small, may be used effectively on a window, as in Figs. 6 and 9.. The rays are formed with tinsel cord. A common kitchen cleanser that "1 NEWEL |’ post STRIP A, FOR CONNECTION ? OF TWO SIDES OF SLEIGH FIG. \3 Arch, window, door and stair decorations, a simple tree stand, anda miniature sleigh leaves a white deposit on glass can be used for cloud effects. A window may be covered with green Christmas wrapping paper, in which stars have been cut out, and pieces of colored gelatin, such as may be obtained at mo- tion picture supply stores, fastened to the back of the stars with rings of paper. For a design such as Fig. 8, start at one corner sticking on strips of paper about ¥% in. wide; use mainly red strips with a few green, or vice versa. Some fine tinsel distributed rather carelessly over the strips will add life to the design. There are endless possibilities in such an ar- rangement of paper. A spider web may be made with narrow strips. Arches and doors call for festoon de- How to Decorate for Christmas (Continued from page 74) signs. In swinging long festoons, it is best to have one end of each curve higher than the other, as in Fig. 11. In other words the curve should not be too regular, as in Fig. 7, except across small openings, A simple treatment for a plain doorway is shown in Fig. 10. The 3 in. wide red hangings at each side have cross bands of green; the top is green with a red stripe. HE best place for the Christmas tree usually is in a corner of the room, All sorts of bases can be made. Perhaps the simplest is that shown in Fig, 19, The decoration of the Christmas tree has been developed to such a fine art these days that no directions need be given here. As the tree appears to best advantage when lighted, the practice in some homes is to leave the shades drawn on Christmas morning and use artificial lighting during the distribution of the gifts. The effect i3 enhanced if the ordinary lamps in the I'ghting fixture are replaced with globes that have been dyed red and green. An open stairway offers a splendid opportunity for decoration. A_ large candle may be mounted on the newel post, as in Fig. 13. This is a cardboard roll covered with bright red paper. Some real paraffin at the top and a large wick give a realistic appearance. It is still better to use an electric candle-flame bulb. For Christmas dinner the white table- cloth may be decorated with a red crépe paper band about 2 in. wide applied about 3 in. up from the lower edge of the drape. Four similar bands are run across the top of the table about 1 ft. from the edges and parallel to them. An alternative method is to use a 12 in. wide strip of red across the center of the table and a similar strip lengthwise. A green rectangle of crépe paper makes a good foundation for the centerpiece. On this use cotton for snow, with a generous sprinkling of artificial snow. When there are children, a reindeer and Santa Claus centerpiece, as shown at the top of page 74, is especially appropriate. Six small composition reindeers, about 3 in. high, are placed in pairs, with ample room between the pairs. If a cardboard sleigh cannot be found, one can be made of red paper, as suggested in Fig. 14. COMPREHENSIVE article’ on how to set up a Christmas tree, keep it fresh and make the decorations was published in the December, 1925, issue of POPULAR SCIENCE MONTHLY; another article in the same issue told how to prepare a Yuletime decoration for over the mantelshelf. A method of concealing the base of a Christmas tree with a glittering snow mountain was the subject of a long article in De- cember, 1924. Either one of these issues may be obtained, so long as the supply lasts, by sending 25 cents to the Circu- lation Department of POPULAR SCIENCE MONTHLY, 250 Fourth Ave., New York. 1S] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. aN NTO | [rice home a radio 1 What rec ing stati judging the Day- favor of years of | to develo to this 1 believe y operatior Directory its tone ever expr [ M'f'rs with | Your | coupo Card v literat Day-F Name—

Page 75

pecember, 1926 _and at WCAE, the Great Pitts- burgh Broadcasting Station of Kaufmann & Baer Co.— NTO the waiting microphone pours the [roc of the artist—but it reaches your home in its full beauty only if you own atadio receiver capable of reproducing it. What receiver shall it be? Great broadcast- ing stations, themselves listening to and judging their programs for tone quality, use the Day-Fan. We are perhaps prejudiced in favor of the receiver which thirty-seven years of electrical experience has enabled us to develop, so we simply call your attention to this unbiased and expert approval. We believe you will find Day-Fan’s single dial operation unusually simple; its Air Telephone Directory of all stations a great convenience; its tone quality beyond anything you have ever expected of radio. DAY-FAN ELECTRIC CO., DAYTON, OHIO M’f'rs of Radio, Receivers, Fans, and Motors with the Precision of 37 Years’ Experience Your name and address on the coupon line below or a post- card will bring you descriptive literature and address of nearest Day-Fan dealer. No, not al! the noise in your radio is caused by static. Most of it is local, caused by your own small household appliance motors through the house wires. These noises go direct to your set, spoil your entertainment, and get blamed as"* static.’ | Do Away With Local Interference Address. POPULAR SCIENCE MONTHLY 77 they use a Day-Fan Radio Receiver in their Listening Room to judge their Programs— *Among the great Broadcasting Stations who authorize us to say that they use Day-Fan Re- ceivers in their listening rooms to test tone quality and clearness of reception are— WMCA, New York (Hotel McAlpin); WEBJ, New York (Third Avenue Railway System); WQJ, Chicago (Calumet Baking Powder Co. & Rainbo Gardens); WLIB, Chicago (Liberty Magazine); WNAC, Boston (The Shepard Stores); WTAM, Cleveland (Willard Storage Battery Co.); WCAE, Pittsburgh (Kaufmann & Baer Co.); WCCO, Minneapolis and St. Paul (Gold Medal Radio Station, Washburn-Crosby Co.); KFNF, Shenandoah, Ia. (Henry Field Seed Co.); WOWO, Ft. Wayne, Ind. (Main Auto Supply Co.); WOAW, Omaha, Neb. (Woodmen of the World Life Insurance Ass’n); WAAW, Omaha, Neb. (Omaha Grain Exchange); WEAN, Providence (The Shepard Co.); WCAL, Northfield, Minn. (St. Olaf College); KWSC, Pullman, Wash. (State Col- lege of Washington);WCBD, Zion, Ill. (Zion Broadcaste ing Station). Day-Fan Radio Receivers, as used in the broadcasting sta- tions and in thousands of Am- crican homes, are five, six, and seven-tube; priced from $89.00 to $250.00; table and console models; bringing in stations at their newspaper numbers on the single dial control. ©1926 D-F E. Co. Quietus, which has nothing to do with the set itself, is a Day-Fan ac- cessory which stops these noises before they reach your set. Improve the clarity of your reception—write us for information on Quie- tus. Model 6001, illustrated, is for general purposes—oil-burner pump, electric refrigerator, etc. Price $10.00. We also have Model 6003 for home lighting plants. Price $8.00. Day-Fan Electric Co., Dayton, Ohio. Dept. P. S.3. You may send me information regarding Day-Fan Radio aad address of nearest dealer, © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. State

Page 76

POPULAR SCIENCE MONTHLY December, 19% Plain nT Drill ’ Lele Hang SMLDID Ratchet Right-Hand : A finger touch on Ratchet Double Ratchet Gears ML’ Locked The in “VY ANKEE’’ Ratchet is a Short Cut to Results ITH “ Yankee” Ratchet Breast Drill No. 1555 set on DOUBLE Ratchet, any slight movement of the crank, either back or forth, lets you drill continuously. Think what this means when you have space for just a half turn—or only an inch. Nothing need be removed. No lost motion. No lost time. The four other ratchet adjustments shown above, and two speeds, make this “‘ Yankee” Drill the handiest and fastest ever designed. You can change speeds instantly without removing drill from work. Just shift lever at base of hub. Ratchet Breast Drill No. 1555 (Illustrated), 3-jaw; No. 555, 2-jaw. Hold % in. Drills. Ratchet Hand Drill No. 1545, 3-jaw; No. 545, 2-jaw. Hold 3% in. For smaller drilling Ratchet Hand Drill No. adjustments. Write for Free ‘“Yankee’’ Tool Book “‘Yankee’’ Christmas Suggestions No. 1530 Ratchet Hand Drill No. 30-A. Spiral Ratchet Screw Drivers No. 41 Automatic Push Drill No. 1555 Ratchet Breast Drill No. 90 and 95 Plain Screw-drivers No. 1992 Vise with Swivel Base No. 2100 Ratchet Bit Brace No. ro and 15 Ratchet Screw-drivers Dealers everywhere sell “YANKEE” Tools. *“*Yankee’’ on the tool you buy, means the ut- most in quality, efficiency and durability. Nortu Bros. Mre. Co., Philadelphia, U.S. A. "YANKEE" TOOLS Make BetlOv Mechanica Ratchet Shifter gives any one of five ad- justments. jobs use “Yankee” 1530, with five ratchet 1 (At left) Square up and face-mark the wood; set rabbet plane for depth; then rab- bet can be cut 2 (At right) Cut one end of each piece at a 45- deg. angle in miter box; measure each piece in the rabbet; miter the other ends Place an identifi- cation mark on the joints that are to go together and clamp each joint in the vise between two ‘ pieces of soft wood, after which cut the slots with a rip saw 6 When glue is dry, it is time to trim “feathers” with chisel and plane aaa » Misore Frame a FEATHER JOINTS By Emanvuet E. Ericson, Noted Manual Training Authority 3 (Above) Gage for slip-feather slot by run- ning gage against the under _ side, Mark each end of each piece, placing gage line in the ‘middle of the edge feathers of ve- neer or thin wood and insert one in each joint, after gluing both joint and feather. Test frame with square and set aside to dry © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 77

fo get more power put an RCA power Radio- tron UX-120, UX-171 or UX-210 in the last audio stage of your set. Ac@) get more distance fon @ Storage battery set} ~~put the new special detector Radiotron UX-200-A in the detector socket. ¢ ° * RCA is not only making Ra- diotrons steadily better——but is further improving recep- tion with these new special Radiotrons. Keep your set up +o date. POPULAR SCIENCE MONTHLY many times better than in~ 1921. ITH four times less drain on your “A” batteries than the storage battery tube of five years ago, the filament of a Radiotron UX-201-A throws across to the plate five times as many electrons ——a steady stream of tiny electrical charges that carry the song and speech. This is a big increase in efficiency! And the Radiotron UX-201-A does not burn out— unless you apply a huge, excessive voltage. It does not die gradually, but keeps its eficiency almost to the very end of its life. These are buta few of the advances in vacuum tube making that have come from the laboratories of RCA and its associates—General Electric and Westinghouse. Un- ceasing research brings continual improvementin RCA Radiotrons, making possible ever better re- ception-——at lowered cost. RADIO CORPORATION OF AMERICA New York Chicago San Francisco RCA~Radiotron MADE BY THE MAKERS OF THE RADIOLA . IS] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. 3 See page 6.

Page 78

80 POPULAR SCIENCE MONTHLY

be Putting Over Open D > FEROB>

How to Obtain a Professional Finish, Smooth and Brilliant—Materials and Colors to Use By Berton E..iot st RR ORR Bi A EAC ws eee

a \ ipa Aero B Amplipower makes possible on your radio the exact reproduction of every note of every instrument. Deep reso- nant bass notes that are the heart of real music are brought to life with all their rich- ness of tone. When the bass viol booms out its low D the Amplipower will push it through your loud speaker with the deep, resonant clarity of the instrument itself. The Amplipower will make the tone of your radio as much better as the tone of the new talking machine is better than the old, if your set and loud speaker are of the better kind. The Amplipower supplies all of the “B” current for the set, as well as the A,B and C voltages for the built-in high voltage power tube that makes possible greatly in- creased volume with absolute fidelity of

tonal reproduction—both instrumental and vocal. Can be attached to any set in a few minutes,inthesame manner as“B” batteries. c Price $65.00 without tubes. i If your dealer hasn’t the Amplipower or Aero B power unit, write us. Aero B is also built as a ““B’’ power unit without the high voltage power tube —price $50.00 complete.

THE GLENN L. MARTIN COMPANY Radio Division ° Cleveland, Ohio

| to a hospital.

" HERE’S nothing like doing your Christmas shopping early,” laughed Mrs. Andrews, pointing to one of the packages she was carrying. It had been broken open a bit as she entered the crowded bus and something red and shiny was visible through the torn paper. “I’ve got one of the cleverest mechanical toys you ever saw,” she confided. “I bought it at one of the little shops along the avenue. You know, we hadn’t expected to buy any toys this year. John’s been making ’em. Ever since he began read- ing PopuLAR SCIENCE Monruty he’s been making all manner of things, and they most all turn out well.

“Yes,” she continued, = with a flintlike surface hardly stopping for a < ETT, | which will not be softened breath, “we've got it 4 AHA NA up and come off when all figured out. The GY moistened. It cannot toys our kiddies got last year we're going to paint up and give They will be just the same as new to the little boys and girls who haven’t played with them before, and our kiddies will have some wonderful new / playthings to take the place of those they have outgrown or become tired of. “Tm going to paint the ones we give the hospital, but John says the ones he has been mak- ing are his babies, and he wants to do every stroke on them, from first to last. “But do you know,’—lowering her voice—“we’re a little bit afraid of the painting part. It seems simple enough, but I’ve seen some homemade toys that looked crude and amateurish, due more to the poor painting than to anything else. And Cousin Frieda said it was a slow job—hard to keep the kiddies from discovering the toys while they were set- ting around until dry.” “Well, Mrs. Andrews,” I responded, “you and John drop over this evening, and I'll give you some pointers. There really isn’t very much to it, but like everything else you want to do it right.” Later on, just as we were finishing the evening paver, the Andrews came over. “Now, about painting toys,” I began, after we had exchanged a few remarks about other things of casual interest. “There are several different kinds of painting materials you can use. The one that has been most generally used is auto enamel. It has a rich luster, comes in

1 a = P| ' | RS VM bE: Bright red and yellow, in either enamel or lacquer, are the favorite colors for Christmas playthings the brilliant colors that are popular’ toys, and can be obtained in small eg It is also a little more tough and dura than the usual decorative enamels, g will stand better the extremely hard w children give toys. 3 “Then there are the new brush lacquers. As a matter of fact, they ay better adapted for finishing toys than any) other material. They dry in a few utes, so you can get the job done and the toys wrapped up and put away before the kiddies have a chance to come across them. There’s another thing: kiddies always try to put everything in their re mouths and lacquer dries

even by scratched off easily by sharp little teeth. And_ besides, it is perhaps the most durable type of fin- ish. You know the sprayed lacquer fin- ish on automobiles can hardly be scratched with a nail. Brushing lacquer will probably be the best material for you to use—and the most fun.” I pointed out that in the past, before the advent of brushing lacquers, a finishing material sometimes used to speed up the work was white shellac colored with dry colors. This mix- ture dries in an hour or so. The pow- dered colors are obtainable cheaply at almost -any paint store, and many who have had good results with this mixture hesitate to try anything else. “T guess we'll use lacquer,” commented Mr. Andrews, and Mrs. Andrews nodded assent, “The colors,” I continued, “probably have more to do with the homemade look of some toys than anything else. Toys that you buy in the stores are usually finished in bright red or bright yellow. Children are attracted by these brilliant, warm colors, and toy manufacturers have found that where other colors are used their product does not sell. -Therefore, when home toy makers use other colors, the toys don’t look natural, and conse- quently seem crude and awkward. An- other important thing is the proper bal- ance of color. One color must predomi- nate and the trim color must be put on inabout the right (Continued on page 104) J ks

rIS} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 79

RRR ec Rh ete Atty St “tt wy POPULAR SCIENCE MONTHLY Ori king beauty, as well as mic- rometer accura- cy, distinguishes the receiver equipped with MARCO controls. Responsive — to your lightest touch IO MARCO controls fit all condensers. Scales read 0 to 100, or 100 to 0, as preferred. 2 aan dials seem clumsier than e ver. .still more inadequate to meet modern conditions .after one experi- ence with the new MAR-CO control. Nothing approaches its swift, searching response except the celebrated MAR-CO vernier dial itself, 500,000 of which have replaced old type dials. But the new con- trol develops the “friction-drive” principle to the utmost, banishing any suggestion of “backlash” or play And when you switch on the light, a soft radiance illuminates, the moving numerals, adding swifter readability to the scale... and fascinating beauty to the panel. The template supplied reduces panel mounting to a simple 1o-minutes’ diver- sion, whether you are building a new set, or remodelling an old one. The special Mazda lamp runs on your regular “A” battery or on a separate “C” battery. Send for Booklet. Martin Copeland Company, Providence, R. I. MARCO illuminated Controls, $3.50 each MARCO 4 in. vernier dials (fit any set) nickel plated, $2.50 Gold plated, $2.75 New MAR-CO rheostat dial . . . 75¢ IS) MAR-CO J/uminaied Controls © This seal on a radio, tool or oi] burner advertisement signifies the approval of the INSTITUTE OF STANDARDS, See page 6.

Page 80

82 Skilled Labor is dependent on Good Tools AND THEY RELY ON STAR BLADES The new Star Special Flex- ible Blade, produced after 43 years of intensive re- search and development work, combines unusually flexible qualities with the cutting efficiency that has made these blades famous. Tell us about your cutting problems and we will fur- nish you with sample blades that will meet your require- ments. Clemson Bros., Inc. Middletown, N. Y. © MAKERS SINCE 1883 STAR HAckK SAwWs POPULAR SCIENCE MONTHLY How to Utilize Your Cellar One Man Built a Basement Greenhouse— Other Ways of Using Waste Space— A Symposium by Our Readers HETHER or not you are mak- ing full use of the cellar in your home, you will be interested in reading about some of the profitable and ingenious ways in which readers of Porutar Science Monta y have utilized the basement space that is so often wasted. The suggestions that follow were selected as the most practical from the many sent in by those who read the article “How to Utilize Your €el- lar,” in the. April issue, and “How I Improved My Cellar by Making a Coal Vault,” in the May issue. While only two letters are published in regard to the use of cellar space for a workshop and in connection with gardening, a large number of contri- butions dealt with the subject. By W. E. PYKE, Colorado Agricultural College HERE are hundreds of thousands of plant lovers in this country who can get a tremendous amount of enjoyment by building a set of greenhouse frames just outside one or more of their cellar win- dows. Select, if possible, the side of the house that will receive the most sunlight during the winter months, bearing in mind also the direction from which the cold winter winds generally blow. The ground should drain gently away from the frame on all sides. The front and ends should extend far enough into the ground to keep out winter frost, and the earth should be drawn up around the front and ends as a further insulation. The top of the frame should be built rigidly and arranged so that it can be tightly closed in incle- ment weather and at night. If glass is used it should be inserted as in a green- house or skylight. The writer prefers to use either glass cloth or a commercial celluloidlike product and has found them more satisfactory. An additional cover must be provided where the weather is as severe as it is in the northern Mountain States. A blanket or comforter made of old woolens or cot- ton bats arranged as loosely as possible and covered with canvas on the upper side should prove satisfactory. If made in sections, the sections should be over- lapped liberally. The heat for the writer’s frame is pro- vided by keeping the basement windows that open into the frame wide open. The plants of the more hardy type may be bedded right in the frame, while those re- quiring special care are started in the A wealth of bloom every month in the year is insured by this cheaply-built greenhouse usual uniform trays, which are brought into the basement through the windows at night and in severe weather. When the plants become large enough for potting, the pots are placed in trays made to fit the frame for convenience in handling, These trays contain a layer of sand to in- sure perfect drainage and to hold the pots more or less firmly embedded. For soil require- ments, one should have a box of good loam, a_ supply of well-rotted sheep manure or leaf mold, | i» and a supply of sand. i Van. Many books can be | obtained dealing with ,.. this subject. Suffice it to say that if the right methods are em- ployed success will be attained, but the writer would not ad- vise anyone who is not a lover of plants to try the experiment. Small vegetables such as radishes and head lettuce can be grown easily. Flower plants suitable for pot culture in the house can be started in the frame and a wealth of bloom can be had in the house every month in the year. Moreover, bulbs for winter bloom can be started in the early spring from seed. The bulb can be brought to maturity in the early summer and given its period of rest during the remainder 0 the summer. The bulb then may be potted up in the fall for winter bloom. In localities where the growing season is short, hybrid roses may be purcha from the greenhouses and gradually ac- climated in the spring so that they wil not lose their leaves when set in the open ground and a much longer period of bloom will be realized the first year. There are many flower plants that may be started in the frame during January and February (Continued on page 11) IS) This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6- me! An er | sen bet Ste spe red anc set Ren bea piec all 1 —

Page 81

POPULAR SCIENCE MONTHLY ERE are a few suggested Ster- ling gifts for making someone merry at Yuletide. And for months thereafter, the own- er of the Sterling device you pre- sented, will realize you helped make better reception his pleasure. Each Sterling Radio Care-Taker or In- spector plays a prominent part in reducing troubles, simplifying service and adding to the convenience of the set owner. Remember, too, that the radio product bearing the Sterling trade-mark is like the piece of silver stamped ‘‘Sterling”—good all the way through. We suggest you see your dealer for . your selection of Sterling radio devices or write immediately for our interest- ing 32-page booklet showing the com- plete line. The Sterling Mfg. Co. Cleveland, Ohio Sterling Tube Reactivator No. 403 Meter a gue Insures lasting high quality per- formance from tubes—large or small. A money saver as well as a promoter of effi- ciency. Price $12.50. Midget Tube Reactivator (without meter). Price $3.75. Sterling “B” Power No. 97, for ‘‘B’? and ‘‘C”’ power, has far more advan- tages than merely an elim- inator of batteries. Delivers up to 180 volts at 50 milli- amperes, is especially de- sirable for No. 171 and 210 power tubes, and has new type improved Raytheon tube. Price R-97 ‘‘B’’ and ““C” Power, $55.00. Price R-99 ‘‘B’’ Power $45.00. Send for our FREE BOOK on care and upkeep of Radio. It will help toward getting better reception. terls Care-Takers | _ Radio Sets and Inspectors of Sterling Home Tube Tester No. 411 Immediately shows whether tube is good, fair or poor. No com- putationsto make. Price $7.50. Sterling Charge Indicator No. 32 The clean, easy exter- nal test for storage *“*A’? batteries—shows when battery needs charging and when it is charged enough. Price, $2.00. © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 82

84 IF YOU CAN USE AN EXTRA #20 °° BILL write for this FREE}, BOOK] OU can save $20.00 in no time by using SMOOTH-ON No. 1 to do your own household repairing—and in addition you will have that proud “ I-did-it- myself” feeling. Here is what one enthusiast did with two 35 cent cans:—A $25 lamp stand loose in base, two big leaks in heating furnace smoke pipe, loose hammer handle, and three loose hooks in tiled bath room wall were all put into good usable condition at an. average cost of 10 cts. for each repair—and $20.00 easily saved over what would have been paid to professional fixers or for new parts. By using Smooth-On to make dozens of the simple repairs necessary in every home, you can save enough to pay your radio upkeep, buy yourself or your wife a camera, a bull pup or some other pleasure giving article that you would otherwise hate to spend the money for. On the Automobile Smooth-On No. 1, being unaffected by water, oil, gasoline or heat, is also excellent for automobile repairs. Try it for stopping radi- ator, tank, pipe line and hose connection leaks from the outside, keeping exhaust line connections tight to prevent the escape of obnoxious burnt gases, repairing cracked water jackets and crank, gear and differential cases, keeping grease cups, lubricator connections, nuts and ‘hub caps from loosening and falling off, tightening loose hinges, robe rails, etc. The FREE Smooth-On Repair Book How to make HomeE.“AUTOMOBILE _—. REPAIRS will show you how an astonishing number of home and automobile repairs are as easy for you to make as for somebody else. Mail the coupon for a free copy and get Smooth-On No. 1 in 7-02. or 5-lb. can from any hardware store—or if you want us to send a sample 7-0z. can, enclose 35 cts. in postage stamps when you return the coupon. SF Smooth-On Mfg.Co. Dept. 58, 574 Communipaw Ave. JERSEY CITY, N. J. Doit with SMOOTH'ON SMOOTH-ON MFG. CO. Devt. 58, 574 Communipaw Ave., Jersey ‘City, NN... Please send the free Smooth-On Repair Book. NSE 8 ee ee Te NPR tes SG ek Ss Return this coupon Sor : a FREE copy of Booklet POPULAR SCIENCE MONTHLY Mr. Thatcher at the lathe in his workshop. He developed tin can toy making as used in reconstruction work for wounded soldiers You Can Make Delightful OYS from Old ‘Tin Cans By Epwarp THATCHER HEN my boy was about two years old, I searched the toy shops for a large tin locomotive such as I remembered having had when I was a little chap. Failing to find one, I thought of certain tin cans I had saved up. There was a long cylindrical biscuit tin, which would do nicely for a boiler; an adhesive tape box would make a funnel or smokestack, while a square olive oil can would serve for a cab, and flanged syrup can lids would make real- istic wheels. Here was an idea! I hurried home from the toy stores and set to work in my small shop. In an hour or two I had the locomotive made, much to the delight of my small boy. It looked the part; moreover, it was strong, and after many a clattering trip over the sidewalks of New York, we still have it. At that time our whole college (Teachers’ College, Columbia University) had been turned over to the War Department for the training of the occupational aides for hospital service in the World War. In common with the other instructors, I was doing my best to think up some- thing worth while for this work. Tin can toys seemed to be it, and they were. After completing the lo- comotive I made a steam roller, using a can for each roller and another one for a boiler, a flat to- bacco can for a tank, a small flanged lid for a seat, a bot- A realistic model of an Army motor truck made almost entirely from old cans tle cap for the steam gage, and so on. I made several other models and ex- hibited them to the authorities in charge of this work. They approved to such an extent that my entire time for more than two years was given over to teaching tin can toy making. One of my pupils. first took this work to France and I have some interesting pictures of tin can toys made within sound of the big guns by the wounded in a base hospital. They not only made toys, but sink linings, drains, lanterns and candlesticks, Christmas tree ornaments, and many other things. This work soon spread to other hospitals both “over there” and here at home, where I am glad to say that it helped many a poor chap back to some interest in life. William Campbell, my able assistant in teaching this work at college, was of great aid. He first saw the possibilities in tin can toy making for public school work. So the work spread to other schools; it was featured in the newspapers, the movies, and last, but not least, came a wonderful letter, from the British Imperial War Mu- seum, thanking me for my tin can toy models which had been sent over at their request with other American wat toys. These toys are still there on exhibition. And it all began in a very small home work- shop. on page 92) (Continued a ad Saal 0 seit IS] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6 A pe ship i ume ¢ heard TO AG Our Ager naling Ml or part tit of Metrod dyne Rad: wholesale

Page 83

A perfect working, single dial control, 7 tub ship it to your home for 30 days? free trial. heard, return it to the factory. We don’t w evo BIG PROFITS = TO AGENTS AND DEALERS Our — and Dealers make big money selling Metrodyne Sets. You can work all or part time. Demonstrate the superiority of Metrodynes right in your home. Metro- dyne Radios have no competition. Lowest wholesale prices. Demonstrating set on 30 days’ free trial. Greatest money-making opportunity. Send coupon below—or a let- ter—for our agent’s proposition. |= 0 We (Mm Metrodyne Super-Six {nother triumph in radio. Here’s the new 1927 model Metro- 6 tube long distance tuned radio frequency receiving set. Ap- woved by leading radio engineers of America. Highest grade low parts, completely assembled in a beautiful walnut cabinet. lay to operate. Dials easily logged. Tune in your favorite station on same dial readings every time. No guessing. 1, of Chicago, said: ‘“While five Chicago broadcasting stations on te air I tuned in seventeen out-of-town stations, including New n Francisco, on my, loud speaker horn, very loud and clear, as i they were all in Chicago.” are one of the pioneers of radio. The success of Metro- Me sets is due to our liberal 30 days’ free trial offer, much gives you the opportunity of trying before buying. ing POPULAR SCIENCE MONTHLY 1Tube Set le Dial Radio ONLY ONE DIAL TO TUNE Wonderful Offer Direct from the Factory ! e receiver. And just to prove our claims, we will > ; Test it under all conditions, Test it for distance, vol- ume and tonal quality — and if you are not convinced that it is the best single dial ant your money unless you are completely satisfied. Metrodyne Super-Seven Radio A single dial control, 7 tube, tuned radio frequency set. Approved by America’s leading radio engineers. Designed and built by radio experts. Only the highest quality low loss parts are used. Magnificent, two-tone walnut cabinet. Artistically gilded genuine Bakelite panel, nickeled piano hinge and cover support. All exposed metal parts are beautifully finished in 24-k gold. or send a postal or letter.Get our proposition before buying a radio. Deal direct with manufacturer — Save Money. 85 Retail Price $ Completely Assembled Big Discounts N to Agents and Dealers 1 set you ever An easy set to operate. Only one small knob tunes in all stations, The dial is electric- ally lighted so that you can log stations in the dark. The volume control regulates the recep- tion from a faint whisper to thunderous velume, 1,000 to 3,000 miles on loud speaker! The Met- rodyne Super-Seven is a beautiful and efficient receiver, and we are so sure that you will be delighted with it, that we make this liberal 30 days’ free trial offer. You to be the judge. Mail COUPON Below! Let us send you proof of Metrodyne quality F. L. Warnock, Greentown, Ind., writes: “‘I received the Met- rodyne in good shape and am more than pleased with it. Got stations 2,000 miles away.”’ C. J. Walker, Mariposa, Calif., writes: ‘“Received my Metro- dyne Single Dial set O. believe that these one-dial sets are going to be excellent sellers. I had no trouble in tunin in stations enough to satisfy anyone, so you will please sen me another set.”’ Roy Bloch, San Francisco, Calif., writes: ‘Very often we travel from New York to the Hawaiian Islands quickly — from station to station——by means of the little tuning-knob which operates the electrically-lighted dial. The Metrodyne Single Dial Set is much easier to operate than any radio set I’ve ever scen.”’ We will send you hundreds of similar letters from own- ers who acclaim the Metrodyne as the greatest radio set in the world. A postal, letter or the coupon brings complete information, testimonials, wholesale prices, and our liberal 30 days’ free trial offer. SEES E MS USER ERSH SSeS HOw METRO ELECTRIC COMPANY 2161-71 N. California Ave., Dept. 159 Chicago, Illinois Gentlemen: Send me full particulars about Metrodyne 6 tube and 7 tube sets and your 30 days’ free trial offer 1 a ea METRO ELECTRIC COMPANY I-71 N. California Ave. « Dept. 159 + Chicago, Illinois rIS} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. If you are interested in AGENT’S prop- osition, place an “X” in the square &>

Page 84

86 THOUSANDS OF RADIO SET OWNERS need these improvements HE U. 8S. Navy, the Signal Corps, and 69 makers of leading standard sets use the variable resistance controls made by Central Radio Laboratories. These improved controls should be used on your set if you want the last word in quality for fine reception. Yet, owing to our huge output the cost is no more than for many in- ferior devices. Modernize Your Old Set with Centgalab Modu’pluG Tone volume is, as you know, the one big im- provement in this year’s best sets. You can enjoy this improvement with your present receiver for only $2.50. Modu-Plug is especially for that pur- pose. It provides - full tone volume control from , a whisper to maximum, simply by adjusting the small knob on the plug. Matches the speaker imped- ance to the set. Attaches instantly without tools. Standard type Modu- Plug replaces present speaker plug. - Cord type fits sets not equipped with

jacks. Either type, at deal- gl mailed di an. e ee 8 ‘ $2. 50 Centralab RadionM With “A” Battery Switch Here is the variable resist- ance guaranteed always smooth, noiseless and perma- nent in adjustment. Tapered to control oscillation and volume, it also has a positive, quick acting “A” battery switch. One knob replaces two. Turn- ing knob to right lights tubes, then in- creases volume. To left decreases volume, then cuts off batteries. Resist- ance is 0 to 500,000 ohms. You cannot pea gary — eet until you tryit. Adapted to all circuits. At dealer’s, or mail direct... $2.30 R&VARS eostat Where your old design rheostat over- loads, heats-up and quickly becomes noisy on new style tubes using increased current, Centralab Ribbon-type Rheo- stats will operate smoothly and perma- nently quiet. Insu- lated metal discs hold rigid a smooth flat resistance sur- face instead of wires, insuring even regula- tion and no de spots. Every set us- ing this rheostat is improved. 2 resistances for 5 to 10 tubes, at dealer’s, or We mail direct.. $Ue2BS DECREE cor) NO MONEY—Ii resistances your dealer isn’t supplied, order direct from us. for both the Send no money. Simply U.S Navy and pay postman on delivery, eps be "eer few cents postage. Signal Corps nstall and test for 10 d f days. Then if you are an or not more than pleased 6 makers and delighted with the of leading wonderful results, return standard sets

the goods to us and your money will be refunded. 10 DAYS’ FREE TRIAL! Central Radio Laboratories 10 Keefe Avenue Milwaukee, Wis. Cc ian Rep.—Irving W. Levine, Montreal ee Re .—United Distributors, Ltd., Sydney Great Britain Rep.—2. A. Rothermel, Ltd., London POPULAR SCIENCE MONTHLY

Lie Tekorne Worneineya. How to Dress Up the Puzzle of Archimedes F YOU have fallen under the fascinat- ing spell of the Stomachion of Archi- medes—the famous puzzle that drove men wild in ancient times, and, after a lapse of two thousand years, has been revived and made the subject of a prize contest announced last month in PopuLar Science MontTuty—you certainly will want to play this curiously intriguing game with something better than a set of cardboard pieces. A really fine set of the triangles with a case to preserve them will not take long to |

WS A — silicates / YW 9 / . 7 "og Battery Cord

shell, can be easily in-

Cord. For maximum range and volume, ask your dealer for a Beldenamel Aerial. Belden Manufacturing Co. 2304A S. Western Ave., Chicago, Ill.

nS} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

IMPR¢ prove of Ev Here, ent | the ‘ them hatte passe is du desig assen built prod: firml struc space the avoir conn

Page 85

POPULAR SCIENCE MONTHLY MICE ig E gp Sui GRearest Eveready’s exclusive Layerbilt construction makes this the most economical Eveready “‘B’’ battery IMPROVEMENT on top of im- provement has been the history of Eveready Radio Batteries. Here, in the radically differ- ent Eveready Layerbilt, is the “B” battery which tops them all. The ability of this battery to give you. unsur- passed service and economy is due to its unique internal design. Instead of the usual assembly of round cells, it is built of flat layers of current- producing materials pressed fitmly together. -This con- struction makes use of the spaces now wasted between the round-type cells and avoids the usual soldered wire connections. Eveready Layer- bilt is every inch a battery. This exclusive Eveready Bat- tery development packs more active chemicals in a given space and enables them to produce more current and give longer life. Tuesday night means Eveready Hour—9 P. M., Eastern Standard Time, through the following stations: WTAM-—Cleveland wws-Detroit WGN—-Chicago woc-—Davenport . Minneapolis weco { o Paul WEAF—New York wJaR-—Providence WEEI—Boston WTaG—Worcester wFI-Phiiadelphia wcR-Buffalo WCAE-—Pittsburgh wsal—Cincinnati Ksp-St. Louis wRc—Washington Radio Batteries ~-they last longer © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. This Heavy-Duty Ever- EADY LAYERBILT BATTERY gives twice the service of the smaller Light-Duty batteries and greatly reduces your “B” battery operating cost. Use Eveready Layerbilts on any set, and get not only this extra service, but also— the maximum of “B” power operating economy—the ut- most in “B” power depend- ability—D. C. (direct cur- rent) in its purest form, so necessary for pure tone qual- ity. There is an Eveready dealer nearby. Manufactured and guaranteed by NATIONAL CARBON CO., Inc. New York Canadian National Carbon Co., Limited Toronto, Ontario San Francisco

Page 86

88 POPULAR SCIENCE MONTHLY December, 19% _ A*BEC Light Socket Power if Hii] \Ze) dys Ned Sea (AA SS {} tha \ _—— \\ Al TRICKLE CHARGER 00 Wi | re HOMCHARGER Your battery troubles are over, at last. Now all radio power is in your light socket. For continuous unfail a or the Silite Trickie Ch Abso Silite Trickle Ch always at top efficiency. *A” current, connect either the Silite Hom- er to your present storage battery. tely noiseless, without bulbs, moving . parts, or adjustments, arger makes a power unit of your battery—keeps it converts light socket current into radio power and stores it in your battery ready for use at any time—you simply forget about battery ae forever. For oe, large sets where a high charging rate is necessary, the Silite omcharger is recommended. Either model may be used while the set is operating. SILITE TRICKLE CHARGER -6 ampere charging rate. Ee tee ee | $ 1 0 ° 00 SILITE HOMCHARGER 214-3 ampere charging rate. ee ee $19 50 Kodel A&B Transifiers Kodel A and B Transifiers actually deliver all A, B, and C current direct from the light socket—smooth, constant, never-failing F ag that a operates your set always at its greatest e and codiemey power unit, Kodel Transifiers con- from superior to Vv ly different sume current only while the set is operating—maintenance cost is a than one-half cent for every hour you use your set. An ers and Kodel Transifiers. MODEL 10 ‘‘A’? TRANSIFIER Supplies 2, 4, or 6-volts ‘‘A’’® current direct from the light socket. For sets using up to 10 $42 50 tubes e can show you Silite Battery tubes sets up to 6 tu ee eee eee eee ee eee ee eee ee eee) MODEL 61 ‘“‘B’? TRANSIFIER 2214 to 90 volts noiseless ‘‘B’’ power for y radio dea MODEL 10 “‘B’? TRANSIFIER 221% to 150 volts “B’’ current; 4 to 10 volts ‘‘C’’ current for any size set. Operates pcwer $42.50 $28.50 eerrr rrr eee eee eee eee ee ee) (Bulbs extra) ‘Behind the Scenes in a Broadcasting Station’’ an interesting 24-page booklet, will be mailed free on request, together with literature de- scribing Silite Chargers and Kodel Transifiers. The Kodel Radio Corporation, soo E. Pear1St., Cincinnati, O. Owners and Operators of Broadcasting Station WKRC Battery Chargers Power Units KODE Radio Receivers Loud Speakers Power SPECIALISTS Since [912 Puzzle of Archimedes (Continued from page 86) of fiber wallboard or of cardboard taken from a heavy shipping carton can be made attractive if well finished. The first thing to do is to lay out the puzzle as accurately as possible. How to do this was explained last month, and the diagram is repeated in Fig. 1. If cardboard or wallboard is used, it ean be cut with a sharp knife; if wood or harder materials are used, the parts will have to be cut with a fine saw; and some allowance, therefore, will be necessary for the width of the saw kerf. ERHAPS the most convenient size to make the puzzle is on the basis of two 3-In. squares, as in Fig. 1, provided the material is not more than 14 in. thick. With 3¢ in. thick material it is better to use 4-in. squares, but such a set is a trifle cumbersome. If plywood or radio panel material is selected, draw a rectangle 3°% by 63¢ in. and lay out the parts within it so as to allow for the saw kerfs and for finishing the edges. A straightedge clamped to the stock, as in Fig. 2, is an aid in sawing accurately to the line. In finishing the edges of the parts with file and sandpaper, do not trust your eye entirely, but draw another diagram on paper within a rectangle 3 by 6 in. and use it to test each piece. A slightly different procedure is nec- essary when ordinary wood is_ being handled. Draw the diagram the finished size on heavy paper, cut out the pieces, and then mark the wood so that the grain of each piece will run as indicated by the arrows in Fig. 1. If made of wood, the game can be fin- ished with one coat of stain, two coats of shellac rubbed with No. 00 sandpaper, and, finally, a coat or two of furniture wax. An alternative method is to color the pieces with two coats of enamel or brushing lacquer. Compositions such as hard rubber will need no finish except on the edges; these can be shellacked, lac- quered, or varnished. The parts then can be numbered, if desired. HE game is not complete, however, without a suitable case. No doubt the Greeks paid much attention to the container becaus: the game was often known as the Loculus of Archimedes, and loculus referred to the case or cell in which the parts were packed. For 4 in. thick pieces based on a 3-in. square, the box should be 31% in. square inside and a trifle deeper than two thick- nesses of the material used. A neat case and one that requires fairly accurate hand work or the use of a fine cutting circular saw is that shown in Fig. 3. Thinner stock than that indicated may be used and the dimensions modified accordingly, but the lighter the box is made, the more skill and delicacy of workmanship are required. Prepare a piece of the selected wood 4% by 1\% by 22 in. long, cutting a groove 4 in. wide by 2% in. (Continued on page 90) © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 87

en de he he an or ill ne or December, 1926 POPULAR SCIENCE MONTHLY Long Life. No Acids or Liquids Better Radio Reception pETecTOR HIGH Ges & Majestic B’Gurrent Supply delivers pure direct current-From your light socket Majestic Standard — B Capacity seven tubes or six plus one power tube. 45 milliampheres at 135 volts. $32.50 West of Rocky Mts., $35.00 Majestic Super—B Capacity 1 to 12 tubes, in- cluding the use of power tubes, 45 mils at 150 volts. $35.00 i602) West of Rocky Mts., $37.50 Majestic Master—B For Radiola 25, 28 and 30 and Super heterodynes. Op- erates all power tubes. Rat- ing 60 mils at 150 volts. $42.50 West of Rocky Mts., $45.00 Durability @ @ @ © No acids or liquids. Uses Raytheon Tube; no fila. ment to burn out. Dependability @ e Maximum and unvarying power always available. Better Reception No hum, A Superior source of power. Economy e @ e e e Low first cost. Cheaper and better form of “B” Power. Costs only a frac- tion of a cent per hour. Flexibility e@ @ @ @ Voltage can be accurately adjusted to meet varying conditions in every city— and on any set. See your dealer today. Insist on a demonstration on your own set immediately {Can be purchased on deferred payments GRIGSBY ~ GRUNOW~HINDS~ CO. 4578 ARMITAGE AVE, CHICAGO-ILL. © This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. ale ir aba Etta A A AAC EI OETA aera

Page 88

POPULAR SCIENCE MONTHLY producers in the world ? We) SSG | = ay 3 ~~ ay oy WoO Gr GSS AMPLION it, ISS SONY ERSGIEE CONE a $30 Amplion reproduces the entire musical scale with absolute fidelity —no matter what set you have, ‘you need an Amplion to bring out its best Lela Amplion Patrician assembles a 48" air- column with the matchless Amplion repro- ducing unit in a richly carved mahogany cabinet, 18"x 12"x9". The Patrician is non- directional and is notable for the pleasant, soft mellowness of its tone. The Amplion Cone is totally different in principle from any cone type of reproducer. Its especial superiority lies in its clear, clean-cut reproduction of speech. The Amplion Dragon is used as a standard of compari- son in radio experimental laboratories all over the world. To any radio enthusiast no gift could be more acceptable than an Amplion. Prices range from $12 to $45. Ask your. dealer for a demonstration or write to us for interesting Amplion Booklet. THE AMPLION CORPORATION OF AMERICA Suite M, 280 Madison Avenue, New York City From 1887......A path of brilliant achievement ......to 1927 : ~,. Oe gx, AMPLION ioe December, 193% Puzzle of Archimedes (Continued from 88) deep, as at A. and a rabbet 34 by % in, as at B. Cut five pieces with mitered ends so as to be 3 in. long on the inside, Cut the groove from one of these to leaye piece C and from another, to leave piece D. Glue piece C and three others together. When the glue has set, make two narrow saw cuts at each corner, as at EK, into which splines may be glued. The splines (F) are thin strips of wood with the grain running lengthwise. Plane the projecting edges of the splines flush when the glue has hardened. Make the top of 3-in. material. Rab- bet the edges to fit the grooves A on all sides and glue one end in the rabbet of piece D. Makethe bottom of 3%-in. stock to fit the rabbet B and fasten with small brads, BOX as well made as this deserves the finest possible finish. One way of ornamenting the cover is to inlay it witha suitable design, such as suggested in Fig. 4, or one of the solutions to the puzzle illustrated last month. Cut this from a piece of veneer or from very thin wood, lay it upon the top and mark around it accurately with a sharp knife. Make the knife marks nearly as deep as the thick- ness of the inlay, and then remove the wood between the lines with a knife, flat gouge or chisel. Have the recess uniform in depth and a trifle shallow rather than too deep. Glue the design in place and when the glue is hard give it a coat of shellac. The next day, sandpaper the design flush with the surface of the top. The box then may be finished with shellac and wax, lacquer, or varnish. A case of much simpler construction is shown in Fig. 5. Cut two ends 34 by 5¢ by 31% in., two sides 3 by 5% by 3% in. and two pieces for the top and bottom 14 by 3% by 3% in. Nail the corners with 1-in. No. 18 brads. Then make two hinge pieces of sheet brass or tin and fasten with small brass nails as shown. HE top of this box can be left plain or decorated with a design like Fig. 4 drawn in black drawing ink after the wood has been given a thin coat of shellac. In that case, spray another coat of very thin shellac on with an artist’s fixative blower, a perfume atomizer, or a small garden spray, so that the design will not be blurred. The box then may be finished with another coat of shellac and two coats of furniture wax. Fig. 6 suggests a method of making a box of fiber wallboard. Cut two ends 1 by 3% in., two sides 1 by 334in., a bottom 444 in. square, and two pieces for the top, one 414 in. square, the other 31% in. square. Glue the sides and ends at the corners and when the glue has set, fasten this rim to the bottom. Also glue the two top pieces together. This top requires no hinges. The wallboard box should be finished with colored enamel or lacquer. It can be ornamented with a design cut from thin colored paper, pasted smoothly upon the top, and given a protective coating of clear varnish or lacquer. ©. This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 89

SO OS a ee ae ee. _ ee ee 6S yo bE A el ee oe ee ee eS So Se — MN 86 wwe Wm UO BG wee OF te ee —eE we mee fF = 8 ee December, 1926 gx 4 = atk 4 /, fs / st Tycos Instruments Help to Maintain the 7yCos - Iycos Office Thermometers An aid in promoting human efficiency. Freos Bath Thermometers To enable you to get the most good from your bath. Taylor Home Set Bake Oven Thermom- eter, Candy Thermom- eter, Sugar Meter. The secret of accurate re- sults in cooking. Tycos Wall Thermometers To help you maintain a temperature in your house conducive to good health. Medical types. = Proféssior, b for the Tplor Quality Compasses To show you the right way inunfamiliar country. Tycoa Fever Thermometers A necessity in every home. Zycos Stormoguide Forecasts the weather twenty-four hours ahead with depend- able accuracy. Tycos Hygrometer To enable you to keep the humidity of the atmosphere in your home correct at all times. Your dealer will show them to you. Ask us, on a postal, for booklets on any of the above \ iy cl if i Zycos Urinalysis Glassware. Yycos Fever Thermometers. Bulletins on request. ea eee — POPULAR SCIENCE MONTHLY 91 uality ‘of Miylers Candies Says Their Manager of Production j HE NAME HUYLER’S has always stood for quality and purity in our chocolates, ice cream and other confections. This is what the public expects from us and it is what the public always gets. To help us maintain the quality and purity of our products we started using Tycos Instruments some four years ago. The materials contained at one time in one of our holding tanks are worth $300 or more. Spoilage was always a possibility before Tycos equipment was used but none has occurred since installing their splendid heat indicating and recording devices. This represents a definite money saving—but what is even more important our stores and customers are never disappointed by delays due to spoilage. Tycos Instruments are important factors in maintaining the high standards for which Huyler’s has been famous for 51 years. TO MANUFACTURERS If your manufacturing processes require the indicating, recording or controlling of Temperature, there is a type and style of instruments in the Tycos Line of 8000 varieties that will help you. Informative literature on any type of instrument will be sent you promptly on request, or our engineer will consult with you on the application of Tycos to your particular manufacturing process. Iaylor Instrument Companies Main Office and Factory ROCHESTER, N. Y. - «5 Das. wig Canadian Plant: Jcoe BUILDING, TORONTO SHORT & MASON, Ltd., Manufacturing Distributors in Great Britain INDICATING + THE SIXTH SENSE OF INDUSTRY COS Temperature Instruments ECORDING + CONTROLLING IS] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. ae aa WEF ae

Page 90

92 POPULAR SCIENCE MONTHLY December, 19% —- ee Lifts * hs] Tons-~ because the smaller parts are accurately made The combined efforts of many small parts, accurately made, result in this derrick’s lifting 75 tons. Although your work may be an every- day job, a repair job at home or work on a hobby, and the parts may not be required to withstand such a strain, they should nevertheless fit with the necessary accuracy. Tools of Brown & Sharpe Quality help you do difficult jobs more easily. FE ang gi og ed pupa pare when buying tools. If your dealer cannot furnish a copy, write us direct. Micrometer Caliper No. 11 is but one of over 2300 different tools in the complete Brown & Sharpe Line. It measures from 0 to 1” by thousandths of an inch and assures accuracy in small parts. ; BROWN & SHARPE TOOLS BROWN & SHARPE MFG. CO. Providence, R.I., U.S. A. [ee Home Works | Tin Can Toy Making (Continued from page 84) Of all the tin can toys, the steam rol: ler is one of the most typical models This was a great favorite with the wounded soldiers. The illustration on page 94 shows how the different cans are combined to make this toy. The boiler is soldered open end down to the crosspiece between two strips like channel-iron. These make the sides of the frame. These strips and the crosspiece are made from flat strips cut from tin taken from cans, flattened out and folded to shape. The front roller is made from a con. densed or evaporated milk can, as these cans are usually emptied by punching two holes in the top. After the can js emptied it should be soaked in hot water and all the water emptied out before soldering up the holes. A hole is punched in the center of the ends of the can and a piece of stiff wire soldered in for an axle. Between each end of the can and the A soldering iron and tin snips are the prin- cipal tools needed for making toys like this frame is a sort of washer made of a nar- row strip of tin rolled around the axle as shown. The rear roller, which is larger in diameter than the front, is made from a tomato can, or rather two tomato cans of the same size. As the tomato can is longer than the condensed milk can, it must be cut down. A line is scribed around it at the proper height and tinner’s snips are used to cut away the extra tin. Hold the open end of the can toward you and cut from right to left. The bottom is next cut from another tomato can of the same size in such a way that about 3¢ in. is left intact above and around the bottom. This may be done with a sharp can opener, cutting |) around the sides of the can, or by cutting spirally down from the top with the snips, again from right to left. The ring of tin left above the bottom 7 of the can is slit to the bottom of the can | with cuts about 14 in. apart. The can, that is to be used as a roller is then placed over a piece of pipe or similar anvil and the cut end enlarged slightly by hammer- ing it so that the bottom of the other can will fit in it after the notched pieces have been hammered in slightly toward the center of the can. When the pieces fit nicely together, they may be soldered in place. Rollers and wheels of many diameters and (Continued on page 94) © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 91

S ol. Is, he WS jar- as n a 3 of is _ it ar’s Lin. you her ave pasmoell December, 1926 Try this MEASURE YOUR KNOWLEDGE with the POPULAR SCIENCE QUESTIONNAIRE aN) 1. Why does radium continue to give out heat for thousands of years? su.....--- 2. Are the stars solid like the earth? 3. How was the earth formed? .......... 4. Why is glass transparent? -.......-.---- 5. How do we know that the earth is slowly shrinking? -......--.---- 6. What is an electric current? .........- 7. How was petroleum formed? .......- 8. Do electrons really move through wire when an electric current is flowing through it?....... 9. What physical changes in your body are produced by fear?..........-. 10. How do muscles exert power?...... 11. What are X-rays? .......-..-.-..-------c--« ” 12. Can weseeatoms witha micro- scope? 13. Why does heat expand things and cold contract them?............-.. is 14. Why does the moon appear to change its shape from time to ST UTTL 1 RS ey ee eee i 15. What is the brain made of?.......... oe 16. Why is it possible that the in- side of the earth is growing hotter instead of colder? -.............. 17. Why is frost more likely on a clear night than on a cloudy one? 18. Does thinking use up the 19. Which travels faster, electri- city or light? 20. What simple test will distin- 21. What makes the noise of thun- der? 22. Why would men ultimately suffocate if all the green plants were killed? 23. Does the boiling of water re- move the impurities in it? -......... cia 24. How do the living cells of the body getthe energy with which CTafhs bop) soar | if 0) | 3 (eee 25. Howis the speed of light mea- sured? TOTAL PERCENTAGE W.0.nc-on--cneee------ Into this one brilliant book of 284 pages has been con- densed the outstanding facts about the world we live in. SEND NO MONEY Send no money, just the cou- pon. If within 10 days after you receive the book and magazine you decide that you are not sat- isfied in every particular, you a may return them, and your en- tire payment will be refunded promptly and without ques- tion. Could any offer be fairer? POPULAR SCIENCE MONTHLY 250 FOURTH AVENUE POPULAR SCIENCE MONTHLY 93 | Syaemensaee is talking about the famous “Popular Science Questionnaire.”’ Doctors, Lawyers, Professors,College Grad- uates and thousands of others have tested themselves with this Questionnaire. In the panel is the list of questions of which the Questionnaire is composed. How many of them can you answer? Like an Old-fashioned Examination May we ask you to make this test carefully, reading the questions slowly and giving thought to each one? When you cannot answerone satisfactorily to yourself, put a zero (0) beside it. . On the other hand, give yourself credit of four (4) for each satisfac- tory answer. Then when you are through, see how near you have come to making a mark of 100. This is like an'old-fashioned exa- mination, but you will find it fas- cinating. The questions all have to do with the wonders of the world we live in. All can be given quick and straight forward answers by any person of education. All of the questions in the fa- mous ‘‘Popular Science Question- naire’ and many hundreds of others, have now been answered, for the first time, in one book— Tue Pockxer GuipE To ScIENCE. All that you probably ever will want to know about science is told in this one 284-page book that will fit in your pocket or gracea library table. Curiosity-satisfying facts about the world we live in aremade instantly available to you in simple question-and-answer form in Tue Pocxer GuIpE To ScIENCE. You are assured of the ac- curacy of the answers in THE Pocket GuIDE To ScIENCE be- cause it has been edited by months’ su postman 9+. magazine @ 10 days an stamp my ™ NEW YORK TEN muec, offer of bscription to 7.95, plus the OPULAR SC 350 Fourth Ave Laccept yout d the first issue re not d you ar 1 ame in gO! ee Dr. E. E. Free, who has remarkable genius for condensing the known facts about scientific questions in- to easily remembered paragraphs, SPECIAL OFFER Tue Pocket GuIbDE To SCIENCE is not for sale. It is offered to you without one penny extra cost with a 14 months’ subscription to Popr- ULAR SCIENCE MONTHLY. Porutar SciENCE MontTuaty “car- ries on” from where THE PockeT Gu1veE To SciENcE leaves off. THE Pocxer GuibE gives you all that the scientists have discovered up to right now— Poprutar SCIENCE Montuty will give you all the im- portant, interesting and new dis- coveries of science for the next 14 months. It takes over 300 articles and pictures every month to tell the readers of PopuLarR SCIENCE Mont: y all that has happened in the scientific, radio, mechanical and automotive fields. Your Name in Gold Tue Pocxet Guipe To Science is bound in beautiful flexible fabrikoid. We will stamp your name in 22-carat gold on the cover of Tue Pocxer Gumwe at no extra cost to you if you use the coupon below immediately. We extend to you the Special Offer of a 14 months’ subscription to Poputar ScrencE MonTuty (regular price by the month would be $3.50) with the Tue Poc- KET GuIDE TO SclENCE—all for $2.95, plus the postage. If you are already a subscri- ber to Porutar SciENcE we will extend your subscription 14 months if you accept this offer. >. S. 12-26 CE MONTHLY ; 14 id a New Yor uipE TO Seren pay the ostage WHE LY. thin Lisa SctENCE bapa return them wit ° - factory to me . ayment- fully satisfactly refund my full pay e to pr © -This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS, See page 6. 6 eT LEAL, AP ES Riot EE EAM

Page 92

POPULAR SCIENCE MONTHLY Rain and Telephone (alls THE annual rain fall in the United States would weigh over three and one-half trillions of tons. This vast weight is drawn up to the clouds by the unseen but effective power of the sun; rep- resenting energy equivalent to three hundred billion horse- power. The annual telephone conver- sations total over twenty-five billion a year. As silently as sunlight, electricity, mastered by ‘the human mind, carries the voices of the nation. There must be the man-power of 300,000 individuals to build, maintain and operate the tele- phone system. There must be the money- power of over seven hundred million dollars a year to pay for operating the plant, in ad- dition to three billion dollars invested in the plant. The rain sustains life; the tele- phone furnishes swift communi- cation for the nation, and they are alike in requiring a vast amount of unseen energy. AMERICAN [TELEPHONE E AND TELEGRAPH CompANyYy AND AssocIATED COMPANIES SYSTEM . IN ITS SEMI-CENTENNIAL YEAR THE BELL SYSTEM LOOKS FOR- WARD TO CONTINUED PROGRESS IN TELEPHONE COMMUNICATION Read interesting article on Page 4, ‘‘How $100 a Month, Invested Properly, Can Make You Independent.”’ It’s Easy to Build Things! u can perform most any woodworking operation on Boice Bench Machines easily, speedily and at low cost. Send 100 now for Boice’s new 64-page booklet containing helpful information and describing Boice-Bench circular saws, band saws, jig saws, jointers, lathes, drills, mortisers and positive money-back guarantee. 14” Band Saw i Table 12” x 14° ock. ad iades 7 8 tie” d ng Swings 8’. centers. W.B. & J.E. BOIC 8” Bench Lathe to Does turning, drilling, Pals Bearings. sawing, sanding, grinding and jig > sawi in wood or soft metals. “Gapeenty 19” between All Boice Machines driven by % to 4% H. P. motor attached to light socket. Dept. P. S. 12-B Toledo; Ohio Junior Saw ripping, mitering,. grooving, sanding, grinding and drilling with ease and accuracy. Table 10° x13". Saws 24%" stock. Dadoes %°x%%”". Makes moulding. Sold with or with- out motor. Does threading, Tin Can Toy Making ; (Continued from page 92) widths may be made from cans in this way. Another method of making rollers and wheels is to use cans which have scldered caps on each end, such as condensed milk cans. These caps may be melted off in an open flame. A slight knock with an edged tool will remove them when the solder is melted. Another can of the same kind is cut down to the proper width and the piece melted off the first can is sol. dered in place. It will be found that the end melted off the first can will have to ADHESIVE TAPE BOX CONDENSED org CAN . — FOLD ON DOTTED LINES rt Ov H WASHERS (ROLLED STRIPS OF TIN) How the steam roller is assembled; details of frame, rollers, and piston mechanism be enlarged slightly on an anvil before it will fit on the end of the second can. The tank to which the seat is mounted is a pocket tobacco can. This is soldered to the two upright pieces, which are, in turn, soldered to the frame. Strips of tin may be folded into angle or channel-like forms in several ways. The simplest is, of course, to use a regular folder such as the tinner uses. The next best is a wooden roofing folder, but this is not found in the usual tink- er’s shop. Two pieces of hard wood about % in. thick, 2 in. wide and 12 in. long may be made into a simple folder. These are placed in the vise, parallel with the jaws. The pieces should be finished off in such a way that the upper and outside edges of them are chamfered off sharply at more than 45 degrees. The strip of tin to be folded is placed (Continued on page 95) © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. sc] Ww th W | ac

Page 93

December, 1926

POPULAR SCIENCE MONTHLY

—_—_, = = Genome Workshop| Tin Can Toy Making (Continued from page 94)

between these wooden jaws, the vise is screwed up firmly, and then a mallet is used to fold over the tin. The cylinder on the side of the steam roller is a tin adhesive tape box, or a piece of tin rolled into cylindrical form with a bottle cap soldered over one end | for a cylinder cover. ‘The connecting rod is a folded strip of tin, one end of which is soldered to a disk of tin, for a piston. This disk fits loosely into the cylinder. The crank for the rear roller is a piece of stiff wire bent to shape. If galvanized wire is used for the front roller axle and the crank axle of the rear roller, you will find pure muriatic acid best for a soldering flux; soldering paste or “killed acid” is the best flux for tin.

HE steam gage may be made from a bottle cap soldered to the top of the boiler; tinned rivets may be soldered to the side of the boiler for trycocks; a small .22 caliber shell for a whistle; a small can lid soldered to a piece of wire makes a steering wheel. When making the tin toys you will find | that an ice pick or marking awl is an ex- | cellent punch for small holes. | Remember to have all metal to be | soldered bright and clean. Your solder- ing copper must be hot enough to melt the solder easily and quickly, but if it is too hot the tinning at the point will be oxidized or burnt away. The copper then will be useless until it has been filed bright and retinned, by heating it, cover- ing it with flux, and rubbing it in melted solder on a well fluxed piece of tin. Remember, too, that the soldering copper must be left in place long enough to heat the joint to be soldered to the melting point of the solder. After the war we determined to pull up stakes and move to the real country, and make toys. So we came to the shop in which I am at present at work. This is located on a hillside, back of the house, on the site of what was once a tremendous stone pile.

Y FATHER and [I built a track over 250 ft. long, using chestnut two- by-fours for the rails. Later on these “rails” served as framing for the shop. A car was made with a set of wheels from the junk yard. When loaded, this ran by gravity down the track, back of the house, around a curve, over a bridge, and so on out to the new stone pile. The wooden rails around the curve were lined | with strap iron. An incline at the end of | the track stopped the car. We loaded and sent down 396 half-ton loads before we could begin to build the new shop. At last all was ready to start building and my boy Mike drove the first spike in the timber sills. Local carpenters finished this frame and put on the roof. Father and I put on the siding, laid the floors, put in the windows, built the stone forge, and at length com- pleted the shop as it is. The main floor is divided into threr parts such as my (Continued on page 96)

NEW POLICY for the BUSINESS MAN Another Forward Step in a Record of Low Cost and Sound Legal Reserve Life Insurance by the Postal Life Insurance Co. Are you facing an unusual exigency in business? Have you a heavy loan at the bank? Have you a mortgage on the factory? Is the success of your enterprise for the next few years dependent on the present man at the helm? If so, your requirements are met by the POSTAL LIFE’S BUSINESS MAN’S POLICY Issued in Units of $5,000 Based on an experience of twenty years, this Com- pany’s economies are now being morestrikingly shown. The conditions in the Company that have contributed to low cost of insurance will continue, and improve. What Sustains and Helps the Company Standard, Old Line, Legal Reserve Insurance, $50,- 000,000 issued. Income from Insurance and Investments, over $2,000,000 Annually. Standard Policy Provisions Approved by New York In- surance Department. Standard Policy Reserves $12,947,781, as per New York State Certificate of Valuation. Record of Payments to Policy Beneficiaries during Twenty Years: Endowments, Death Claims, Maturing Values, Dividends, Policy Loans, $24,267,790. The Life-Prolonging Serv- ice of the Company’s Health Bureau.

Call at the Company’s office, or simply use the Coupon, or write and say, “ Mail me information as to Business Man’s Policy mentioned in Popular Science Monthly of December” and in your letter be sure to give 1. Your full name; 2. Your occupation; 3. Exact date of your birth. Every standard form of Life and Endowment insur- ance is issued by this company and information as to any of them will be gladly furnished. When your inquiry reaches us no agent will be sent to visit you. We desire to co-operate with you directly, and have you think out with us your problems, from docu- mentary matter submitted. Because we employ no agents the resultant commission savings go to you. POSTALLIFE INSURANCE COMPANY Wm. R. Malone, President 511 Fifth Avenue, Corner 43rd Street, New York

Operated Under Strict Requirements of New York State, and Subject to the United States Postal Au- thorities Everywhere. High Medical Standards in the Selection of Risks. Payment of Premiums Monthly, Quarterly,Semi- Annually, or Annually, Optional with the Policy- holder at any time. Dealing directly at head- quarters for one’s insur- ance. Selecting one’s policy vol- untarily from official data. 914% Dividends Guaran- teed in Policy.

4 P. S. M. 11-26. 1 a Postal Life Insurance Co., — Fifth Ave., New York. } Without obligating me send full par- ticulars for my age as to Business 5 Man’s Policy. REDE a «. o wheias Duel dine ceaetacaeee a ee ey : Decwipatiogs..:.\..24. <icnie- cord aiaesiven beanie \ Exact date of birth. ©..=. 2... es

IS] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 94

POPULAR SCIENCE MONTHLY — Cabinet 1214 inches high 4 rth ?’ By J (| Xi) i | cS } si iy bal i Wi N mi ma i iM i in yi AL EE «|! I | \\ | aa a aN be Ainiih me ui s Price $35 : iN _iN Banishes “Listeners’ Fatigue”’ Forever HEN a loud speaker loses certain notes, your imagination supplies the missing frequencies. You work hard at listening. “Listeners’ Fa- tigue™ results. The new Peerless Repro- ducer has banished all this. A new principle gives amazing results with a 6 inch cone in a 12% inch Gothic cabinet. Gets all the tones, clear, and sweet and full. Any Peerless Dealer will give you the Comparative Demonstration that proves there is a difference. Meantime write for informative loud-speaker booklet, “Voices from the Air.” It is free. Write your name and address on the margin of this page and mail. UNITED RADIO CORPORATION, ROCHESTER, N. A pr eetless REPRODUCER Ne : PLUMBING and HEATING BUY AT WHOLESALE SAVE HALF Send coupon for FREE bargain catalog. Explains our new easy method and _ shows everything in highest grade Plumbing Outfits, Heating Plants, Water Supply Sys- tems, Pipe, Fittings, etc. For 50 years we have been saving our customers hundreds of thousands of dollars and now we have made arrangements so that you can BUY ON EASY TERMS. pr eythes { All-Cast Pipeless Furnace Send us a rough sketch of yourrooms and we will figure the wholesale cost of Heating Plant or Plumbing Out- fit designed especially to fit your home. Kinks and Wrinkles and Savings that will surprise you. With our simplified plans and new easy method you can do the in- stalling. We loan tools FREE. Our Bonded Guarantee is backed by Million Dollar Plant and 50 Years in Business. pan-tayen co. (So establis ~4 7 > : 106-16 W. Pershing Rd., Chica WS pt ee Ai THE COUPON OW poseesecssscesce Hardin-Lavin 06-16W. a TTT P.S.122 Gentlemen: Please send me your REE BA GAIN C ts LOG with special wholesale prices. I am interested in: OC Heating Plant O Plumbing Outfit © This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. TEST FREE The New £200,000 York has perfected a new saxophone! For two years famous dance or- y chestras have been quiet- ly testing it. If you like music, learn about this 88 xophone that cost $200,000 before it was considered perfect. See why it is easiest to learn and play. How it makes fingering easy as running the piano scale. And how it plays popular pones in a short time. EAS TERMS. The — costs little more than cheap, inferior in- struments. Other York Instruments on same easy terms. Simply write for free catalog. Mention instrument Wanted. Use coupon below, O HOUSE OF Bi York Band Instrument Co. (0) (8 6062 OY J.W YORE Dept. 926-L Grand Rapids, Mich. York Band Instrument Co. Dept. 926-L, Grand Rapids, ” Michigan. Yes, send me Free Catalog without obligation. someone to put a coin or ring into it. He ‘guided by metal corner plates as shown. This Magic Box Causes Coins to Disappear eee rings or any small articles Jesg than 1% in. thick can be made to disappear and appear again my steriously in the simply constructed box illustrated This box will astonish an audience of young children. The performer places the box on a table, around: which the children. are allowed to stand, and, opening it, asks BOX 3°x5*5° 7 4, SLIDING 3 Ne BOTTOM, Ys Y) (e Xx ~ SLIDING : BOTTOM ThA THIN METAL CORNER Puls The box has two covers and a freely-sliding false bottom for concealing small objects replaces the cover and goes through what seem to be meaningless motions. When the box is replaced on the table, it is found to be empty. That is because it has been turned upside down and a duplicate cover opened. The object is hidden by a thin, sliding false bottom, The object is recovered by reversing the operation. The box can be made of scraps of wood |, and had best be painted gray inside and blue outside—DonaLp W. Cuark. Tin Can Toy Making (Continued from page 95) previous shop experience had taught me would be convenient, particularly during the cold winters. In the main shop are lo- cated the forge, blower and anvil, gasoline engine, engine and speed lathes, circular saws (large and small), bandsaw, grind- stone, post drill, bench drill, grinding and polishing head, and jointer, all power driven. There are several dynamos of different voltages. Back of the forge is another small shop, complete in itself; in this are the lighter tools for bench work, soldering, brazing and so on, anda small speed lathe and a grinding and polishing head. One of the line shafts runs into this shop. The other room on the first floor is also complete in itself as to lighting and heat- ing. In this room are many of my books and considerable radio equipment. Into this last shop I have tried to build everything I have learned about shops. Much of the equipment I make myself as I find I need it. The junk yard is a happy hunting ground—shafting, pul- leys, belting, gears, and many other things I find there, but I never buy junk unless with a definite idea of using it. And so, to conclude, I find that my shop has done practically everything for me, as I trust it will do for years to come. This is the concluding article in Mr. Thatcher’s series on his adventures in toolcraft, which began in the Septem- ber issue. See page 6.

Page 95

~<A oS Hm oe 2 Oo

POPULAR SCIENCE MONTHLY

(Continued from page 68) and that next. This grip enables one to pack up the paper with his hand, which is an ideal pad. By dipping the paper into the soap solution, then into the yumice-whiting mixture, and rubbing it on the lacquer, we were able to cut down _ | the surface faster than we had expected. We were very careful to rub only in straight lines parallel to the floor. As often as the paper became glazed, we discarded it for a fresh piece. FTER Dan had made a good start, I followed him with a hard, ¥% in. thick rubbing felt dipped into the pumice- whiting mixture. I used plenty of soap solution to keep the surface wet. We cut each section completely before starting on the next. As soon as the work had been rubbed clean, I washed it off with water and a sponge, then chamoised it dry so that I could examine the surface for parts not rubbed enough. ture of vinegar, one part; light machine oil, one part; rottenstone, one part; and water, three parts. With an old cotton flannel cloth folded into a square pad, we polished the surfaces to a brilliant gloss. Last of all, we used a commercial polish made especially for lacquer. When we were through the job was like a mirror, for I could see the beads of perspiration on my head just as plain as day. But it was worth it. “AX TOW that I have the hang of it,” Dan commented, “it seems to me that it isn’t a great deal tougher rubbing than on varnish work. Anyhow, it cer- tainly pays to rub out the body like this. I really can’t say that I like the eggshell finish; it looks like a lazy man’s job.” “That’s the way it appeals to me too, Dan. Do you know, now that we have gone this far with the job, I believe I will take the car over to Jones and Haddock and have them do a little striping work.” And so about two o'clock that after- noon we drove over to the auto shop and had the stripes run on the body. Then I let Dan take the wheel. “Just leave me at the laboratory,” I said, “and you can surprise Mother with a ride for the rest of the day.” And Dan drove off up the street as proud as a peacock. This is the second of two articles on refinishing an automobile with brush- ing lacquer. The preparatory steps were described in detail last month. It should be noted that in buying brushing lacquer for use on an auto- mobile, a brand should be obtained that is recommended by the manufac- turer for this work. Not all lacquers, any more than all enamels, are intend- ed for such an exacting service. Further- more, not all old finishes will stand the solvent action of the thinners used in lacquers, so that the car owner must use his own judgment and make a pre- liminary test on some inconspicuous Part of the car, if he thinks it necessary

Qur next process was to make a mix- |"

© This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6,

Mother be surprised!”

TH the Christmas holidays drawing near, what gift is more useful, more appreciated, than a gate leg table made with the help of your youngster — and good tools? To shape the legs and cross pieces —to round off sharp corners and smooth rough surfaces— use a NICHOLSON Cabinet File (made especially for this purpose). There are many NICHOLSON Files to do the many jobs around the house. Let your local hard- ware dealer help you select the right files. S) MOLS, SSe% U.S.A. {TRADE MARK) NICHOLSON FILE CO. Providence, R. 1.,U.S.A. —a File for Every Purpose

Page 96

**The Saw Makers” NEW PLANER SAW Leaves a Surface of Smoothness Hundreds of plants are replacing their novelty saws with the new Simonds Planer Saws because the Planer © Saw leaves a smooth cut at a faster hand feed than is obtainable with novelty saws. The new Planer Saw can be used for soft or hard wood; for ripping, cutting off, or mitering. And it is made with the same precision and tempered steel that have distinguished Simonds cutting edges for nearly a century. Ask your dealer about the new Simonds Planer Saw. Or write direct for literature and full information. SIMONDS SAW AND STEEL COMPANY FITCHBURG, MASS. . Branches and Service Stations in Principal Cities POPULAR SCIENCE MONTHLY Established 1832 OU install power tubes in your set to get purer tones and to eliminate distortion. Concertones have a large enough core and winding to re- ceive the-lowest notes from the tubes and to reproduce them without distortion or “blasting.” Heavily insulated. i in improved Browning-Drake and other well-known circuits. Ask for free blue print bulletin. Jefferson Electric Mfg. Co. small transformer: 509.8. Green St "Chicago, lil. JEFFERSON (oncertone, rs (AL-2 SEALE D)AUDIO FREQUENCY TRANSFORMERS PARKS WOODWORKING MACHINES $290 with Motor You ought to have this handy Parks in your shop. It is a compact, complete machine designed just like a big produc- tion outfit at one-fifth the cost. Includes 8-inch circular rip and cross cut saw with polished cast-steel saw table, 16-inch band saw with tilting table for bevel-sawing, 6-inch jointer, and motor operating from any light socket. Just plug in and go to work! Fits in a corner of your basement. Does any kind of cabinet and joinery work. Add lathe, shaper and other at- tachments any time at small cost. For the man who does “odd jobs” in his off time this Parks is a big money maker. Turn out as much as a four-man shop working by yourself. Write for circular and Parks complete catalog of handy woodworking machinery The Parks Ball Bearing Machine Co. 1547 Knowlton Street Cincinnati, Ohio December, 1% [Sais ome Wor kaa Toy Birds and Animals (Continued from page 67) More toys from Mr. Hughes’ collection, He is a specialist in their construction corresponding proportions. There jg enough variety to keep you busy for weeks. If you have this blueprint, you cap transfer whatever designs you wish on the wood by means of typewriter carbon paper. Another method, which is quicker if you intend to make a quantity of the toys or have the children help with the work, is to paste the various designs on bristol board or tough, thin cardboard and then cut them out so that they can be used as templets to trace around. Attention is called to the character of most of these forms, with their simple lines and large feet. If these forms had not been changed in this way the smaller parts would split when cut from wood. Tails in most cases should be removed entirely when sawing and leather or twine substituted. It will be noticed also that all of the illustrations of birds in Fig. 9 show only one leg; and of the animals, only the BROOMSTICK fp (Gey MITER BOX °& SMALL SPOOL FOR HUBS —— |], WHEEL CUTTER D CRS ISEASYTO. DRAWING WHEELS WITHOUT A COMPASS E AAA AA I TURNED RODS FOR SMALL WHEELS— READY TO BE SAWED OFF Broomsticks and spools as used for wheels; methods of turning wheels; a wheel cutter cow has all four legs. This simplification, if the toys are cut from one piece of wood, makes the work easier and the result more satisfactory from the stand- em et mm... -= aa -@n eee point of durability. You are not limited to these designs. Many pictures of animals may be found in books, magazines and newspapers, and these may be (Continued on page 99) © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. 7

Page 97

On, the id- aa; # | | base. As a general rule, the width of the Toy Birds and Animals (Continued from page 98) table to wooden toys if sim- meee ihe light of the designs shown. If a toy is to be cut from plain boards, the grain of the wood must be considered and made to run in the direction best serving to strengthen the weaker parts. The different drawings in Fig. 9 have ar- rows to indicate the direction in which the +n of the wood should run. If three- ply wood is used, the grain usually can beignored. What thickness of wood to select de- upon the size of the toy, the form of construction, and, to a lesser degree, upon the kind of wood. Three-ply parts can be thinner than those of solid wood. An elephant made the size shown on Blueprint No. 56 should be 34 in. thick if a | LEAD WEIGHT EYES M\ TO BALANCE TOY ¢ XN Yan” : eset HEAVY RUBBER CORD THROUGH CENTER Toys weighted so as always to remain up- right; ‘‘wiggle”’ toys with jointed bodies single piece, and 5¢ or 3¢ in. thick if in three parts. The cow, cat and donkey should be 14 in. thick if single and 5% in. if in three pieces. The birds and fowl may all be 14 in. thick. The duck can be made into an especial- ly attractive toy if cut from %4 in. thick stock with the head separate and loosely doweled in place so that it will turn. The puppy looks best if 34 in. thick. After the toy has been cut to shape and smoothed with a bit of sandpaper, the kind and style of base should be carefully considered, because the base has much to do with the general attractiveness of the finished article. Each individual toy seems to call for a special type of base and the form should be studied with this in mind. Some toys look best on a round base, others need a square base. If wheels are to be used on the base, the size of the wheels should be con- sidered in relation to the width of the base should equal about one half the height of the toy. In Fig. 3 are shown a number of bases. A and B are removable. In the case of smaller animals for a Noah’s Ark POPULAR SCIENCE MONTHLY To bore clean holes. quickly -- easily without splitting or cracking the HIS on it. write us. on (= GOODELLPRATT and other col- = (Continued on page 100) Use Mr. Punch Here are the eight different size drill points included with Mr. Punch Goodell-Pratt Automatic Drill automatic drill makes holes of any diameter from 1/,, to |/., of an inch—and does it quickly—and clean as a whistle. You push—Mr. Punch twists. No skill is needed to do the job right. No cracking, or splitting, or splinter- ing. Hard wood, soft wood, plaster—are all alike to Mr. Punch. A hollow space in the handle is divided into 8 com- partments, each to hold a drill point of the size marked To get the drill you want, just turn the cap so that the top hole is opposite the compartment the desired drill is in. The point is released through the top hole. Mr. Punch is beautifully nickeled and polished. He is 10 inches long and weighs 8 ounces. Good hardware dealers everywhere sell Mr. Punch. : If yours doesn’t, Send for the book of 1500 Tools Catalog No. 16 pictures and describes each of the famous Good Tools made by Goodell-Pratt. This book is interesting and valuable to every- one who works with tools. It’s FREE. Write for a copy now. GOODELL-PRATT COMPANY, © GREENFIELD, MASS., U.S. A. 1500 GOOD TOOLS © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS.. See page 6.

Page 98

100 100% Perfect Blades to the Package WE don’t do things by halves! We're not sat- isfied just to make Gem Double Life Blades double- keen! We make them double-thick to hold their keenness! We double-rein- force them so they’re double-rigid! We. double-seal and double-protect them so they’redouble-perfect when you get them! Begin to enjoy double- pleasure shaves tomorrow. Buy a double supply today. Sold everywhere. P.S.— You'll get double-satis- Sactionwitha GemdeLuxe Razor. It’s the finest razor money can buy. If your old Gem isn’t right up to perfection, our service de- partment will be glad to replace it! Send it to the GEM SAFETY RAZOR CORPORATION Brooklyn, N. Y. Double Life BLADES POPULAR SCIENCE MONTHLY Toy Birds and Animals (Continued from page 99) lective groups, a small cardboard disk glued to the foot is sufficient. Wooden animals may be made up in a single piece (A, Fig. 1), or in three sections nailed together, as at B. For birds and fowls either a base is used or wheels with a counterbalance (Fig. 7). Small wheels may be made from a broomstick or curtain rod as suggested at A and C in Fig. 6. A stop block placed in the miter box helps to keep the thickness uniform. Two styles of small turned wheels are shown at E. In finding the center and drilling the holes in all of the wheels, care must be observed, or they will be one-sided. A jig with a fixed center can be devised to aid in drilling these centers. For drawing the larger wheels use a compass or pair of dividers or the method shown in sketch D, Fig. 6. If a washer cutter, such as used by steam fitters for cutting gaskets, is to be had, a very good set of wheels may be cut out, provided the wood does not exceed 1 in. in thickness. A satisfactory wheel or washer cutter may, indeed, be improvised as shown at F, Fig. 6. The shank is made from an old auger bit. The larger wheels may be varied in appearance by using different hubs with a plain wheel, as shown at B, Fig. 4. Tin roofing washers used for hubs give neat-looking wheels. Again, several holes may be bored as shown at C, Fig. 4. In the same group E is a painted design that looks well on circus wagons, carts, and the like. At D are shown some exam- ples of turned wheels of various designs. Spindles or bearings for the wheels may oe ““Cute”’ may justly be used to describe some of these brilliant and charming little toys be of several different types, as in Fig. 5. Among the newer wooden toys on the market are to be found some very at- tractive little wheel toys that are weighted so they always remain in an upriglit position. Figure 7 (A, B, and C) suggests how several of these little novelties are made. Beads sometimes may be used as spacers instead of tubes as at A. Some of the semi-mechanical animal toys in the toy shops have one end hinged so that the other can be moved up and down by an eccentric in one of the axles. The principle of the eccentric is indicated at G, Fig. 3. The jointed toy made in several sec- tionsand arranged (Continued on page 101) December, 19x, : | The Crown Fuel Saver wilj give more heat, steadier heat, than you ever before suc. ceeded in getting from aq given amount of coal—and will lower your coal bills. CROWN 1 Ff nee SAVER Mix€s D HOT mint | (A9 YGEN F - GASES OVE I fxs T= FURNACE FIRE BED: SAVES 20% of FUEL © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. You can have the cosiest, warmest home this winter by simply attach- ing the Crown Fuel Saver to the feed door of your heating plant. By doing so you will save at least 20% of the coal you usually pay for—get decidedly more heat from the coal you burn—reduce the number of firings—and keep every room livable and comfortable. The Crown pays for itself in comfort alone—in healthful heat that conquers cold and dampness. The Crown pays for itself in actual money. For, we absolutely guarantee the Crown to save at least 20% of the coal you ordinarily use, or we will refund its purchase price without argument. Figure this 20% saving for any period of from a year to ten years on the basis of ° the amount of coal you used last year. Quite a considerable sum isn’t it? A big enough savings to make it worth while for you to investigate the inexpensive Crown Fuel Saver. Works automatically The Crown is easily attached to the feed door of your heating plant (put it on yourself or get some “handy man” to do it)—works automatically— never gets out of order. Proved by 11 years’ use The Crown Fuel Saver has proved its merit as a coal saver and heat producer in thousands of homes, apart- ments and factories. Write today for full description and for special low price of Crown with money-back guarantee. Do it today. You'll be lots more comfort- able this winter with a Crown on your heating plant and you'll make a substantial money-saving. CROWN FUEL SAVER CO. 112 No. 10th St. Richmond, Indiana DISTRIBUTORS WANTED—The Crown Fuel Saver and the Crown Smoke Preventer (for industrial power plants) offer a worthwhile opportunity to ambitious men. These devices cover every need in the home @ industrial heating field. Write for details of our exclue sive territory franchise. ——— son C1 ho Ff = See So = 5S les Se GON a es ees es Ones 0s 3 ee ee) ee a ae ee ee ene ee SU le ee)

Page 99

J towiggle when it is drawn along is always it dious harp with its short and long nt strings, the short and long sides of the C- Ec-centric Cone provide vibrating area | - — i and low notes. Novae pletely eliminating or barre! a tone, Operates equally well with or Saal Horn No. 5 id without power amplifier, Price, —[ater model of the famous POPULAR SCIENCE MONTHLY Toy Birds and Animals (Continued from page 100) ‘ateresting to the children and quite simple | in construction, as shown 1n Fig. 8. | The main points in successful toy mak- | ing are simple lines, solid construction, and clear, bright colors. For most of the smaller toys the gloss paints, carriage or auto enamels and Saal Ec-centric Cone —based on the principle of the melo- $25. Junior model, $15. All prices “Saal Soft Speaker.” Bell of slightly higher west of the Rockies. genuine Bakelite, goose neck of cast alurainum. Nothing to warp crack or deteriorate. No metallic ring. Guaranteed not to blast or st h- 1e at ve ye ce of Of 1g le e ok ivtreTe Feenn B NES MAY BE ENLARGED TO ANY DESIRED SIZE BY LAYING OUT LARGER SQUARES Full size templets of these toys are con- tained in Blueprint No. 56. See page 102 colored lacquers have been found most satisfactory. For simple work the three primary colors, bright red, clear, brilliant blue, and yellow, with the addition of black and white, are all that are needed. | These may be combined to form all the others. The work should be given a priming coat first, and when this is dry, the colors apjlied in the order of the | lightest first. As a rule it is best to let ‘| each color dry before applying the others. Eyes and small lines may be added with the point of a nail or a toothpick, if a small pencil brush is not at hand. For additional suggestions about painting toys, see page 80. chatter. As u: neers in laboratory tests. Price, $22.50. Oy mie eat Saal Pedestal —Can be readily moved to any desired room or posi tion. Tones emerge from both front and back of gold The best set in the world ts winston your ear when you are seated tuning in. Rich only as good as its speaker 8" SAAL: Jot SPEAKERS bring out every note your set receives Are you one of those who blame their radio sets for unsatisfactory performance and give no thought to the speaker ? The chances are your receiver gets all that is on the air, but your speaker reproduces only part. Before condemning your set make sure your speaker is a scien- tific, up-to-date reproducer. Any one of these three Saal Speakers will bring the most out of your set. It is only a question of preference in type. The SAAL Ec-centric Cone is the year’s outstanding develop- ment in the cone field. Its short and long sides are scientifically balanced for sound reproduction. For the first time a cone speaker of only 20 inches diameter repro- ducesthe slightest whispers of the human voice. For those who prefer the type of speaker used byradio engineers in experimental and test work, the SAAL Horn is unsurpassed. Its goose neck of non-vibrant aluminum is based on the scien- tific musical design of the mellow saxophone, A speaker that may be readily moved from one room to another is the SAAL Pedestal. Its long gradually tapering 3-foot wooden tone chamber reproduces all the notes with the same richness and clarity of all SAAL Soft Speakers, All SAAL Speakers have the same standard of complete tonal reproduction, Solidly constructed, the SAAL Speaker you select now will be the last you ever need buy. H.G. SAAL COMPANY, 1800 Montrose Avenue, Chicago, U.S.A. WORLD FAMOUS MAKERS OF HORNS, CONES, PEDESTALS r{S] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See nage 6.

Page 100

102 TRIMO The Pipe Wrench ForAllEmergencies

When it comes to mak- ing! repairs TRIMO Pipe Wrench is unsur- passed in design, effi- ciency, strength and han- diness. Buy several sizes to meet all emergencies. Remember—this is THE Pipe Wrench that has a replaceable INSERT JAW in the handle— that its pressed steel frame WILL NOT BREAK and the NUT GUARDS onthe TRIMO which keep this wrench adjusted in close quarters guarantee quick, continuous work. While the teeth of the TRIMO grip firmly, they will not lock on the pipe, but release readily. Eight steel handle sizes from 6 to 48 ins.; four wood handle sizes, 6, 8, 10 and 14 ins. TRIMO Monkey Wrench The Trimo Monkey Wrench is sim; in construction, has y three main parts, is practically indestructible, and its strength has been proved by actual test. Seven standard sizes, 6 to 21 inches. Fully guaranteed. TRIMONT MFG. CO. ROXBURY, MASS. 313 NS Se A TT

POPULAR SCIENCE MONTHLY

[Mie Tlome Workshop | Blueprints to Aid You in Making Toys OU will agree, no doubt, that toy making is the most fascinating work done in the average home workshop. Three of our blueprints are devoted to toys. Details of an electric train, a kiddie broncho, which is a toy for small children to ride, and a 20 by 36 by 36 in. doll’s house are given in No. 14, listed below. Drawings fora toy tea cart and game table, a toy garage, and a bunny wheelbarrow, are contained in No. 29, and for many fret-sawed toys in No. 56 (see page 67).

Complete List of Blueprints NY ONE of the blueprints listed below can be obtained from Poputar Science Monrtuty for 25 cents. The corresponding back issue of the magazine, in which the project was described in detail, can be had for 25 cents additional so long as copies are available. The Editor will be glad to answer any specific questions rela- tive to tools, material, or equipment.

Popu.ar Science Montuiy 250 Fourth Avenue, New York GENTLEMEN: Send me the blueprint, or blue- prints, I have underlined below, for CN Sree cents: Described in Issueof Price Feb., °22 25c No. Title 1. Sewing Table 2. Smoking Cabinet 3. End Table 5. Kitchen Cabinet 8. Shaving Cabinet 9. Arbor, Gate and Seats 10. Porch Swing 11. Bench and Tilt Table 12. Electric Washer 13. Tea Wagon 14. Christmas Toys 15. Workshop Bench 16. Inlaid Radio Cabinet 17. Cedar Chest 18. Phone Table and Stool 19. Grandfather’s Clock 20. Flat Top Desk 21. Colonial Desk 22. Cabinet and Desk 23. Pergola Garage 24. Gateleg Table 25. Canoe Sailing Outfit 26. Baby’s Crib and Pen Sept., ’23 25c 27. Kitchen-Cabinet Table 28. Pullman Play Table 29. Toy Tea Cart, etc. 30. Tool Cabinet, etc. 31. Sewing Cabinets 32. Chinese Game Table 33. Dining Alcove Apr., °24 25c 34. Garden Trellises 35. Simple Radio Cabinet 36. Rush-Bottom Chair 37. Simplified Bookcase 38. Sheraton Table 39. Salem Chest 40. Desk in Sheraton Style 41. One-Tube Radio Set May, °’25 25c 42. Three-Stage Amplifier June, °25 25c 43. Four-Tube Receiver uly, °’25 25c 44. Pirate Ship Model—Hull Feb., °26 25c 45. Pirate Ship—Details Mar., ’°26 25c 46. Galleon Model—Hull May, °’26 25c 47. Galleon Model—Details June, ’26 25c 48. Sailing Yacht Model July, °’26 25c 49. Broom Cabinet — 5 2 5c 50. Airplane Model (Flying) Sept., °26 25c 51. Clipper Ship Model—Hull On. °26 25c 52. Clipper Model—Details Oct., ’26 25c 53. Clipper Model—Rigging Nov., 7262 2Sc 54. Five-Tube Radio Set Oct., 26 25c 55. Five-Tube Set—Details Oct., °26 25c 56. Bird and Animal Toys Dec., °26 25c > foe © J ) > nd 7) a a. SUT ec Cah bp De 5 Sside kb ee <k QeskSe awe (Please print name and address very clearly) Ee ee ee eer re eT Why the Price of this Colonial Tilt-Top Table is Only $ Sells Everywhere for $25 to $30 Yeap can save at least $15 by getting this beau table from us in plain, close-grained, ahah wood. Decorate it yourself in the smart colore enamels that the latest vogue in home decoration requires, It is easy as A. B.C. No experience needed, Complete Decorating Instructions and Materials Included This handsome tilt-top table is 28 in. high, T across.Center post3% in. diameterat base wohonis smooth-flowing enamels, brushes, color-scheme, ete, free. Ten colors to selectfrom—see coupon. two colors, one for body and one for trim. Tables flat—for convenience. Holes drilled, screwsf = be put together in 5 minutes with only a screw ver, Satisfaction Guaranteed Send no money now— just the coupon. When table arrives pay postman $9.75 plus postage, Money back if dissatisfied. HOMECRAFT STUDIOS, Inc. Dept.1212__ Wisner Bidg., Rochester, N.Y, ad i ee eld —— = OE oe oO oy HomecraFt Stup108, INc., Dept. 1212 Wisner Building, Rochester, N. Y. Send me the Colonial Tilt Top Table, with free ma terials and instructions for decorating. I will give the tman $9.75 plus postage which you will re fund at once if I return the table and materials with- in 5 days. Send me colors of enamel checked.U Black 0) White 0 Chinese Red_( French Grey O Lettuce Green Grass Green O Dark Blue UL Light Blue O Orange OC Ivory. Name eeece SO CSOOSSHOSSOHEOSES SES SEHESSSSOOOOSHOSOEN eeereesscesscescceses eeecececccsecsesese eeeeeer Clty. cccccccccccceccccccccccce oo State. ...cccs ccm

ris] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

FIXED RESISTORS | ARE WARRANTED— Absolutely Noiseless © Permanently Accurate Gist Dependable / Write us! ARTHUR H. LYNCH, Inc. Manufacturers of Radio Devices

Fisk Bidg., Broadway & 57th Street New York, N.Y. SSRI RO SASS SSR SSAA IR SORT BASRA ATR ISIS

Page 101

"REiEE 4%} ge e RE gRage POPULAR SCIENCE MONTHLY S rick TheT a Fuse Chart | By GEORGE A. WILLOUGHBY ‘sor of Electric Work, Arthur Hill Re rradt School Saginaw, Mich. oa were going to show me how remin inded me, as he came ame the ‘veway that separates our houses. Pika: won't take long,” I assured him. “Come in and we'll make one out for my house; then we can do the same over jn your place. You see, there is a great advantage in having a fuse chart, be- cause if a lamp fails to light or any elec- tric device won’t work and the trouble seems to be a blown fuse, it is possible to tell at a glance where to look for the defective fuse. It isn’t necessary to hunt around for it as we did the other day when you had trouble in one of the up- stairs circuits. There are only two fuse blocks in my house, but, nevertheless, the chart is worth making. The chart for your house, which has more circuits, We removed two fuses, one from each block, and screwed a lamp in each vacant receptacle First we made out in duplicate a list of all the lights and convenience outlets in the house—kitchen ceiling light; kitchen convenience outlet; living room center lighting fixture; living room con- There were seventeen. house switch and put a lamp into one fuse receptacle in each fuse block, after removing the fuses from these two re- two fuses. switch. “By watching these lamps,” plained to Rice, “you can tell which set of fuses protects each outlet. You stay right here with one list while I go through the house and turn on and off everything in the same order as the outlets appear on the list, from one to seventeen. When the lamp in the first fuse block lights, put down number one on the list opposite the proper outlet. When the other lamp lights, mark down number two.” This checking process was carried out quickly and the completed chart was hung opposite the fuse box for reference. Then we went over to Jack’s house and used exactly the same method to prepare & chart for his much more extensive Wiring system. to make a fuse chart,” Jack Rice | can be worked out in the same way.” venience outlet; west wall; and so on. | Going to the cellar, we pulled the main | ceptacles. We did not disturb the other | Then we closed the main | I ex- | “EUy are bug ie UNITED STATES ARSENA»”. ty ERlONAL MUSEUM. AND ome SRK ON py AND ARTISANS THRO) (ANOS ORGANS. R.R.G Handiest Tool in Your Work Shop PERHAPS you have never thought of the special advantages of using LePage’s Liquid Glue. It is always ready for immediate use. No weigh- ing, soaking or heating is required. Its quality is always the same. It ‘‘sets’’ slowly enough so that you have plenty of time to place the joints together exactly as they should go. Slow setting also allows LePage’s to penetrate the wood, increasing the strength of the joint. Le- Page’s Liquid Glue is equal in strength to any animal glue. Buy a can for your workshop. It is the easiest, quickest, handiest form of Glue. Insist on LePage’s. Recipe for Making LePage’s Gesso To make one cup of LePage’s Gesso, you need 1 gill can of LEPAGE’S GLUE, 1% cups whiting, 3 teaspoons linseed oil and 3 teaspoons varnish. Place whiting in mixing bowl and pour in slowly in this order. LEPAGE’S GLUE, linseed oil, and varnish: Mix until smooth. All ingredients obtain- able at nearest hardware store. lt PAGES # PRACTICAL if peta a Seed \ ti PuBUSHED BY THE Man oF Pes « uv paces GLUE i AGE’S GLUE ‘Bottles, Tubes,Cans E Try this NEW way to improve your Craftsmanship LePage’s New Books will show you how ITH the coming of thelong winter evenings, the best time of the year is here for the man with the Home Work Shop Hobby. What articles of furniture are you planning to make this winter? Whether it is a radio cabinet, end table, book case, cedar chest, or any other piece of household furniture,: LePage’s New Books can be of prac- tical help to you. ‘‘LePage’s Practical Suggestions for the Home Work Shop,” and, ‘‘LePage’s Gesso-Craft Book,” will help you come closer to equalling the skill of the trained cabinet maker, turning your evenings spent on this hobby to better account. They tell you how to make strong joints with glue, and not only with glue, but with glue in its most con- venient form—LePage’s Liquid Glue. These books also show you how to cover up small defects in your crafts- manship. Now and then a tool will slip and an error is made. Or there are holes to be filled where nails or screws have been countersunk. Or the edges of a joint are not exactly. even. A simple new way to repair these defects is with the use of LePage’s Gesso instead of putty. LePage’s Gesso will stick to any surface—wood, metal, glass, etc. It can be sandpapered, planed and painted or stained just like wood. We give you in the small panel at left a simple formula for making LePage’s Gesso, but of course we tell you more about it in the books them- selves, together with practical informa- tion on decorating your finished articles with Gesso. Send 10 cents for these NEW LePage’s Books THE practical and useful help of these two books is yours for only 10 cents. Just write your name and address on the coupon below,. téar the coupon out and mail it to us today with 10 cents in coin or stamps, and we will at once send you a copy of these two LePage’s Books, post- age paid. Address LePage’s Craft League, Dept. 00-6, Gloucester, Mass. Tear out the coupon now so you will not forget it. | Dept. 00-6, Gloucester, Mass. | Gentlemen: Enclosed you will find 10 cents (coin or stamps) in payment for | ‘‘LePage’s Practical Suggestions for the Home Workshop,” and ‘‘LePage’s Gesso- | Craft Book.” Please send acopy of each to: i . | | LEPAGE’s CRAFT LEAGUE, 7 © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Saleen Cann eet A

Page 102

knows The man who has a hammer in his fist a good part of every work- ing day picks the May- dole. He knows that no other hammer has quite the same quality of ma- terials and care in manu- facture and inspection. The head is press-forged of selected tool steel, each end tem- pered separately. The handle is of clear, second- growth hickory, air-dried for % years. If you consider it good common sense to use only the finest tools, it will pay you to insist on the gen- alas eB iP il uJ uine Maydole. MAYDOLE ° Write us for in- Ball Pein teresting and use- A bile nc ful Pocket Hand- book 23 “‘B’’. Maydole Hammers The David Maydole Hammer Co.Norwich NY p 9 POPULAR SCIENCE MONTHLY ie iaonde Wornsenon| Fun in Painting Toys (Continued from page 80) amount and the right places, or it won't look right. It is a good idea to take a little trip through some toy shop, or the toy department of one of the big stores, and make a mental note of the color combinations.” “That seems logical,’ Mrs. Andrews chirped, as I paused momentarily. “The mechanical part of the work needs to be well done,” I resumed, “but there’s really nothing to it, after the fine interior decorating you folks have been doing lately. In doing the new toys, the first step is to sandpaper the wood. If it is somewhat rough, cut it down to com- parative smoothness with number one half sandpaper. Then smooth it off with number 00 sandpaper. Always sand with the grain of the wood.” HEN I described in detail the process of painting. It is, of course, quite possible to apply the auto enamel or lacquer directly to the bare wood, but a better finish is obtained and time is saved in the end by preparing the surface with a coat of white shellac. This seals the surface and usually saves a coat of the enamel or Jacquer.. The shellac dries in about half an hour, and should then be sandpapered lightly. If there are any cracks or imperfections of the surface, they should be filled at this time with some crack filling prepara- tion. Putty is all right if it is pure linseed oil putty. The trouble is, however, that much putty is made with paraffin oil and this will begin to show through and dis- color the painted finish soon after it has been applied. There are crack filling prep- arations put up especially for use on wood surfaces; they cost a little more but are much better. These will not discolor suc- ceeding paint coats; they dry hard more quickly, and are less liable to shrink and come out. One trouble with either of these materials for this purpose is that they should be allowed to dry until the next day before being painted over. When it is desirable to finish up the work the same day, about the best thing is to mix up some plaster of Paris or whiting with white shellac or lacquer. This will dry so hard within an hour that it can be sandpapered level and smooth. 7. coats of either enamel or lacquer ought to be enough over the shellac, but a third coat sometimes may be neces- sary. If auto enamel is used, allow forty- eight hours for drying, and sandpaper lightly between coats. If lacquer is used, the sandpapering between coats may be dispensed with; in fact, it will be better not to sandpaper if you are going to follow one coat after another within an hour or so. Lacquers, while they are dry to the touch within a few minutes after applica- tion, continue to harden for quite a few hours, and if the lacquer is to be sanded it should be dry clear through. Another thing to remember is that lacquer will not stand so much sandpapering as oil paints and varnishes, and should never be sand- papered dry. (Continued on page 105) Cee WET CELLARS MADE Dy from the Inside AMP musty cellars are unsan. itary, a danger to health and a poor place to store valuable materia] Where water or moisture see = through cracks or porous spots in the floor or walls, you can make and keep your cellar dry and sweet—a fit place to work, free from odor, mold and rust—by filling the cracks and coating the moist surface with Smooth-On No. 7. This is the one practical waterproof- ing that you can ap- ply yourself, easily, from the inside, to wet or dry surface and with every as- surance of thorough watertightness, even in the wettest sea- Write for sons, . FREE BOOK Excellenj also for patching concrete floors, waterproofing garage, stable and washroom floors, brick walls, cisterns, septic tanks, water troughs, fountains, fish ponds,, swimming pools, manure pits, etc. About 25 pounds of e_> Smooth-On No. 7 are pe —— ee] quired for each 100 square feet of surface covered, and 4@ mo experience 1S necessary, ‘4 Complete instructions on the package. Sold in 5-pound cans and 25, 50 and 100-pound kegs. FREE copy of Booklet eB RE SMOOTH-ON MFG. CO., Dept. 58, 574 Communipaw Ave., Jersey City, N.J. Please send the free Smooth-On Repair Book Quote priceon...... Ibs. of Smooth-On No.7: DARING. 6 cedar aes ese ess see 6 oe es ee TEE Return this coupon for Provides complete noiseless filament con- trol for all radio tubes withoutchange of con- nections. Metal parts are nickel plated. One hole mounting. Self contained switch opens battery circuit when 293 Greenfield Avenue Milwaukee, Wis. tS) This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 103

— oD € e Worlkksihiey | Fun in Painting Toys (Continued from page 10.4) The dry paper scars the lacquer film. Get the special type of sandpaper made for use with water and keep it wet. After sandpapering, always be sure to dust off the surfaces. About the only other thing to remember is to watch out for sags or beads forming and running down at the corners and edges, also “oyrtains” on upright surfaces. When seen, these should be “picked up” or “straightened out” with the brush at once, before the material has commenced to set. As toys generally are more or less irreg- ular in design, care is essential so as not to cut through at the edges or corners in sandpapering, and not to miss any places in applying each coat. Look over every part carefully for skipped places. In refinishing old toys, simply wash them, sandpaper lightly and give them a coat of enamel or lacquer. One coat ordinarily is enough for a repaint job, but if not, apply another. “With these pointers we'll surely make a good job of it,” Mr. Andrews asserted when I had finished. “There’s one thing more,” I added. “The finish wants to be flowed on smooth- ly and evenly, without showing brush marks. You'll need good brushes if you want a good job. About a one and a half or a two-inch brush will do nicely for this work. And then you ought to have a smaller brush—about a half inch—for putting on the trim color and other small work.” “Now then, we're all set for playing Santa Claus!” exclaimed Mrs. Andrews. How to Apply Leather Hinges aie hinges, if used on the lids of boxes or chests around the shop and home, should each consist of two pieces. One is fastened to the underside of the lid and passes through a recess in the edge of the box so that it can be attached to the outside of the back. The ad- jacent piece is at- tached to the out- side of the top, passes through the recess, and is fas- tened inside the L back. The lid Can- Each hinge requires not slide forward two leather strips and backward. Either screws or nails long enough to be clinched may be used for attaching leather hinges.—Haroip N. Wuttrmore. An EAsy way to remove lint, waste or other fuzzy matter from a metal strainer or screen is to dip it into gasoline and light it with a match. The charred waste material then can be blown or shaken off If the screen is soldered, the waste must be lit and extinguished repeatedly to avoid any chance of the solder’s melting. POPULAR SCIENCE MONTHLY A Git Pat aP ata M ahaa a Mata aM aa aaa | Bs gee T= annual question is in every- 4 body’s mind. The annual gift list is in everybody’s pocket. Here is just the right present for son or daughter, for best friend, for close business associate—in fact The Remington Portable Type- writer may be selected with the assurance that it is the recognized leader—in sales and popularity. It meets every requirement of per- sonal writing. It is the world’s lightest writing machine with standard keyboard—tips the scales at only 814 pounds net. And it is the most compact of all typewrit- ers—fits in a carrying case only four inches high. It is faster than the speed de- mands of even the most expert user; and its dependability is Rem- ington dependability. From every standpoint it is the gift for everybody. Terms as low as $5 monthly. Sold by Remington branches and dealers every- where. Send for our booklet ** For You— For Everybody.”* Address Dept. 67. REMINGTON T yPEWRITER COMPANY 374 Broadway New York Branches Everywhere § Remington Typewriter Company of Canada, Led. 68 King Street, West, Toronto t for Gverybody emington ypewriters A MACHINE FOR EVERY PURPOSE rer FYPEWAITERS TYPEWRITERS MACHINGS ® This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Remington -made Para- gon Ribbons and Red Seal Carbon Papers always make good impressions

Page 104

Dubilier Ducon Price $1.50 Aerials have gone out of style « @ & In the old days, when radio was new, the “fan” was known by crazy fes- toons of wire that decorated his housetop or yard. These were the old- fashioned aerials, and no one has for- gotten all the grief they caused. Modern radio may use the hidden loop, or the short indoor aerial. But there is a better way. The Dubilier Ducon enables you tc use the com- plete wiring system of your house without risk, and with better results than most outdoor aerials give. You simply screw a Dubilier Ducon into any lamp socket, and connect it with the antenna binding post of your set. You will find that it increases selectivity—especially in crowded neighborhoods, and will reduce “‘stat- ic” in the summertime. Try a Dubilier Ducon on your set tonight. They are sold by all good dealers on five days’ trial for $1.50. © Dubilier CONDENSER AND RADIO CORPORATION 4377 Bronx Bivd., New York, N.Y. POPULAR SCIENCE MONTHLY [ae Islonne Workshop | Automatic Block System (Continued from page 70) be hidden away under some of the scenery if you want to keep it out of sight. The wooden arm is % in. square and 5 in. long. A hole for a thin 114-in. wood screw. is bored through one end of the arm. Make the hole big enough so that the screw will be a loose fit. Mount the arm on the base with one fiber washer between the arm and the base and an- other under the screw head. Adjusting the screw will regulate the amount of effort needed to move the arm. The lower washer also supports the arm sufficiently far above the base so that you can wind on some soft iron wire to act as an armature and still have the arm swing clear. OU will need soft iron wire of any gage not larger than No. 14 to make the armature on the moving arm and for the cores of the two electric magnets. If you have wire of approximately No. 14 gage, use between 15 and 20 turns on the movable arm or an equivalent bulk of smaller wire. The next step is to construct the mag- nets. Use enough pieces 24% in. long to make a core about 1 in. in diameter and wind with one layer of friction_ tape. Then wind on three or four smooth layers of No. 22 cotton or silk insulated wire. The number of turns and the size of wire can be varied within rather wide limits and the device still will work perfectly. Avoid many turns of very fine wire, how- ever, if you intend to use the device on alternating current, as the increase in the number of turns will make the magnet weaker instead of stronger. After you have wound the wire on each magnet, put on a couple of layers of friction tape to protect the insulation. Then you can mount them on the base as shown in Fig. 2. They are clamped down by means of wire straps with a small wood screw through a loop bent in each end of each strap. This construction will allow you to change the position of each magnet with relation to the armature and so adjust the motion of the armature. LAMP the magnets loosely in place as the final adjustment must be made under operating conditions. Now fit to the free end of the arm two sheet brass contacts as shown in Figs. 2 and 3, and mount on the base two brass contacts so placed that they will engage with the contacts on the arm. The sim- plest way to mount each of the contacts on the base is by means of a pair of round-headed wood screws as shown in Fig. 2. Don’t waste any time now in adjusting the spacing of the contacts as this, also, must be done after the system is set up and the current is turned on. You can, however, make sure that the contact on the arm is bent so that it will slide over the edge of the contact on the base in each case. Next mount six screws on the front edge of the base to act as binding posts and you are ready to begin the installa- tion and wiring. (Continued on page 107) © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. OSIRIS IRI ee x SHOCK PROOF DUSTPROOF MOISTURE PROOF CASE 17 JEWEL SHOCKPROOF MOVEMENT THIN SLENDER HUGS THE wrisr GROOVED Stem EASY GRIP SECOND HAND FoR TIMING PURPOSES A TRIUMPH! Illinois ‘“‘Sportsman’’—the 2-in.4 Strap Watch—for DRESS-Wear; for SPORTS-Wear. Has remarkable SHOCK-PROOF movement, double strength mainspring, steel wheels, plates, escapement, secret process tempered. Genuine Ruby Jewels—not 7 of 15—but 17 jewels for PRECISION! Created by ILLL NOIS WATCH CO., Springfield, Illinois. The U. §, Government, during the World War, requested their entire output of Military Watches because they were conceded best. A Glorious Xmas Gift! BUSINESS MEN, Professional Men, Executives, Sportsmen _are ASTOUNDED at its Splendid Performance under action! Terrific drives down the fairway, smashes on the tennis courts; winter sports; motoring, hunting, intense heat or cold do not affect its timekeeping! It’s SHOCK-PROOF! WEATH.- ER-PROOF! Enthusiastic owners praise its ACCURACY and RICH BEAUTY! Case is DUST-PROOF! MOISTURE. PROOF! Green or White Gold Filled. Radium dial GLOW§ time BRIGHTLY in Darkness! For Red-blooded Men! $50-List. Our price for LIMITED TIME $338 to advertise our Direct-to-User value We ask for NO Mo Our lam j adeances NOTHING on De e } Dighrent she persons (or 10 Damn ible persons for 10 Days trial ABSOLUTELY FREE! If pleased you may pay on Budget Plan:— $6 MONTHLY or, if you wish to pay cash within 10 DAYS, deduct $2.70 and send Check or Money $31 25 Order for $31.25. Otherwise re- turn it. Send NO money. Pay NOTHING on Delivery! Order NOW at this Special Price! Dr a ee ee a oe ee en ee ee ee SEAVER-WILLIAMS CO. Importers, Exporters, National Mail-Order House “2 Generations of Honorable Dealings” ! | 365 WASHINGTON STREET, BOSTON, MASS. I Sole Distributors of SHOCK- PROOF ‘Sportsman.’ Gentlemen:—Please send $33.95 Illinois ‘“‘Sports- | man” watch for 10 days’ FREE Trial on the above plan. (JGreen Gold Case. [> White Gold Case. (Check color.) ee eee ee ee | Clip and m~‘l this Adv. NOW to insure XMAS Delivery! # ge eg a Please tell us something about yourself, Trade reference pre- . e will appreciate and respect the, snormares . ‘op. Serred. THANK YOU Beh 13-38 | World Radio Storage “B” Battery 12 Cell—24 Volt Proved value. Thousands of users find reception almost magical. Clear, true power—instantly and unendingly. Wise economy. Sturdy construction—Solid Rubber Case protec tion. Recharged for almost nothing. Endorsed and listed a8 standard by famous Radio institutions including Pop. ratories, Pop. Sci. Inst. Standards, Radio News Lab Lefax, Inc., and other Radio authorities. What more besaid? Extra Offer: 4 Batteries in series (96 volts) ~_ wanted and we will Send No Money og roruer js zoceived, &7 Fa .O.D. after examini atteries. jiscount yt with, order. "Remember—you save! 50% on World Batteries. ERY. COMPA! Dept.80 Chicago, IIL Makers of the Famous World Radio **A’’ Storage Battery ices: 6-volt, 100 A . $10.00; 120 Amp. $12.00; 140 Amp. $13.00. Prices: 6-volt, 100 Amn ced wiih Solid Rubber Cave. radio dials at 288.8 meters for the World Storage Bat- Son Station WSEG.- Variety-NewTalent-Always Interesting, JERRY SULLIVAN— Director and Announcer —‘*Chi-CAW-go su —_ =e Oe oT = FO

Page 105

a OMe Workshop | ' Automatic Block System (Continued from page 106) The electromagnetic switch can be placed wherever convenient, although it is de- sirable to have it near the signal tower to cut: down the amount of wire needed to make connections. ‘The tower for the red and green lights can be made up in any desired form. In the experimental installation shown in the illustration, an old burned-out thermostatic control | tower was used after all the mechanism had been removed except the red and een lights. eT he Biion of the third rail that car- ries the current to the collector rollers on the locomotives (marked O in the dia- m) must be insulated at both ends by pulling out the connecting pins. The in- sulated portion should be about three or four track sections in length or long enough so when the current is cut off from this part of the track the oncoming train will not coast clear beyond it. Now study Fig. 4, which shows the way to bend the heavy wire contacts A and B. SSP rSrer & fl ~~ BONE OF THE TRACK CONTACTS, A AND B + | ets! R aPeFeess ~#——— | Yn" sl | L aos Fig. 4. Electric locomotives are made with double roller collectors. One roller contacts with wire; the other rests on the third rail These should be fastened to the floor or a light wooden board under the track in such a way that the upper straight sec- tion of each contact will be parallel to the third rail and about % in. from it. The straight sections of the contacts, which should be slightly higher than the third rail, must not touch either the third rail or the outside rails. Use ordinary bell wire for all connec- tions. No. 1 binding post (Fig. 3) is connected to one wire from each magnet, to one terminal of each of two lights and to the outside track rail at the nearest point. The remaining wire from magnet D is connected to binding post No. 2 and track contact A also is connected to this binding post. Contact Y is connected to binding post No. 3, and the remaining terminal of the green light and the in- sulated third rail O also are connected to this binding post. Connect contact X and the remaining terminal of the red light to binding post No. 4. Connect the remaining wire from magnet C and the track contact B to binding post No. 5. Then run a flexible wire from both of the contacts on the movable arm to binding post No. 6 and also connect this binding post to the third rail at any point except section O. This completes the installation and wiring and you are ready for a trial run and the adjustment (Continued on page 108) teas uence aaa sank gutaeat sip ak Paes Far sersa ve 8 UF POPULAR SCIENCE MONTHLY 107 The phone never rings for Jim —perhaps it’s comedones* Time after time Jim answers the phone only to say, “Here, Walter, it’s for you.” And that’s the way it is with everything so far as Jim is concerned. He’s usually neglected —seldom counted in—often counted out. He never thought to blame it all on comedones. A great many young men suffer from comedones—commonly called blackheads. Skin can’t be clean-look- ing, fresh, wholesome, if these dis- figuring formations are present. What’s more, you may not even be conscious of comedones. But your friends notice them. You may wonder why invitations become fewer—why friends—girls in particular—seem to avoid you. You may never guess. Perhaps it’s comedones. Pompeian Massage Cream helps you overcome comedones. It gives you a clean, clear, ruddy complexion. It SEND FOR 10-DAY TRIAL TUBE For 10c we will send a special trial tube containing sufficient cream for many de- lightful massages. Positively only one jtrial tube to a family on this exceptional offer. Use this cou- pon now. tS} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. gets into the pores where comedones form, rolls out all dirt and oily secre- tions, and stimulates a healthy circu- lation, keeping skin clean, pores open. Try this treatment After you shave, spread Pompeian Mas- . sage Cream generously overyour face — and rub, Continue to rub until the cream rolis out. Note how dark the cream looks. That’s the dirt that was in your pores. Don’t let comedones form. Use Pompeian Massage Cream every day—especially when social or business en- gagements demand that you look your best. It means a healthy, whole- some skin. It means more joy in living. *WHAT ARE COMEDONES? (pronounced ci m'é-dones) Dictionary definition: A small plug or mass occluding the excretory duct of a sebaceous gland, occurring frequently upon the face, especially the —_ It is often called black- ead. Use at Home after Shaving To get full pleasure and benefit, use Pompeian Massage Cream regularly at home after shaving. Your face will feel and look like a mil- lion dollars. 60¢ jar Tear off, sign and send at all drug stores. The Pompeian Laboratories, Dept. 54 Cleveland, Ohio Gentlemen: I enclose 10c (a dime, coin preferred) for a special trial tube of Pompeian massage cream. Street Fe ECT EE ETO OC ee GHG sc cc ccceceuec es das wwe Ceoeeel State. ...ee

Page 106

-” the line is asy with this chisel-edge claw Hammer ., ERE is something new in ham- mers. The one-pound head of forged steel carefully tempered has a chisel-edge on the end of the claws. It is perfectly balanced and the two extra side claws makes it ible to pull nails in close corners or next to the wall. The distinct curve to the claws creates a fulcrum that makes it possible to pull out large nails with one pull. The chisel-edge claw hammer has been tested and approved by the Popular Science Institute of Standards. Every man doin, ing carpentry wor or odd jobs around the house will find hundreds of uses for the three-in- one hammer. It will do everything any other hammer ill do. Besides it can be used as a chisel and it will get at nails that other hammers won’t reach. The price for this new hammer is only $2.00. If your hardware dealer hasn’t the chisel- edge claw hammer in stock write to us send- ing his name and we will fill your order direct Chisel-Edge Claw Hammer Com ey H. A. Ayvad Hoboken, N CHISEL-EDGE CLAW HAMMER POPULAR SCIENCE MONTHLY Vie ome Workshop | Automatic Block System (Continued from page 107) of the positions of the magnets and the contacts X and Y. Assuming that the arm is to the right so that contact Y is closed, you will note that the green light will be lighted and current will be supplied to section O of the third rail so that a train traveling in the direction of the arrow will run across section O without stopping. Just after it has left section O, the collector roller on the locomotive will strike contact B, and the current will flow through the windings of magnet C. The movable arm will be pulled over to break contact Y and close contact X. This will result in shutting off the green light and turning on the red light and at the same time the cur- rent to third rail section O will be cut off. A train following the first one will there- fore stop when it runs onto section O, and it will remain standing in front of the red light in the signal tower until the first train has traveled as far as contact A, when current will flow through the wind- ings of magnet D. The movable arm will be pulled back into the first position, breaking contact X and again closing Y. The light will change from red to green and current will flow to third rail section O, whereupon the second train will start up and continue around the track. The distance between contacts A and B will depend on the length of the trains you are running and the size of your track layout. OU will find that the best adjust- ment for the magnets C and D and the contacts X and Y is such that the movable arm has the smallest possible movement that will completely break and make the contacts. If you get too little motion, both lights will have a tendency to stay lighted at the same time, and too great motion will prevent opera- tion. The friction on the movable arm should be adjusted by setting the screw so that there is just enough friction to keep the arm in the position to which it is moved by the pull of the magnets. If a single train is operated around the track, nothing happens except that the signal tower lights change from green to red and back again each time the train passes the contacts A and B. The sys- tem will operate only for trains traveling in the direction of the arrow. if you run a train in the opposite direction, it will stop itself in section O and will remain there until the movable arm is reset by hand. Block for Cracking Nuts { HEAVY hardwood block with sev- eral shallow holes bored in it is a help in cracking any large quantity of hard-shell nuts. There should be a hole for butternuts, another for walnuts, and so on; in each instance the nut should project about one-third its length above the surface of the block. A sharp rap with a hammer on the end of the nut cracks the shell without scattering the pieces. © This seal on a radio, tool or oi] burner‘advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. December, 1926 . i Would you like to own this combination end table and book trough? Bought in a store this end table would cost $20 to $25. If you make it yourself it wil] cost you only $5 or so for the hardwood, and the finishing materials. If you can use a hammer and saw you can easily make this handy table from Home Workshop Blueprint No. 3 which will be sent on receipt of 25c. Blueprints mailed the day order is received, POPULAR SCIENCE MONTHLY 250 Fourth Avenue New York AERTS TT Uses graphite disc resistors which are noiseless and not affected by atmos- pheric conditions. ®, Metal parts are nickel "se plated. One hole mounting. Finish /- weak knob match Bradleystat. Made in 200 and 400 ohm * ratings. E 5) s - Allred Ca ¥ 5, Electric Controlling Apparatus t 293Greenfield Avenue Milwaukee, Wis, F] eee es st “DON'T SHOUT” “I hear you. I can 3 now as well as any body. ?’ With THE MORLEY PHONE. I've a pair in my ears now, but they are invisible. I would not know Ihad them in, myself, only that I hear ‘all right.” The Morley Phone for the DEAF is to the ears what glasses are to the eyes. Invisible, “ Byaniges oy = nantes armless. n can it it ver one hundred tho palm in wy eg oo Py THE MORLEY CO., Dept. 797, 10S. 18th Street, Philadelphia 84 Illustrated Pages of Radio Bargains! Write for Catalog Today RANDOLPH RA 0 CO FE. SPORT BODIES for FORDS at FACTORY PRICES! This Model pa 83. 50 Write for Booklet d: 10 Showing Other Models. SPORT FACTORIES, Aurora, Illinois

Page 107

1926 POPULAR SCIENCE MONTHLY Galion Workshop | SSS This Peanut Duck Walks Downhill By Georce D. Huco NE sunny double-header afternoon I searched between innings in my bag of peanuts for those of a certain shape and size and, as the slender result of my watch- fulness, carried home half a dozen selected roasts in my vest pocket. These were for the construction of a walking duck. A duck was wanted (Fig. 1) that would waddle realistically down an incline— Fig. 1. The [7 duck isgoing for his walk Fig. 2. The hobbyhorse walking boy something to amuse the kiddies and, pos- sibly, those grown-ups who might happen to see the toy in action. There is on the market a very popular wooden walking toy that works on an ingenious balancing principle, and it seemed that one might take the liberty of adapting this idea on a miniature scale toa peanut novelty. With peanuts of a promising shape at hand, few other materials were needed— a bit of 1% in. thick cardboard (wall- board), a couple of wire nails, and a feather plucked from an unsuspecting pillow. First to find the center of gravity of one of the peanuts! For a while I did not think that (Continued on page 110) Z 4 Np Gs J Ml dae} Sa ergy ] ey Fig. 3. A full size side view of the peanut duck and a section through the body and legs Bb CENTER OF y) GRAVITY Z 14 Z PIVOTED LEGS HY spend 7 to 10 cents per mile when the Har- ley-Davidson Single can be operated for one cent per mile? This new-type motorcycle of- fers you the lowest cost power travel. Itis even less expensive than riding on street cars! Convenient, too. Always ready. Needs only 2x8 ft. space — even the smallest garage has spare room for it. Travels 80 miles per gallon of gasoline. No radiator troubles. De- pendable, safe, comfortable, economical the year ‘round for business or pleasure. Your dealer offers a conven- ience Pay-As-You-Ride Plan and the price of the Single, complete with 3-speed trans- mission and full electric equipment, f. o. b. Milwaukee, is only $235 See your dealer —and mail us the coupon. Hartey-Davipson Motor Co. Department P.S. Milwaukee, Wis. CThe HARLEY-DAVIDSON [Mewreke] Single The Harley-Davidson Single is easier to ride and control than a bicycle — safe and dependable. 5 y ae Mail Now/ . HARLEY-DAVIDSON MOTOR CO. ; Dept. P. S., Milwaukee, Wis. 1 OH Interested in your Single;send catalogand ’ my dealer’s name. : ’ C) Interested in your dealer proposition. Is : my territory open? H ' ® This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 108

POPULAR SCIENCE MONTHLY

In a Jitty-anywhere PUT UP-CHANGE- OR -— DOWN Satisfaction Guaranteed

Take your set anywhere—to demonstrate it, entertain friends or experiment—and in a few moments have a 100 per cent efficient OUTSIDE aerial on the job. Simply lead in the Reel Aerial Antenna under or over window or door, which

Makes “Reel” Christmas Gift!

may be closed tight without harm to wire. me Something different and new for your

radio friends. An aerial they can use at home, change about for testing and take with them on visits or trips! Note other uses illustrated. Mail coupon if dealer cannot supply you. HERE'S 100 feet of 4 in. wide FLAT bare, copper wire, with insulator on outer end, reeled up in a h A. _ ‘} tak led

Weighs only 21 ounces. Fits pocket. Unreel as long an aerial as desired, place case on or near set, insert plug on cable in cen- ter hole—attach other end Being flat, sm down, it is easily cleaned.

eel Aerial antenna has same induc- tance value as stranded copper wire. smooth and easy to take metal case, 414 in. diameter. UNSURPASSED PERMANENT AERIAL Reel

+ of cable to set—and tune

‘em in. Unused portion in

laboratories, schools, clubs trains, at fairs, etc. tape measure. <

For indoor aerials--Can be put up around walls or reeled out on floor. I, Size Actual Size of Case 414 in. Diameter theatres

MMMM SET ae You and This Machine Can Earn $300 Monthly Charge Batteries in 14 usual time at 14 cost. Small space re- ractically no invest- ment on your part. experience required. Pays for itself on easy monthly payments. 30 Days’ Free Trial. Write to- Hobart Brothers, Box THE ANTISEPTIC LI

Insulator PESTS SSRSRHREKEREHTSRSSRSSRRRERRREROCEEERRREREEeeeeeeeeeee = SEND NO MONEY, JUST MAIL COUPON case does not cause dead end losses. When through reel in like a No tangling. Provides 100 per cent efficient aerial in a few moments—any time, any place—indoors, outdoors. © DEALERS! JOBBERS! yf Write for attractive proposition. Sie Use Reel Aerials in making trial demonstrations. Sell Reel Aerials for indoor aerials, portable sets, to travelers and tour- ists, to experi- menters and _ to people desiring highly efficient permanent aerials.

Experimenters, Engineers! Attach Reel ports insulator tos

= z I je into und. Brir: antenna into house. Ry changing distance and Iocations ES ey oe Sees ict cd leaned one sadn: tse Aieeaarasaae eee

No special :180.N. UNION AV. HAWKEYE RADIO CO. Dept. 1612, Cedar Rapids, Iowa. Ship me—on_ your MONEY BACK GUARANTEE—one Reel Aerial C.O.D. I will pay postman $5 plus few cents postage (postage prepaid when money accompanies order).

= SAVE 1470 1%! Everything in Radio WRITE for CATALOG— FREE ‘RANDOLPH RADIO CORP. ept. CHICAGO, ILt,

A Quali

needed in thes Q1Sts

s | elon ae 2 829 E. Absor

ONLY wie SOUTH BEND LATHES ris} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. for so} SOUTH BEND LATHE

Countershaft Drive or Motor Drive ~ from Lamp oe ty Lathe Stripped for Small Shops This is our regular 9’’x214’ Quick Change Gear South Bend Bench Lathe, stripped of all extras not mall shop. It will handle a great va- .,riety of work with accuracy and pre- e cision. For example— With this lathe you can Turn Commutators, Undercut Mica, ‘Turn Pistons, Bore, Drill, Grind, File, Polish and use 6in. Chuck. Can also be fitted withour Draw-In Chuck At- ® tachment. Capacity ofcolletsOto}4”. Write for Free Bulletin No. 20-8 SOUTH BEND LATHE WORKS Madison St. South

Bend, Ind.

How to Square a Board with a Folding Rule HEN no square is at hand, a cap. penter’s two-foot folding rule may be used for drawing aline squarely ACTOss g board. Place the rule as illustrated, with

Squaring with a carpenter’s rule

THIS HALF OF RULE IS HELD STATIONARY —_es the legs separated any convenient dis. tance. Then hold the leg that touches BR in its place and swing the other leg from A as far as it will go. A line from A to € then will beat right angles to A B.—W. J.B. This Peanut Duck Walks (Continued from page 109) particular peanut had any, but it was there, after all. Slightly above that point a hole was drilled horizontally through the peanut for pivoting the legs. Through this hole the clavicle, if that’s the right name, was passed; it’s really a thin wire nail. On each end were mounted the round-bottomed legs, which were cut from the wallboard as shown. To form loose-tube spacers between them and the body, tiny strips of paper were coated with glue and wound around the nail. Beneath the body the feet were con- nected by means of another nail, placed at the point indicated in the side view (Fig. 3). This serves to lift the rear end of the body and causes it to roll forward upon its chest at a certain point in the duck’s progress, so that the legs will swing one step forward, ahead of the center of gravity. Then, as the feet make contact with the ground, the heavier tail end lowers itself, only to be lifted again by the connecting bar of the rolling feet. The movements continue with a smooth- ness and regularity that is astonishing. The chest and tail limit the stride, but to balance the duck properly, it was necessary to stick a heavy escutcheon pin in the tail end, as indicated in Fig. 3. The head and neck were cut from wall- board and glued in place. The joint was reinforced with a strip of paper. Finally the wing and tail feathers were added and the toy was painted. The other novelty, illustrated in Fig. 2, works on the same principle, but both body and legs were cut from wallboard. The pivot pin—just an ordinary sewing pin—has a bit of paper wrapped around it on each side of the body to serve as spac- ing sleeves similar to those used in the duck. A second pin passes through the boy’s feet and keeps them the proper distance apart. Another is pressed into the horse’s body, as shown, to regulate the stride; it stops the swing of the second pin at the completion of each step.

Page 109

UME LUMA gp S7OQB wer tS lS el i ee - — — =e SS CUE eee December, 1926 Dison Wormseciie How to Utilize a Cellar (Continued from page 82) and later potted to be transplanted into the open ground when the season is suit- able. Moreover, these plants can gradu- ally be made hardy so that they will not stop growing, as many greenhouse plants do when set in the open ground, and, therefore, they will be in bloom weeks before the ordinary hothouse-grown plants. This factor will be attractive to a gardener living in a locality where cold nights continue rather late in the spring. It is advisable for anyone who wishes to have a frame to fit up a small shop in the basement so that he may make his own trays. The writer has done all the work of building and maintaining his frame in his own little shop and is also able, be- cause of having the shop, to make many useful articles for the house and garden. Besides the economic side of this ven- ture—it insures a saving in florists’ bills— many enjoyable hours can be spent in this most wholesome recreation. The writer has found that his own little girl would rather spend her play hours with him in the basement than with her toys upstairs. A play nook in the cellar will be greatly enjoyed by any child. How I Remodeled the Cellar of an Old-Fashioned House By Mrs. A. E. H. Creswicke Barrie, Ont., Canada HE front cellar of our twelve-room house had never had the floor ce- mented. It was constantly damp and sometimes flooded in the spring. This had destroyed the lower bricks of four brick pillars supporting the center beam under the main floor and consequently the whole house had sunk in the center. To support the beams, I had a cement partition made, allowing for two door- ways. The floor of the whole cellar was tiled and drained into a trap. A partition cf plaster wallboard then was built to divide half the cellar in two. This gave a big laundry and a large storeroom, each with a window. The other half of the cellar, with the furnace in it, was objectionably dusty. Using 2 by 2 in. studding, I nailed a strip across the bottom of the main floor joists along one side of the furnace hole. Then, with a plumb bob, I found the exact line below it to lay another length on the floor. Between these I fitted 2 by 2 in. uprights, spacing them 16 in. from center to center. Two more studs were nailed to adjacent sides of the corner pieces to strengthen the corner and provide support for the wallboard. I nailed the wallboard on to make a close wall and thus confined the dust en- tirely to the furnace room and the 14-ton coal bin. Plaster of Paris mixed with flour paste so that it would not set quickly was used to fill all joints and cracks. The nailing was done with a shoemaker’s hammer, as it seemed to be well balanced and the big, flat head did not dinge the wallboard. The (Continued on page 118) POPULAR SCIENCE MONTHLY “A 7500 OHMS What a whale of a difference Bradleyohm-E For Bene service ~ quiring wide voltage control, Bradleyohm-E is essential. It is an oversize Bradleyohm with sufficient capacity to handle all normal B-elimina- tor requirements, Besure to ask for Bradleyohm-Ein the checkered carton. Your dealer can get them for you. Bradleyunit-A This solid, molded, fixed resistor has no glass or her- metic sealing in its construc- tion. Itisa solid unit with silver-plated end caps that are not affected by tempera- ture, moisture and age. By all means, use Bradleyunit-A when you need a fixed re- sistor. afew Bradleyohms make —in a B-Eliminator! AGAZINES and newspapers have been publishing circuits and instructions for assembling B-eliminators. Many types of kits have been used, but the outstanding feature has been the almost unanimous recommendation to use Bradleyohm-E for plate voltage control and Bradleyunit-A for the fixed resistor. The leading manufacturers of B-eliminators have. long since adopted Allen-Bradley variable and fixed resistors as standard equipment for their B-eliminators, In fact, the Bradleyohm-E has be- come almost as universally used in Raytheon tube B-eliminators as the Raytheon tube itself. The scientifically-treated graphite discs in these re- markable units have never been equaled for silent, stepless plate voltage control so essential ' for the satisfactory operation of a radio set with a B-eliminator. When you build your B-eliminator, always insist that Bradleyohm-E and Bradleyunit-A are in- cluded with kit. You then will be assured of per- fect voltage control. Send for folder“How to Build aB-eliminator” describing seven popular hookups. ALLEN-BRADLEY CO. 293 Greenfield Ave. =: Milwaukee, Wis. en-Bradley Use ® Perfect Radio Devices . rIS] This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS See page 6. O

Page 110

POPULAR SCIENCE MONTHLY

We will send this famous watch, express pre- paid, for you to examine, to inspect, to admire * to approve without one ny advance pay ment. Examine the watch and be convinced it’s the best watch buy you ever saw. Just a ent down, the balance easy You use the watch while paying for it SAVE 4 TO 12 OF YOUR MONEY By purchasing this Famous Santa Fe Special Watch, not only are you saving money from the present-day prices of watches, but you can still secure the “Santa Fe Special’ Watch, at the same low prices and terms that have made our watches famous. LADIES’ WRIST WATCHES Artistic, dependable ladies’ wrist watches— perfect timepieces, beautiful hand engraved cases in white or green gold. Send for New Watch Book and see the new shapes and de- signs. Sent on approval and sold on payments. JUST OUTI—NEW “SANTA FE” WATCH BOOK Send for our New Watch Book—just off the press. All the newest watch case designs in white or green gold, fancy shapes and thin mod- els are shown. Read our easy payment offer. Wear the watch 30 days FREE. Watch sent for your examination and approval without a y down. Nothing to risk. See the watch fore you buy. Write for New Book Today—It’s FREE. Select Your Watch NOW. SANTA FE WATCH COMPANY Dept. C-80, Thomas Bidg., Topeka, Kans. (Ho ne of the Great Santa Fe Railway.) See eee eee es eae eanaaans Santa Fe Watch Company Dept. C-80, Thomas Bidg., Topeka, Kans.

Please send prepaid and without obligation your New Watch Book Free, explaining your “No Money Down’’ Offer on the Santa Fe

Write Today for Our 84-Page Catalog of RADIO BARGAINS RANDOLPH RADIO: CORP. 180 'N.UNION AV. Dept:3.: CHICAGO, ILL.

G2 porine Wore sSIno,|

w I Remodeled a Cellar (Continued from page 111) sawing was done. with a pruning saw. The fine teeth I found good for starting a cut and the big teeth for doing the work quickly. For the door, I used a well-battened storm door. This left me with one quarter of the cellar still to be used. In that I installed a workshop, as I have been buying PopuLar ScrencE Monruty for some months and had become properly enthused with the desirability of having a place for tinker- ing. I made a workbench and on the back | board fastened a length of metal linoleum binding with large-headed roofing nails, to provide holders for some of the tools. A wooden vise was made, a metal vise purchased, and half of a butt hinge screwed to the bench near the left end of the top to form a stop for work being planed. A tea box filled with cigarette boxes makes a fine cabinet for small articles. Three raisin boxes, one above the other, with three pieces joining the sides so that they can be pulled out until all are uncovered, and a piece on the back for a leg, serve as a handy tool chest. In this little shop I have repaired sever- al chairs, done over a walnut table, a walnut sideboard and much other work. At present, having attended a motor mechanic’s class two nights a week for several months, I am getting my car into shape. Further plans for the cellar are to lay a floor of cork carpet 7 by 15 ft. in my work- shop and to build a great set of shelving. I also intend to cut off one end of the storeroom with another wallboard parti- tion and run the water service pipes back and forth many times across the ceiling before they go up to the taps. The fresh, cold water will keep the pipes cool and make it a cold storage room. It will have shelving added, of course, and hooks for provisions. ,

Dust Chute from Kitchen to Cellar Saves Footsteps By Irvin RITTENHOUSE Point Pleasant, N. J. ERE is an idea for utilizing a small space in a cellar that will save the housewife much work. I placed it in my house. A builder saw it. He has placed it in several houses he has since built. While most up-to-date housewives have a vacuum cleaner, brooms are still much used, especially in a kitchen. To eliminate the dustpan and receptacles for catching sweepings, cut an opening in the kitchen floor between two joists near the wall. Make a hinged drop door flush with the floor, witha flush ring pull. Place the hinged side, if possible, so near the wall that the door will not re- main open except when held up with one foot while the sweepings are being brushed into it. This will insure the drop always being closed when not in use. From the opening in the floor, build a_ straight, (Continued on page 113)

Your choice of world’s best types writers; late model,visible writer; 4 standard keyboard; 84 charac- Gs ters; 2-color ribbon. Low price. ' Famous N°5 <a 3 10 Underwood's) — ge Selsey vile wr = acters, back spacer, auto ribbon reverse, shift lock key, 2-color ribbon vnarginal stops, variable platen for writing on ruled paper. E tional ~ lag si Standard N'l0 os I Reminston'4) fe —_ ery latest model, contains 2- t—.--Ac Mn | color ribbon, full standard key- eA d, 84 characters, back spac- erand automatic ribbon reverse, & ain adapted for cor- A respondence, card writ- rete s | ing and statementwork, ¢ See ‘ at a big saving. : i Se: Famous Now Eats Royval'4 Up-to-dateimprovements: — = i key universal standar board, 84 characters, 2-color ribbon, back spacer, shift lock key,va | riable platen,inbuilt ta \ : easy and fast in operation, A vais bargain at this great saving, Visiple N° 8 LCSmith42 £0 Days’ Free Trial A) late models, completely rebuilt and refinished brand new. Guaranteed 10 years, Just send for our big Free catalog showing actual mac in full colors. Also our direct-to-you easy payment plan and special 10-day Free trial offer. No obligation. Write today, INTERNATIONAL TYPEWRITER EXCHANGE 184 West Lake Street Dept. 1238 Chicago, 1%

© This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

150,000 in daily | world wide use. DIRECT From Factory—Wholesale Prices—Easy Terms—No Interest. 57 years proves WITTE most durable, economical engine made—burns almost any kind of fuel — Semi-Steel Construc- tion—Valve-In-Head Motor—WICO Magneto— THROTTLING GOVERNOR-—Simple to run— Lifetime Guarantee—Excess Power. FREE CATALOG Describes New Improvements, New Lower Prices and Long Terms. Also Log Saws and Pumpers. Valuable Information. 3 Hour Shipping Service. WITTE ENGINE WORKS ullding, KANSAS CITY, MO. 2233 Fane ding Bldg. * PITTSBURGH, PA. 1221 Witte Bidg., FRANCISCO, CAL, 1% to 30 Horse Power.

SUB Cleveland Traffic Police use NOBURN.: Apply NOBURN--stay all day in rawest wind and shave with comfort at ale NOBURN absolutely makes you wind- burn proof and sunburn proof. At all A. G. Spalding & Bros. stores--or send $1 for bottle. Guaranteed--or money back. Sam Strong,505 Central Viaduct, Cleveland, O. Send for free copy of “The Invisible Mask”

BARRIER NeoburN.

—_— == A ef DH B&B ate oe OS ee

Page 111

Dust Chute to Cellar (Continued from page 112) F square chute of any light wood to reach almost down to the top of sugar or four barrel. Tack canvas or other cloth to the chute so that it will hang down over the barrel and prevent dust from getting into the cellar. To save stooping to lift the trap, a stick or rod with a hook attached to it may be kept hanging on the wall near by. How to Partition Off a Cold Room in a Cellar Corner By Dantet SMILEY, JR. Mohonk Lake, N. Y. ESIDES the regular coal bins, wood boxes, trash barrels and furnace, we have a carpenter’s bench and workshop, similar to that described in the April issue of PopuLaR ScrENcE Montuty. One of the more unusual features is a cold cellar, | a convenience almost always found in the } J J J SO Oa SP OE old country houses, but, I think, very seldom in modern houses. It is partitioned from the main cellar by 2 by 4 in. studding and regular wooden siding. The north corner is used so that the cement wall keeps it cool on : two sides. On the siding we placed or- dinary paper, but now one can get much better insulating material cheaply. This material also should be placed on the lower side of the first floor beams. The smaller the window or windows opening into the cold room, the better. The in- terior is whitewashed. Another feature of our cellar is a bathroom with a large shower bath for the use of workmen. Small Brooder House Built Outside Cellar Window By A. K. Kruse Marion, Kans. REVERSED three windows on one side of my cellar so that they swing outward and then from some old packing cases built a platform 3 by 9 ft., level with the windows. This was to serve as the floor of a small brooder house. Sides were erected and a hinged back put on. The floor was so arranged that it could be taken out for cleaning. In front of the windows I built a small pen. As the furnace room is always warm, this arrangement makes an ideal brooder house for small chicks. Builds a Band Saw Cheaply T MAY interest you to know that I have just completed one of the ball- bearing band saws designed by Mr. Ray F. Kuns and described in the February issue of PopuLarR Science’ MonrHuty. The saw works perfectly and was made at a cost of $23.77. A saw of the same size, if purchased in the ordinary way, costs $75.—H.S.M., Veazie, Me. POPULAR SCIENCE MONTHLY Aristocrat E-Z TOON Vernier Pointer No » \ anéven Greater 4 VALUE AN _ The. NEWe4ristocrat Vernier Port Dial HE new, improved Aristocrat Vernier Port Dial is one of the great dial values on the market. Despite its many outstanding advantages, the Aristocrat costs no more than ordinary vernier dials. If you really want a fine-looking, fine-tuning vernier dial, be sure you get the Aristocrat. Made of Bakelite. All mechanism and shaft ends are concealed. Calibra- tions appear in a beveled port with a peaked indicator that makes misreading impossible. Simple friction action is smooth, sure and quick. No gears, chains or cogs to backlash, wear out or get out of order. It may be installed in a few minutes. The famous Kurz-Kasch Split Bushing fits all condenser shafts—aligns rite, holds tite! You'll be surprised at the difference a set of Aristocrat Vernier Port Dials will make. In appearance your radio will look better than the season's prettiest models. And, due to the fine, 14 to 1 vernier ratio, you'll enjoy , This marvelous, recently com> better and clearer tones, more volume, and countless piled, 48-page Log Book (worth : ° rer bef 1 d $1) is given FREE with every Stations you've never before logged. set of three Aristocrat Vernier : o ee al Port Dials. Bound in beautiful, The Aristocrat Vernier Port Dial is supplied in three —— ne aro wr attractive finishes to match any radio—black with every United States and White markings, mahogany and walnut with gold Canadian Radiocast Station of markings. The price is $2 each—in the finish you record erode gy we Pu prefer. With a complete set of three Aristocrats, we call ‘letters, wavelengths and are making a special limited offer. We are giving away location. Also, includes the the beautiful, 48-page, authentic Log Book illustrated principal foreign ‘stations. Ask here. You'll appreciate this gift when you see it. Ask your dealer toshow youa copy. the better radio dealer ‘near you to show it to you, THE KURZ-KASCH COMPANY, DAYTON, OHIO Moulders of Plastics OFFICES: New York, Chicago, San Francisco, Los Angeles, Portland, Spokane, Denver, Toronto KURZ @® KASCH eAristocrat Dials and Knobs © This seal.on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. . See page 6.

Page 112

Wahl Fountain Pen Desk Sets from $7.50 to $30. Set illustrated, marble or glass base, two pens, $30.00 The Gifts

that Santa Claus would Choose Here are gifts that echo Merry Christmas all the year around ¥ Different, useful, lovely, and friendly ¥ ¥ Wahl Fountain Pen Desk Sets and Wahl-Ever- sharp Writing Sets ¥ ¥ The desk sets are something entirely new Vv A single gracefully ta- pered Wahl Fountain Pen, or a pair of them, perfectly balanced to the hand and set on a base of imported Italian Portoro Marble, Emeraline Glass, or Pearl Am- erith ¥ For the business man’s desk, let us suggest Portoro Mar- ble, jet black veined with tints from gray to gold, or finest Em- eraline Glass ¥ For the woman’s desk, Pearl Amerith, with its texture and sheen of mother-of- pearl, in Silver White, Rose Pink, Orchid, or Empyrean Blue ¥ v Ball and socket joints that permit turning the pens to any angle or elevation ¥ ¥ Wahl- Eversharp Writing Sets—a Wahl Pen nested in an attractive gift box with its companion Ever- sharp—are write gifts for every- body ¥ v¥ At Wahl-Eversharp counters everywhere. Wahl- Eversharp Writing Sets from $5.00 to $85.00. Set illustrated, gold-filled, $13.00

EVERS HARP WAHL PEN © 4936, The Wahl Company, Chicago he Wahi Company, Ltd., Toronto POPULAR SCIENCE MONTHLY

“<yppaupe Home

The Expert’s Way of Repairing a Shingled Roof By A. E. Ezine AVE you ever watched a carpenter neatly and speedily inlaying bright patches of new shingles in an old roof and said to yourself: “I wish I knew the trick of doing that so that I could fix those leaks in my own house’’? It isn’t really hard; you can do just as satisfactory, if not so rapid a job as an expert shingler. In repairing a roof it is of primary im- portance to ascertain the spots where the leaks originate. That sometimes is the most difficult part of the task. It often calls for careful sleuthing in the attic, with faint water marks for clues. A leak may be found quite a distance from the defacing rain stains on the ceil-

At the right is the DeHavil-

7 COUNTER FLASHING a 5 FLASHING Fig. 1. Completing repaits around a chim- ney by cementing counter flashing in place ing and walls of the room beneath. At times rain water will follow down a rafter or roof board a long way before leaking into the house. The attic right under the shingles affords the best information. When the leak or leaks have been traced, push a thin wire finishing nail up -through the shingles to indicate on the outside where the patching must be done. If it is not possible to examine the un- derside of the roof and the outside alone must be the guide, look the shingles over carefully just above where the leak shows in the room below. The shingles may appear to be sound there; in that case, search higher up wherever it seems likely that the rafters or boards may carry water down after it has penetrated be- neath the shingles. The first thing you will ask when you come to under- (Continued on page 115)

icin How Airplanes Fly! Build iu Own Flying ueaall he Learn the Principles of Aviation! Mot interesting thing you ever did; 4 fascinating, instructive hobby for cay man or boy. Shows you how real machines are constructed; how they fly. Ideal Models are accurate copies of real Airplanes; have parts and fittings like big machines, The are guaranteed to fly in the air when correctly constructed.

Above is the JN4D2 Curtiss Training Plane |

land World Flyer IDEAL Construction Outfits Make Model Airplane Building Easy! Outfits contain everything needed to build a fine Model Airplane, including complete plans, diagrams and instructions. Models are wondertul have rubber tired disc wheels, carved propeller, formed ribs, insignia and other ‘features of regular machines. Each outfit is complete: there is nothing more to buy. Pick the one you are goin to build and get started at once. Here are several popular? Models: ER North Pole 'Plane—3 ft. size Complete Construction Outfit.......... 8 .00 DeHavilland World Flyer—=3 ft. size Complete Construction Outfit.......... JN4D2 Curtiss Training Plane—3 ft. size Complete Construction Outfit......... NC4 Naval Seaplane—4'4 ft. size Complete Construction Outfit......... 00 Nieuport French Monoplane—3 ft. size Complete Construction Outfit . Bleriot or Taube Monoplanes—3 it. size Complete Construction Outfit, each. SPECIAL 6 FT. MODEL FOR MEN Fg the thing for the man who wants to build big model. Complete Construction outfit of the popular JN4D2 Curtiss Training Plane. 6 feet wing spread; one-seventh the size of the original. Complete Outfit includes everything requis? to construct and fly the model 5 .00 (Delivered by Express—charges colic’ Plans and Instructions for Building Model Airplanes Ideal Plans (Drawn to Scale) and Building- Fizing Instruc- tions show how to Build and Fly an accurate 3 Model of any of the following airplanes. (No ned Me included.) Send now for the set of — you want. FOKKER North Pole ’Pian PLANS AND 4 “ Type--Curtiss Training Pl jan INSTRUCTIONS ed tea Havilland Worid Flyer 5 Nese Seaplane |4 1/2 ft. size] c Bleriot, sen yaaa or Taube Monopiane Per eet Pos! Cecil Peoli Rac (8 Sets--$1.) 48 PAGE AIRPLANE CATALOG Gives full information on above Model Airplanes; 5c also lists hundreds of parts wo materials for Model builders. Send for it now IDEAL AEROPLANE & SUPPLY CO

163-165 Spring St. New York

“B POWER UNIT”

Delivers the proper voltage at all times with- out a trace of a hum. last as long as the best radio set. A full wave rectifier tube is used, no filament to burn out. Variable resistances control de- tector and amplifier voltages. 180 volt tap for power tubes. Plenty of current for any set on the market. Lower Price Higher Quality Positive Guarantee Sold direct from the factory to you and thru our authorized representativ es. Write for com- plete information. Unit shipped prepaid on receipt of $25.00, or C. O. D. for $25.00 plus transportation charges. EORGE ELECTRIC COMPANY 761 Comeeee. Ave., St. Paul, Minn. gents & Dealers wanted ! ? ! Sturdily constructed to,

Write = attractive agency proposition.

© This seal on a radio, tool or oil burner advertisement signifies the approval of the. INSTITUTE OF STANDARDS. See page 6.

Page 113

ste ith- | to. ent for on ity hru ym- lus ‘| from any retail lumber dealer. There are ‘overlap each other and shed the rain. POPULAR SCIENCE MONTHLY Repairing (Continued from page 114) take the repairs, is: “How shall I get up and work on the roof?” An iron roof hook, which goes over the ridge, may be obtained at many hardware stores. ‘This is fastened at the end of a light Jadder, which is pushed up on the roof until the hook drops over the ridge. In place of a ladder, a long board with evenly-spaced cleats may be used. Another method is to nail a sound 1 by @ in. shingle lath (these commonly come in lengths of 12, 14 and 16 ft.) on to the putts of the shingles so that an eightpenny nail will go through into the shingle lath below. Do not drive the nailheads right in; let the heads project so that they can be gripped and drawn out easily. Laths made in the form of a ladder, only wider than usual, may be used as illustrated in Fig. 1. Drive about four nails in the roof to hold this support in place. When these or any other nails are withdrawn from the roof, each of the holes should be stopped with roof cement. ——e ——| RAFTER i t — - |LATH YY ae a 7 YY), Vii, y “SEE W////; eo eT xix |x AT LEAST fetta 6 NAILS | aie ~-l. 4 Dt PASS THROUGH y et i EACH SHINGLE } i7_\\ a a ak ‘ mae] “ae T eo 1 ' 1 Fig. 2. How shingles are laid. Each nail ordinarily passes through three shingles If the nails have been driven into but not entirely through the shingle lath (and not right through the shingles into the attic) there is little danger that a leak will develop, even when no roofing cement is used, but it pays to be on the safe side. Shingles may be bought by the bundle between 200 and 250 shingles in a bundle. The lengths are uniform and should be 18 in. for roof shingles and 16 in. for wall shingles. The widths, however, are ran- |. dom and vary considerably. Shingle nails, preferably fourpenny in size, are used for fastening the shingles. Be sure to have on hand heavy tar paper, a tarpaulin or something of the kind to close up the opening in the roof quickly in case of a sudden storm. One of the simplest types of repair is when there is a crack through two shin- gles, one right above the other. This may be mended by pushing strips of painted roofing tin about 7 in. long up under the shingles. If the strips are put in the full distance, they will, in effect, If the shingles are too far gone and one or more new shingles must be inserted, remove the old shingles by splitting them up with a hatchet or chisel. Hammer them into small pieces and no trouble (Continued on page 116) will be found in f {© errors in building. good range and tone quality. - where. Six. amplification. 10c. Take Advantage of the New Power Tubes with the New Power-Six Kit The New Bremer-Tully Power-Six is a revision of the fa- mous Counterphase Circuit to take advantage of the latest improvements in tubes, resistances and parts. It is easier to build, balance and operate. Colored picture wiring diagrams, full size, leave no room for Simplicity with two dial control, selective, The P-6 kit includes the essential parts, totalling $45.10. Price of P-6 kit, $41.50, diagrams also sold separately, 90c. Better Tuning The 10th (Revised) Edition of Better Tuning is ready, 56 pages, the kind of information on radio you don’t find else- Instructions for changing Counterphase to Power- Full description of latter. Why the B-T Eliminator is different, the weak- ness of changing inductance with capacity, etc., etc. ~BREMER-TULLY MFG. CO. Treatise of new forms of Price, 520 S. CANAL ST. CHICAGO, ILL. 4 =aan | One Tube Radio Set Blueprint No. 41—Price, 25 cents Describes a simple, one-tube regenerative receiver of the fixed coil type. The regener- ation is controlled by a variable condenser and does not affect the wavelength adjust- ment. Quality of reproduction is excellent because no audio frequency current flows through the tickler coil. The coil is hand wound and the rest of the parts can be of any standard make. Four Tube Radio Receiver Blueprint No. 43—Price, 25 cents Describes a four-tube radio receiver con- sisting of one stage of radio frequency 1S} This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. MAKE YOUR OWN RADIO SET POPULAR SCIENCE MONTELY publishes reliable blueprints of radio sets. These sets give exc:llent results and can be made by anyone who is handy with tools. amplification, a regenerative detector, and two stages of transformer coupled audio amplification. It gives the greatest power for distance and volume that is obtainable from four tubes. Easy to build, uses any standard parts except the coils, which are simp!e to wind by hand. Two control tun- ing and regeneration does not affect wavelength adjustment. Three-Stage Amplifier Blueprint No. 42—Price, 25 cents Describes a three-stage audio amplifier to be added to one tube set of No. 41 to obtain loudspeaker results. Is equally useful with any other standard one-tube detector cir- cuit. Consists of one stage of transformer coupling, followed by two stages of resist- ance coupling. Volume control is simple and does not affect quality of reproduction. This blueprint does not describe a radio receiver —it is simply an audio amplifier to be used in connection with a one-tube radio re- ceiver. ° POPULAR SCIENCE MONTHLY, 250 Fourth Avenue, New. York City | } | } } ree rea AA AA

Page 114

Most Precious Christmas Gift, Say Pipe-Smokers Letters to us disclose that while a pipe- smoker will thank you politely for the pink necktie, fancy garters or useless novelty— what really delights his heart is a jar of good tobacco. That is why each year, more and more members of the Edgeworth Club make a ractice of distributing their favorite to- Ceoso among friends as a Christmas remembrance. The two favorite gift sizes of Edgeworth are the 16-ounce glass humidor jar and the 8-ounce tin. Both are provided at Christ- mas time with appropriate wrappings. Each size contains Edgeworth Ready- Rubbed, and each is packed in a good- : looking dec- orated gift carton print- ed in colors. Prices—$1.65 for the 16- ounce jar. The 8-ounce tins are 75c each. xe Please ask your tobacco dealer for the Edge- worth Christ- mas pack- ages. If he will not sup- ply you, we gladly offer the following service to you: Send us $1.65 for each 16-ounce jar, and 75c for each 8-ounce tin to be shipped, also a list of the names and addresses of those you wish to remember, with your personal greeting card for each friend. We will gladly attend to sending the Christmas Edgeworth to your friends, all delivery charges prepaid. Personal: Perhaps you yourself are not acquainted with geworth. If so, send your name and address to Larus & Brother Company. We shall be glad to send you free samples—generous helpings both of Edgeworth Plug Slice and Edgeworth Ready-Rubbed. Edgeworth is sold in various sizes. Both Edgeworth Plug Slice and Edgeworth Ready-Rubbed are packed in small, pocket- size packages, in handsome humidors, hold- ing a pound, and also in several handy in- between sizes. For the free samples, kindly address Larus & Brother Company, 10-X South 2lst Street, Richmond, Va. To Retail Tobacco Merchants: If your jobber cannot supply you with Edgeworth, rus & Brother Ficaieny will gladly send you prepaid by parcel post a one- or two- dozen carton of any size of Edgeworth Plug Slice or Edgeworth Ready-Rubbed for the same price you would pay the jobber. | your radio—tune in on WRVA, Richmond, Va: |» —the Edgeworth Station. Wave length 256 meters. POPULAR SCIENCE MONTHLY (Continued from page 115) taking them out quickly, bit by bit. Before the new shingles can be placed, however, the old nails must be removed. By examining Fig. 2, it will be seen that at least six nails have had a grip on each shingle; wide shingles have more. Four or more of these nails must be either broken off, bent over and flattened down, or drawn out. A tool used by slate roofers and known as a ripper will serve | to draw them out, no matter how far they are hidden, but it is not a tool easily obtained. Many carpenters also carry long, thin, narrow saws tempered to cut nails in repair jobs of all sorts, when these nails cannot be reached otherwise. HE work can be done with a thin pry-bar or a long, thin prying chisel. Drive it up against the nails to break them off, or bend them over and flatten them. In removing old shingles to make a patch, break out the top ones first, and the others will come easily. In breaking out the old shingles be sure to leave overlapping pieces so that no two of the new joints will come one above another. Fig. 1 shows the method of shingling and you can see just what to do, in any case, by observing the way the original shingles were laid. Begin at the bottom of the patch with the new shingles and use regular shingle nails for all the lower courses, but galva- nized or copper nails for surface nailing at the top. Some surface nailing must be done in repair work. Water often gets in around chimneys and walls because of rusty or defective flashings. The flashings are strips of tin, copper or other sheet metal which are laid against the brick and go under each shingle as it is placed. A penknife point pushed down on the flashing, especially if it is of painted tin, will often disclose that it has been nearly destroyed by rust. O MAKE a good repair, take up a narrow strip of shingles, put down new flashing, and replace the old shingles or put on new. ° The flashings, if of tin, should be well painted on both sides and allowed to dry before being used. They should be about 6 by 8 in. and are bent and applied as shown in Fig. 1. One is placed under the end shingle of each course as it is laid, so that the flashings overlap each other. Except on the chimney or wall side, they are hidden from view when laid. As shown in Fig. 1, the mortar is racked out from between the bricks where necessary and the counter flashing is turned in about 3 in. This metal is fastened in the joints with wall hooks or tenpenny nails and the cracks are filled with lead or elastic roofing cement. Standard roofing cements alone will oftén make a serviceable repair over im- perfect flashings at chimney or walls. They must be applied when the roof and walls are clean and dry. We now come to what is the most dif- ficult repair on a = (Continued on page 117) Make Things at Home| with Speed Way Shop! Free BluePrints Write for list of working blue-prints that we furnish free with each Speed Way shop. A compact and efficient electric work shop driven by the famous motor. Equipped with Eight Motor Driven Tools Gives you a complete Lathe, Bench Saw, Jig Saw, Portable Electric Hand Saw. A rtable or stationary power drill, equipped or buffing, grinding and cleaning. Attach the Speed Way Shop toany light socket and you have a completely equipped tool and machine shop Only $10.00 Down A small down payment, balance in easy monthly payments, puts one of these efficient machine Electro-MagneticToolCom pany 1830 S.52nd Ave.,Cicero, Ill. (AdjoiningChicago) Speed Way shops in your own home. 10 Days’ Free Trial Our free trial plan enables you to test out this shop in your own home. If it Ke less than we claim for it send it back. Make Things at Home with this shop—you can make attractive furniture, novelties, toys, radio work, bric-a-brac—countless other useful pieces. Don’t Delay— Write Today Write for full information on the Speed Way Shop. The shop is a money maker for the small job man and fun for the man who makes things at home. Write today, | Manager, Dept. 512: Please send me particulars | | about 10-day free trial, free blue-prints and $10 down payment. SRW AINE 5 bos 16,0 sno lays 2 ee yourself Cheer up—now you can mend metalware as easily and per- fectly as amechanic! All yon The pleasure of watching the Srighe, flowing solder, plug a ole or mend c break is only exceeded by the satisfaction of knowing you have donesomc- thing useful. Your hardware dealer can supply you with a can of this household solder. KESTER METAL MENDER CHICAGO SOLDER COMPANY | i i U.S.A. -325 * 4201-3 Wrightwood Ave. © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS... See page 6. Qe PIE ea a Es ll

Page 115

ne} rork Vay aw, ped the have shop thly hine bles oes r it can Ire, ork, her ion The for ces ay. Ly go) irs = im} ae vs SS ‘tadee B57 er Repairing a Shingled Roof (Continued from page 11 6) roof—when a leak is found down the valleys. A valley is an angle or gutter formed by the meeting of two roof slopes and usually is laid with a continuous one- piece strip of painted tin or other sheet metal from top to bottom. ; By pressing a sharp point against where shingles and flashing meet, you can tell if the metal has been eaten through. Re- move and carefully store the shingles if they are sound enough to be replaced. In any case, keep one to show the angle cut. Note, too, just how they were originally laid. Have a tinsmith lay a new flashing down the valley. A chalk line then may be drawn from top to bottom as a guide in re-laying the shingles so that a work- manlike job may be done. This work requires some care and patience and should not be attempted before practicing on straight patches. All other shingling repairs on roofs or walls can be accomplished by observing these suggestions and studying the method used in the old work that is to be replaced. THE average house in localities where the winters are severe is “good business” for the plumber and an annoy- ance to the householder unless the water pipes are well protected from Jack Frost. Wherever water pipes are exposed to the extreme cold, freezing is inevitable. My experience in having expensive repairs made during several winters led me to devise the following remedy, which cost less than a dollar for materials. I use it every winter and have yet to see it fail to safeguard the water pipes, although the outside temperature sometimes goes as low as twenty degrees below zero. At the point where the pipes are likely to freeze, which in my house was usually at the water meter, I built a housing of sheet metal so as to inclose as much of the piping as possible. A small gas plate burner was placed under the pipes; a good oil lamp would have served the same purpose. The gas plate is turned on only enough to keep it burning, yet this is sufficient to hold the water at a temper- ature above the freezing point. On espe- cially cold nights, as an additional pre- caution, the water is allowed to drip from Protecting Water Pipes | one or two faucets, so that it will be kept in motion.—H. J. Buake, M.D. 7 09 WHEN I was called Boots fi or upon to repair a chimney on a two- Roof Work story house not long ago, I found it dangerous to walk on the slanting roof with my leather-soled shoes. By cutting two pieces about 614 in. long from an old 4-in. inner tube and slipping them over my shoes, I was able to walk anywhere on the roof without slipping. If a pair of rubbers is at hand, they will serve the same purpose.—Mart J. HEFT. POPULAR SCIENCE MONTHLY 117 ho \3 TRADE GUIDES ee Audels Builders Guides are fully illustrated—ecasy to read and understand. Each set is a Good Trade Course for the apprentice—and a Reference for journeyman and master. Use coupon below for free examination. Audels Carpenters and Builders Guides—4 vols. $6 Inside information, Illustrated, for Carpenters, Builders, Joiners, Building Mechanics. 1600 pages; 3700 diagrams; flexible; pocket size. Short cut instructions, new methods, ideas, solutions, plans, systems—money saving suggestions. An easy progressive course for the apprentice. A practical daily vole ; { helper and Quick Reference for the master worker. A Helping Hand to oe 4 te, engl Moy Easier and Better Work and Better Pay. To get this aid for yourself, sim- : o ply fill in and mail the FREE COUPON below. Cx INSIDE TRADE INFORMATION ON: * 3 Rae. & Tools of The Trade—How to Use The Steel Square—Saw Filing—Join- cP 1 a —Hiow to Make Furniture—Carpenters and Builders Arithmetic— , to Read and Draw ee elie eg ogy peo hy to Figure Jobs—House and Roof Framing low to Lay Out Work—Foun- dations—Doors and Windows—Stairs—Millwork—How to Paint— and hundreds of other subjects,covering the entire tradewith pictures and explanations all easy to read and understand. * ‘‘Audels Carpenters and Builders Guides are just what every ‘7 man needs whofollows the building trade. He can learn more : i oo ? from your books than he would get a chance to learn in ys. 3 ee ba two years work.”’—J. A. Manning, Lockport, N. Y. Audels Plumbers and Steamfitters Guides—4 vols. A new set—just out! A practical, illustrated, Reference Library and Study-Course for Master Plumbers, Journeymen and Apprentice Steamfitters, Gas Fitters and Helpers, Sheet Metal Workers, j Draughtsmen, Master Builders, Engineers and all Building Trade Students. 1670 pages; 3642 diagrams; flexible; pocket size. Guide explains all the principles, advances and short cuts of the Plumbing and Heating trade. Contains instructions on how to figure and estimate jobs. Use FREE coupon below to examine, with- out obligation, this valuable work. INSIDETRADE INFORMATION ON: Plumbers Code—Physics—Materials and Tools of The Trade— Lead Work— Water Supply—Drainage— Rough Work—How to make Tests—How to Figure Jobs—Pipe Fitting and Bending—Heating—Venti gee reat os ee as— Steam—Sheet Metal Work—Smithing—Brazing— Motors, and hundreds of other subjects covering the plumbing trade. Each point clearly explained in i : , text and pictures that you can easily understand “Audels Guides are practical, easy to understand, and can be relied upon. They cover the entire field in plain language."'—W. F. Arminger, Annapolis, Md. Audels Masons and Builders Guides—4 vols. $6 A new, complete, illustrated trade reference library, for Bricklayers, Cement Workers, Plasterers, Tile Setters and Stone Masons. including a practical outline of Steel Construction. 1100 pages; 2067 vas mappa sncegi/\ diagrams; flexible; pocket Size. A practical Trade Assistant $6 J , explaining modern methods of masonry construction. Easy to ; fi. al Os, understand and apply. A reliable and authentic reference work al A) and study-course for Master Journeyman and Young Mechanic. a} ay Use FREE COUPON below and find out for yourself, without obligation, So of of as fs 4 3 whether this set will benefit you. INSIDE TRADE INFORMATION ON: Brick Work— How to Lay Brick— Various Bonds and Designs— Brick Foundations— Arches— How to Set Tile— How to Figure Jobs— Concrete Work— Mixing— How to Place Forms— Rein- forced Work— Stucco— How to Plaster on Different Surfaces— Stone Masonry— How to Read Blue Prints— Complete Outline of Steel Construction— and hundreds of other subjects with diagrams, pictures, text— easy to read and understand. ‘‘Audels Masons Guides are the bestbooks to be had on the subject.” —W. A. Sonnet, Corliss Sta., Pa. Audels Handy Book of Electricity—1 vol. Complete in one Audels Handy Book of Practical Electricity, Mlustrated, is a handy,redleather Ready Reference and Study Course in one pocket-size, leather 4, bound volume bound book. Every engineer, electrician, mechanic and student ‘y fy aera will find in this up-to-date Guide the KEY to a practical un- : derstanding of Electricity. 1040 pages; 2600 diagrams. A reliable authority and Helper—easy to understand. _ INSIDE TRADE INFORMATION: The entire electrical field is covered in this one volume. Here are some of the chapter headings: : Wiring Diagrams—Caliculations—Machine Sketches—Main- ‘ve tenance and Repair—Radio—Armature Winding—Power Wiring—Storage Batteries—A. C. Motors and haere ha Cc. Motors and Wiring—Telephone—Telegraph—ignition—Generators—with Ready Reference Index which gives a quick answer to every problem. $4 To Barn Ge a vim e ee Sey More— ILE Please mail me for free examination the books marked (x) below. If I find COUPON them satisfactory, I agree to mail $1 in 7 days, on each set ordered, and to further mail $1 monthly oneach set until I have paid the purchase price. Li 4 CARPENTERS 4 PLUMBERS GUIDES $6 GUIDES $6 OUR GUARANTEE Cl] éoreere 1 ELECTRICIANS GUIDES $6 HANDY BOOK $4 Examine any book published by us without charge. = if you like it, keep it. If not, send it back. Pay us = Oe ee a ie only if you are satisfied. No charge if you are not. : ye 1+. i oe re ke ae THEO. AUDEL & CO. occupation ) Learn More Your Big Opportunity for Advancement Be a GOOD mechanic. It’s more satis- fying. It insures you against unem- = ployment. Learn all about your trade by easy reading of these Builders Guides. 65 W. 23rd St., NEW YORK, N.Y. = EMPLOVED BV.............---..0.5-5-. 12T34 IS} This scal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 116

118 ASK .. ANY .. RADIO. . ENGINEER of Burgess Radio Batteries They Flew Over the North Pole with Byrd N May 9,-1926, history was made: American history; World history; undying history. Lieut. Commander Byrd, in his fearless 1500-mile flight across the top of the world, adds another thrilling triumph to the long, proud list of American achievements. Radio went along, for radio has become vital to the lives and success of explorers and adven- turers, Burgess Batteries went along, sharing the fate—sharing the hardships and the glory of Commander Byrd, the Detroit Artic Expedition, and Capt. Donald MacMillan. It is eminently significant that in these glorious triumphs of American courage and American equipment where the test of men and their tools was the test of the survival of the fittest, that the standard products of the Burgess Battery Company were selected, used and “carried on” under extreme and unprezedented conditions. Burcess BATTERY CoMPANY GENERAL SALES OFFICES: CHICAGO Canadian Factories and Offices: Niagara Falls and Winnipeg =.© et, an if | on BURGESS RADIO BATTERIES POPULAR SCIENCE MONTHLY No aN can better please the house- Full Length Mirror wife than by in- stalling a full length mirror ona closet or bathroom door. If the door is of the single panel type, merely get a mirror that will fit into the recess and go flat against the panel. A panel molding is applied to hold the full length mirror in place on the door Miter around the edges a narrow panel molding. The type of molding will depend somewhat upon the style and construction of the door. Your lumber dealer will have something that will serve. Before applying the molding, paint the outside surface and also the side that is to go against the glass. On doors of other types, such as those having five panels, lay out pencil lines on the stiles and on the upper and lower rails as a guide for applying a rabbeted mold- ing. Nail on-the lower piece and one side, set the mirror in place and put on the other two strips.—Epwin M. Love. Draft Screen for Bath a* bathroom so that the tub is located under the window. On windy nights a cold breeze is apt to blow through the cracks on the bather. To shut out this draft in one such bathroom, a remov- able screen was made of closely woven canvas. After the piece had been hemmed, four tent or awning ButILpEers have a habit of planning TENT CLOTH grommets were riveted in the CURTAIN ends. These were hooked on brass headed nails driven in the edge of the windowcasing.— C. D. Paterson. Canvas screen designed for shutting off drafts WHEN enamel or varnish sags and runs unduly, it is often because the surface has not been cleansed of grease. © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Harmonicas Make a Happy Christmas Everyone delights in receiving a musical instrument that he can play; and anyone can play a Hohner Harmonica. If you want to give happiness with your gifts at Christmas-time give Hohner Har. monicas—a happy thought! Leading dealers everywhere carry the com plete line of Hohner Harmonicas—50¢, and up. The Free Instruction Book, con favorite musical selections arranged font harmonica, is available at dealers or direct, M. Hohner, Inc., Dept. 182, 114 East 16th St., New York. TYPE WRITE Letters, lessons, a | gees — oe oe on os a : a CLIP THIS NOW! pre a on this U: ood! Totall: t: | fioe-year guara: brews LA. typet seve pew piaken: new ay usb: anda | FREE BOOK! jains hele erlang ctr swer, instructions free in touch y+ at a ‘CHIcaGo. we BO Ee LD. Shipman-Ward Mfg. Co., 2149 Shipman Bldg Puts the OTTAWA 3 Working For You Greatest LOG SAW Offer Se ee ee ee Pay See recta oe eae San Total Over and big DREE book. OTTAWA ones Bieet @ ca ay mete 1801-W Weed Stree ttawa, Kan. 1801-W Magee Bidg., Pittsburgh, Paw - —J ~*~ eee mee

Page 117

FU 88 ARF oy me ect, vast

ET the correct speéd and feed and let the machine do the hard work while you do the head work. Memory is a big asset to a man, but it is sometimes better to forget than to remember. It is unnecessary to use back gears when turning or milling brass, copper and other soft metals, except perhaps for the removal of hard scale on brass castings; after the scale is removed, finish the job on open belt speeds. Every man should try to give himself a square deal—and give the shop one, too! If you were caught on the roof of a burning building, would you jump down or try to find a safer way? Then why jump to conclusions when you have a tough shop problem to solve? It is well to be sure that you are right, but it is not right to think that every- body else is wrong. When filing work keep your file clean; if an ordinary file brush will not readily remove the small bits of metal that stick in the teeth, a piece of flat copper or brass will take them off. Get down to business and get ahead of your luck. _ There is no safe way to cover up or disguise a ‘‘bull’’; lives are often endangered by faulty construction. | Small Roller Makes It Easy . to Move Long Pipes TOCK-ROOM men in shops and supply stores will appreciate the roller shown. It is for moving pipes about, espe- cially in narrow aisles. It is mere- ly an iron roller held in a sheet- iron frame. It is inserted in the end of the pipe, which is pushed along smoothly over the floor instead of being dragged. — Norman Moore.

End of the pipe with the roller inserted

Ir orTEN occurs that a piece of work is pulled off a demagnetizer and the current is left on unnoticed. This is harmful and costly. It can be avoided by installing a pilot warning light on the wall between the switch and me instrument.—H. J.C.

a This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. POPULAR SCIENCE MONTHLY

em Sign off “le fo sweet dreams You enjoy radio like a gentleman—if you can get the best out of your set and forget all worry and bother. That’s your happy frame of mind when you keep your batteries full of pep with a Rectigon. The most absent-minded dial-twister snaps on a Rectigon without a qualm. What if you do tune in while you’re still charging your battery? There’s no harm done, not the slightest. What if the current does go wrong in the dead of night? Your batteries will not be discharged with a Rectigon attached. when you keep power in your set with not _, The Westinghouse —not a bit of fuss. Not even a murmur that would disturb ©, 1926 ’ ectigon «2: the mildest slumber. No Acids, No Chemicals —no moving parts—nothing tospillor burn. No muss; no .¢ worty. You'll havenospoiled terminals. Saves service station bother. Spares inter- ruptions caused by absent batteries.

Charges Both ‘‘A’’ and “‘B’’ Batteries —Keeps both packed with power. Bulb i bie used for battery im ing and is en- closed, like all other parts, in metal, safe from accident. (Rectigon charges automobile batteries, too.)

THE RECTIGON i is a superb Westinghouse product. Things you can’tsee, like extra heavy insulation, things you can see, like the durably enameled case—all are of highest quality. Westinghouse also manufactures a complete line of radio instruments, and Micarta panels and tubes. WESTINGHOUSE ELECTRIC & MANUFACTURING CO. Tune in on KDKA - KYW - WBZ - KFKX No Storage Battery Radio is Complete Without a Rectigon

Practical, Desirable CHRISTMAS GIFTS! Gerstner TOOL CHESTS are ideal. Get our cat- alog and select your own. A postal brings it. H. GERSTNER & SONS 536 Columbia St., Dayton, 0. GEARS All Kinds-Small The most amy (Ay made and prices reasonable e@ carry a complete °S line of gears in stock for immediate ‘S shipment. Can ee uote on ay iQ gears rs of all kinds. nd us your in quiries. Write for Catalogue 214 CHICAGO STOCK GEAR WORKS 105 South Jefferson Street Chicago

NEW SPORS RED OR GREEN PEN. MANY MAKE $10 DAILY EASILY AGENTS G5e SEAS FOR $1.25 WRITE LIME A SAMPLE € IDEAL XMAS GIFT $7 PEN IMPROVED POINT

New and Unusual Mail Order Distributing Plans and Large Wholesale Specialty Catalog, showing best sellers from all parts of the world. F. SPORS CoO., 189 4th St.,

Se eee LESUEUR CENTER, MINN.

Page 118

Chemist! Have Days of Real Fun and Learn the Wonders of Chemistry HAYe more fun than you ever had before! Make soap, inks, dyes and paints; test water, food, soil and metals; do lots of other wonderful chemical experiments and learn the principles of chem- ical science. Perform mystifying | tricks of chemical magic and astonish your friends; experiment with chemical sorcery and produce § many magical changes. It’s fine § fun for any boy; keeps you inter- § ested and teaches you facts about § the wonders of chemistry. You can do it all with GiEMCRAFD |; THE CHEMICAL OUTFIT. the Boy’s Own Laboratory! | Get Chemcraft for Christmas! The original of all chemistry sets, and the most scientific set on the mar- ket. Contains more and better experiments, more chemicals and apparatus. Teaches reliable chem- ical science; anybody who experi- § ments with Chemcraft knows more § ‘about Chemistry than most people. fa) Each outfit is complete and con- fq tains safe chemicals, all necessary fH) apparatus and a big Manual of § Instruction and Experiments. ile) Sold in all Good Toy Stores No. 0—75c; No. 1—$1.50; No. 2—$2.50 No. 3—$5.00; and No. 4—$10.00 (West of Denver, Colo. and in Canada, add 10 per cent) fz. Don’t accept anything but Chemcraft; §& insist upon having the best outfit. If more f convenient, we will send your set prepaid, upon receipt of price. Big Book Free! if The Chemcraft Chemist Club Magazine; i prepared specially for boys who want to — more about chemistry. Full of stories, fine experiments and club news. It’s free—just write for it. (VT0UONYOUYNROOO YOUN AUUELAA ESTO UU RRR NN PER fA NLA acer JUNIOR A fine set for boys who want to try chemistry. You can make ink, dye cloth, test water and do lots of magical tricks. Always sold for fifty cents, but if you send us the _. names and addresses of five boys who haven't Chemcraft, we will send you Chem- 25¢ eraft Junior for o The Porter Chemical Co 115 Sum- mit Ave., Hagers- town, UTC POPULAR SCIENCE MONTHLY ‘PANTOGRAPH’ CARD “Pantograph” Card Aids in Milling By Henry Simon ILLING a rod to an odd cross sec- tion, such as shown below, is not so hard when the proper equipment is at hand to do it with, but presents great difficulties when, as is more often the case, it must be done on a plain miller with only an ordinary vise. To hold several surfaces parallel or at specified angles to each other while staying, at the same time, within specified dimensions, is extremely hard. That is because there is no good way of checking accurately the position of the surfaces as the work progresses. A satisfactory method of solving this problem is to use a modified pantograph method. On a disk of stiff bristol board, the cross section is drawn carefully on a large scale, say ten to one. The disk is fastened directly to the end of the rod to MILLED END J os aS SHAPE TO BE MILLED 243 A card bearing a greatly enlarged profile is used for setting the work accurately be milled by means of a screw and a washer. necessary to leave the rod longer for this purpose and cut it off after the milling is done, but in a good many cases an existing center may be used as a seat for the screw. In some instances it may be The assembly is placed in the miller vise as illustrated, the work being blocked up until the disk misses the table. The first surface it is desired to mill is lined up parallel with the table by means of one or more size blocks or parallels. Then the cut is made and the work lined up in the next position. By repeating the process, completely finishing each cut before the next is taken, the parallels and angles are reproduced faithfully on the work within very close limits. If the drawing is ten to one in scale and is lined up each time to within only }% in., the corresponding surfaces on the work will be within less than .002 in. of their true angular position. In order to hold the various dimensions within close limits, the use of a dial test The indicator is indicator is advisable. clamped to some (Continued on page 121) Power Without Powde, Crosman Pneumatic .) Get aCrosman .22 forX, and Teach the Family" How to Shoot All the advantages of a firearm wi of the nuisance. with none Home Target Shooting Set 4 range in attic, cellar or yarg bullet after bullet through same hole. P Put is air under tremendous pressure—game feet that stops railroad trains. No smoke, we noise to disturb anyone, no shells dro no floor and—NO BOTHERSOME CLEANIRS Keen sport at five shots for a cent (saving op 4000 rounds pays for the gun). A rifie on, surpassed accuracy. Adjustable power for hunting small.game. An Ideal Rifle Stock of American Walnut. Blued: barrel. Deeply rifled with scientific recat Silver front sight and rear peep. Ree weighs 5% lbs. Perfect balance and easy trigger pull. Spool shaped bullet, truest known, aids accurate shooting. Get Xmas Crosman Now Remarkable gift for the whole f; Ask your dealer. If he cannot g you send $15 ($17.50 west of Rockies): ammunition $2.25 per 1000 (west of Rockies, $2.40); lined gun case, $2.95. target holder with bell attachment $2.00; paper targets 50¢ per 100. all — Or write us for interesting ooklet and learn to be a crack shot, CROSMAN ARMS CO., Ine.’ 476 ST. PAUL STREET ROCHESTER, N. Y. ‘70 West King St., Toronto Dealers: Write for proposition in) . Se Magneto “ree Equipped ~ Fag Saws Wood Fast (Does the Work of 10 Men—4 / 20 Cost) This one-profit WITTE Log Saw uses Kerosene Distillate or Gasoline and will eat from 10 te 28 conta at wood a day. Easy to operate and move. New device makes easy startingin any temperature. Trouble- Completely equipped with WI Magneto, speed wer regulator, throttling governor and Z fy wheels, ells trees and sawsthem into blocks —runs other farm machinery. Fast money makerand biglaborsaver. Sold direct from factory to you on your own terms No Intercst Charges. Write to-day for New Free Book and Free=*.;; Easy Payment Prices. No obligation, a ask about Engines, 3-in-1 Saw Rigs or p Outfits, : WITTE ENGINE WORKS 1222 Witte Bidg., Kansas ie Mo. Empire Pi Pa. 7a22 Wiste Siac” * gen Prancions, ae Quick shipments also made from nearest of 25 warehouses. lifier ot affected by a former amplifiers increase in tone quality. Electric Controlling Apparatus ; . 293 Greenfield Avenue Milwaukee, Wis. © _This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. ON Sr in suc of tin in Fi meth anne: unde This Tt Ss 6é ee ae ee ees Oo eek

Page 119

_#8sossgaz ZER2R ' RERRe SES” *. Pa. & SFErsR-o ee hee i Sear ere § ee - Shop Methods: Kinks That Have Helped Me in Tapping Jobs OMETIMES a hole, tapped with a * worn tap, is too small. A trick useful in such an emergency 1s to slip a cut piece of tin over one land of the tap B as shown in Fig. 1 and ‘re-tap the hole. Another method of making a tap cut larger is to anneal the tap and swedge or upset it just under the teeth with the tool E, Fig 2. This method sometimes is used to give a TOOL-E OPPOSITE LANDS ARE GROUND. OFF mananaaaaanannananaen OF TAP A POINT inurl Emergency measures for making a worn tap cut large; an improvised left-hand tap tap clearance. The tap should be re-hard- ened and tempered. In Fig. 3 is shown a treatment that makes possible the tapping of a left-hand thread with a right-hand tap. Two of the lands are ground flat, as at H; the other two are ground very thin, especially the entering teeth, as at Z. By careful manip- ulation the tap will cut an acceptable left-hand thread when there is no time to make a proper tap.— CHARLES KUGLER. “Pantograph’’ Card for Milling (Continued from page 120) projection on the machine bed where it can be made to register both the vertical and transverse movements of the table. As an aid in this work, the differences representing the required number of thousands of each cut from the periphery of the work to the finished surface are marked on the pantograph drawing as shown. If this is done, the work can be milled rapidly to within close limits both as to angles and dimensions. One necessary condition is, of course, that there be enough of a true surface on the work to take hold of it again evenly each time it is reset, although it is not necessary that it always be a rod, as in the illustration. Work of a general square, hexagon or other polygonal cross section can be handled, provided only it be long enough. This is accomplished by casting a babbitt sleeve around the portion to be held in the vise, and turning it on centers, if the work cannot otherwise be safely clamped. Such a case is where angles on the milled part must be at odd angles to the surfaces of the piece. _ Work varying in length from a few inches to several feet can be handled in this manner. For very long work an additional support should be clamped to the miller table near the disk. POPULAR SCIENCE MONTHLY Wi I); hy Dh a My i hee j Ce iy) 9-tube power smashes the barrier of distance Remote stations come in with remarkable clarity and volume even when local stations are on. EW commercial sets made have such power—or power so easily and simply controlled. All the RADIO experience of 14 years is back of this new Priess, the best set that our radio engineers have ever made and wonderful value for your money. Do not buy any radio until you have heard the new Priess—IN YOUR HOME —a Priess dealer will demonstrate gladly. No obligation to buy. Write for names of nearest dealers. Illustrated leaflet on re- quest. e TRADE MARK STRAIGHT NINE “*Outstanding radio performance and value on the market today—without exception” PRIESS RADIO CORPORATION 689 Broadway New York ConsoLe—$335 The one set for cities and other congested areas LOOP OPERATED Single dial control. Wonderful selectivity. Nine Tubes. Tremendous distance. No interference. No background noises. No lightning hazards. In the console there is ample room for all bat- tery equipment. Taste Monet, $195 Setnmiemsenaneoae KALQLEX, good, vest-pocket ADDER, —, X, $6 with book and tables, new methods. (Also, 1-oz. fountain pen typewriter, $10.) BOOKLETS, on request—free. DR. H. E. WETHERILL’S SPECIALS, AUDUBON, PA., U.S.A. 1927 CATALOG JUST OUT! - SEND FOR YOUR COPY -RANDOLPH RADIO CORP. TEST YOUR BATTERY WITH AN SOSo. HYDROMETER without withdrawing the Hydrometer. Balls make reading simple and easy. Swim all three, charged fully Sinks the white, charge still right Sinks the green, charge is lean Sinks the red, charge is dead. Accurate—durable—no float to read or break. Over five million patented Chaslyn Balls used by leading Battery Manu- facturers as standard equipment in — Batteries an Power Tnits. Ask your dealer. If he can’t supply send seventy-five cents to THE-CHASLYN COMPANY 685 4613 Ravenswood Ave. Chicago 180 N. UNION AV... Dépt. 3°-CHICAGO, ILL. © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. } t | : ; | ’ ' j :

Page 120

a mount Show them what you can do Wouldn’t it be fun to astonish your friends some evening real soon by playing the latest popular tunes on your new True Tone Saxophone Popularity; good times; the smiles of those whose smiles you most desire; these will be yours. And you can learn so easily. You Can Teach Yourself If you can whistle a tune, if you can beat time, you can learn to play the Buescher Saxophone, Easily! You can teach yourself, at home, in a few evenings. Three simple lessons given on request with each new Saxophone start you. You learn scales in an hour and start playing tunes in a week. Your progress will astonish and delight you and surprise your friends. Try Before Buying. Easy Terms Take home with you any Buescher instru- ment, Trombone, Cornet, Trumpet, Saxo- phone for six days’ trial. Test it. See what youc an do with it. If you like it, pay a little each month. Satisfaction guaranteed. Send for beautiful free catalog of any instrument and details of trial and payment plans. No obligation. Do this today. BUESCHER BAND INSTRUMENT Co, Everything in Band and Orchestra Instr t 1732 Buescher Block Elkhart, Indiana The Story of the SAXOPHONE Gives complete history and ee idipauie dhe Busses ts se : goran go Bay. nang rst rt. BOOK shams aahete mely te a Clip the Coupon NOW! | BUESCHER BAND. NSTRUMENTCO, amp | UESCHER BAND INSTRUMENT CO. | 1732 Buescher Block, Elkhart, Indiana. { Gentlemen : by Sema oe ag me in any way please e your free litera’ interes: i in- | strument checked below. satins — sf | | Sexophone() Cornet() Trumpet(] Trombone() Tubat) |

Mention any other....cccccccegesccocccccscocccccces | | EE ctnibbi ence Handsome pm Mt: al fd. Tow tel. on been watch hava rines 3miles off const," —Philip Brush. “] across the Mississippj tale People fish’ ay 7 n. “‘I am nearly Years ee “1 I — not another wou no £ ”. AYR. Walker. "1 ees poppet the church clock 6 miles eee Edward Foster. “‘Could tell color of aeroplane 4 miles away.”—Mrs, [, y Yarbrough. “‘I saw ‘a Li ht House 7 miles away.’’—Clyde Scribner

mi Send name and address and Ferry W H 3-ft. Telescopewith free Carrying Casey} come by return mail. Pay postman speci bargain ee of $1.85 plus few Cents post. age. atisfaction foarantecd or money back. Supply limited, order olayt Ferry &Co.,Dept, 1789, Chicagy Tom Sawy_ER} COMING BACK Yes, rightinto your own home, in the Pathfinder. Tom is alive again with all his impishness, his hair-raising experiences, hises. capades, his thrilling rescues, his questfor adventure—the very Same Tom Sawyer who made Mark Twain famous—ayi he’s coming to you in the Pathfinder. The Pathfinder editor is spending a lot of money so that everybody may have achancety tead this most popular of all American stories. The only waytose. cure this story.exceptin costly book formis to read the Pathfinder, Every week the Pathfin der is 1 oaded down with justthe thingsyou wantto read—world news and pictures, brilliant editorials, stories, travel articles, puzzles. humor and miscellany. The Pathfinderis the nation’s most helpful and entertaining weekly magazinewith nearly five million readers —and it comes to you direct from the seat of government. Not sold on newsstands or streets. Mark Twain’s master- piece, Tom Sawyer, will begin in the Path- finder early in 1927. Why not use a Pathe finder subscription, including Tom Sawyer, for Xmas gifts? You can get the Pathfinder every week for one year, $2 issues, for only $2. 3 subscriptions, $2. Giftan- — nouncement cards, giving your name as 4 donor, mailed if desired. If you do not know the Pathfinder and wish to see it, we “3 ‘% will send it on trial for 3 months, Huck Shows Tom 13 issues for 15c, coin or stamps. the Dead PATHFINDER. 336 Langdon Sta., Washingtep, D.G

American ra

BIG NEW 1927 CATALOG-FREE Dealer ents, Set Builders — get our Denia? ’Catsiog 7 225 nationally advertised lines. Lowest prices in America! Largest, most complete stock. Radio’s latest develop- ments. It’s FREE—send fd — om = AN AUTO & le e a Genes Street, Kansas City, Mo.

Tires hammered full of nails,leak no alr, Amazing new invention banishes puncture trouble forever. Punctureshealinstantly while driving. Stopsslow leaks. Prese: r.Ine rrect, rvesru creases tire life, Clean—scientifically co Agents—up to$85 a week |Vaay > —t d proms. No talks 7 35¢ ing—just drive nails in an old tire. Schulte cleared $19.00 in an hour— Willcox,$60.00 first (omen day. Get the facts. Territory goin fast. Full (RSA particulars and FREE sample offer by re- }ETPas turn mail. ACT NOW. a C.F.JOHNSON & CO.,'9 W. Jackson Bivd,,Dept.414 hicago

Read Interesting article on Page 4. ‘‘How $100 a Month, Invested Properly, Can Make You Independent.”’

Page 121

va re CeE AOE eo EE e bs = g 2 PR Asi oo am aie Se HEL ° PS im) —A}f

ur ed st, p= We NC. flo.

ie “SO 3s |

December; 1926

Mer Sop Methods] Tin Sketch Board for Rough Use in Shop

The drawing paper is fastened with wire paper clips to a scrap sheet of heavy tin MOST practical sketch board for rough shop use is a piece of smooth, bright, heavy tin. ‘The paper is held firmly in place with four common wire paper clips. The tin and clips are easy to obtain. The expense is trifling compared to the finishing of a wooden board. The writer has done shop sketching and drawing for a number of years, and is willing to match this “board” with any- thing for simplicity, durability, and prac- ticality —Frank BENTLEY.

Beveled Washer Is Help in Grinding Collars Parallel RINDING milling machine collars accurately parallel often is not the easy task it seems. To handle this work efficiently the writer devised a method that is giving exceptionally good results. One face of the collar is ground at the same setting with the hole. <A bevel is ground on the opposite side of the collar to take a washer made as shown in the accom- panying illustra- tion. The collar is clamped with its finished side against an accu- rately ground plate by means of a rod through the spindle. The second face of the collar then is ground with a cup or saucer wheel.— O.S. MarsHAtt. ACCURATELY GROUND PLATE %\

Collar in position for grinding second face

Dust Groove Protects Threads on Spindle of Lathe IRT, chips and dust will collect in the internal threads of faceplates and chucks so that when they are screwed on the spinde nose, some wear and cutting occurs. To prevent this, a groove may be fled into the Spindle as shown.—F.N.C. THIS SIDE OF GROOVE 1S SQUARE AND

Dust and chips are collected in the groove

POPULAR SCIENCE MONTHLY eA nnouncing 123 the new Srest-O Lite Trikl-Automatic Radio “A” Power Unit | An “A” power unit combining Prest-O-Lite’s fine storage battery with a trickle charger. A unit that can be plugged into an electric light socket, then hooked up to the radio set—and forgotten! It charges itself: automatically. It’s new. Entirely automatic in action. No switches to operate by hand. Now you can have full storage-battery power for your radio all the time. Power that is noiseless and without the slightest pulsation, the kind of power that brings in the distant stations loud and clear. Never again will you have to bother with a charger. Never again will a run-down “A” battery spoil your radio. The unit is beautifully finished in deep maroon. Small and compact. You'll find further details below. But the main thing is to see it. Go to the Prest-O-Lite dealer’s store. There’s one near you. Or write us and we will give you a lot of interesting facts about this wonderful new “A” power unit. And remember, it is made by a company which has had more than twenty years of manufacturing experience. THE PREST-O-LITE CO., Inc., INDIANAPouIs, INnp. New York San Francisco In Canada: Prest-O-Lite Company of Canada, Ltd., Toronto, Ontario LOOK AT THESE NEW FEATURES The battery. Ample capacity. Extra thick, rugged plates, deep-grooved separators, Unusually large acid volume requires infrequent watering. One-piece, leak-proof rubber

case, with acid-tight cover. Screw post seal and double baffle vent to prevent leakage and acid spray. The charger. Built on an entirely new principle. Silent in operation. Adjustable to needs of individual user. Economical to operate. Nothing to get out of order. Nothing to replace. Built to last for years. No moving parts. No bulbs. No electrolyte. No water or acid to be added. No electrodes to wear out. Entirely automatic. No switches to operate by hand. Built-in power relay automatically shuts off the charger when radio is in use and turns it on again when radio is idle. Will operate at any distance from set. Fully enclosed. Entire unit enclosed in beautiful metal case, with hinged cover and handle. Radio dealers should write at once for full details

hoot The Best Gun The NEw BENJAMIN is the finest air rifle ever made. Unlike all others. _Has amazing accuracy -- shoots hard and far, It’s the original American genuine AIR op- erated rifle. One to six pump strokes compress air to any desired degree of power. Same force asin air drills and air hammers except you control the shooting force. Never loses force--no eorings or levers to get out of order. Makes crack shots quickly, inexpensively. Gives years of delight- ———— °5 at your dealer’s, or The sent postpaid. Write! NEW BENJAMIN RIFLE safety and common sense instruction = ents all like. Yours FREE! SEND Now:

America’s Original Air Rifle Outshoots All Others BENJAMIN Get Surprising Offer! Air Rifle & Mfg. Co.,629 N. Broadway, St. Louis, Mo. rIS} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

dies metal, w: other materials. | $ Surnins . «facing, boring, drilling, winding, thread cutting. e le s a bargain at several times the price. re aranteed a high degree of accuracy, quality of materials, workmanship and finish. "The sliderest has travel entire length of bed, Lead- screw inside bed. Hollow spindle. Nc 1 Lathe, plain headstock- - $28.00 No. 2Lathe, back-geared - - - 58.00 Either lathe with 18in. length between cen- ters, $7.00 extra. Complete line of accesso- ries. By all means write for this free book. THE GEROLD COMPANY Dept. PS-16, 120 Liberty St., New York

Page 122

Eviden tly thousands awaited this final achievement The. Silent NOKOL ITH lightning swiftness the new Silent NOKOL has won America! Thou- sands, it seems, eagerly and expectantly awaited this great discovery —Silence— the final touch of perfection. And when it came—a tremendous volume of public en- thusiasm and appreciation came with it. So overwhelming has been this response that in the first 60 days following its introduction home owners, large and small, invested $3,127,461 in this new NOKOL—a phe- nomenal sales record. Consider, for a moment, what the new Silent NOKOL would mean in your home. The first chilly hour this autumn you would set your thermostat for the desired temperature. Then forget it! From that time on—in crisp weather, zero nights or damp days—you would have the right warmth for comfort and health, automatically. You would not need to touch or bother with the furnace. Moreover, there would be no dust, no dirt, no ashes. And remember this: For periods up to nine years NOKOL has proved to be the lowest- cost full automatic oil heat known. In fact, it costs no more than hard coal, usually less. You will want to learn more about the new Silent NOKOL and our convenient budget plan. Mail the coupon today for full particu- lars—and our valuable new guide on oil heat for homes, NEW Silent Neo f CO © -U.S.PAT.O AUTOMATIC OIL HEATING FOR HOMES FREE—NEW BOOK AMERICAN NOKOL COMPANY Dept. 23, 215 North Michigan Ave., Chicago Please send your new book on OIL HEAT. ESSE REE Ee 1 i eee one nee POPULAR SCIENCE MONTHLY How 't to Fit Machine Kiyo (Continued from page 72) After the key has been fitted perfectly, smear a little oil on its faces before driving it home; you'll be thankful if you yourself happen to be the one to remove it later on. Woodruff keys are much used by machine-tool builders and automobile manufacturers. They should fit reason- ably tight on their sides with a minimum of clearance top and bottom. The key- ways for this type of key are milled with special cutters for each size of key. The standard depth of the cut is gaged by the diameter of the shank; in other words, the cutter is sunk in until ‘the shank just touches the shaft. HESE keys are usually made of cold rolled steel and require very little fit- ting. They are sometimes sweated into their seats to makea very solid job. This is done by tinning the key, heating the shaft slightly in the region of the key seat, and placing the key in its seat. To tin the key it must be polished all over. Dip it first in the acid, then in melted solder, and allow it to cool. The shaft may be heated with a blowtorch or any other convenient means, pref- erably in a gas or oil furnace as a coal fire is apt to leave a deposit in the keyway. When fitting any kind of a key it is important to keep the corners well rounded and the ends beveled, and be certain that the bearing is on the flat surfaces and not on the corners. The beveled ends prevent the key from up- setting while it is being driven and also make it easier to remove. If a key bears the least bit on any of its corners it may cause a false bearing, in which event it will loosen up quickly in service. In driving a key home it is best to use a “set”’ or block between the key and the hammer. Direct blows from a heavy hammer may cause the key to swell and stick hard in its seat so that removal will be extremely difficult. EYS are often stubborn things to ex- tract and it is sometimes necessary to resort to heating or drilling. A badly stuck key may be dealt’ with by heat and hammering and the liberal use of kero- sene. A good hot torch flame played over the outer surface of the keyway often will help. Kerosene should be squirted into any small crevice with an oiler to dissolve the rust. Peening with a ball peen hammer directly over the key- seat also will help to start an obstinate key. Key drivers can be made out of good chisel steel, drawing the body out into a long, rectangular-shaped punch and tempering it about the same as a cold chisel. The tools should fit loosely in the keyways and be ground off perfectly square on their fore ends. Small sizes can be made out of drill rods. Pinch bars and wrecking bars, wedges and taper chisels also are useful in removing keys that resist ordinary efforts to remove them. When a gib (Continued on page 125) © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Keeps out drafts, rain, snow, suct Solid Comfort at very Slight Cost Wirfs Home Comfort Weatherstrip costs only & per foot. (Slightly higher west of Rocky Mts,) Dealer cuts it off, like rope, froma reel. No waste, You apply it ourself, easily. A tack hammer only tool needed. Weatherproof, dust-proof, vermin-proof, lasts for years. More than 300,000 doors and windows were made weather-tite last year with a RFS IMFORT WEAT H ERS TRIP Is effective, even if doors and windows are sagged or warped. Insist upon*‘Home Comfort.” The name and foot-mark on tacking lap are little things to look for but big things to find —they identify the genuine. Your dealer hasit orcangetit. E. J. WIRFS ORGANIZATION Sole Manufacturer and Patentee 114 South 17th St., St. Louis, Mo. SVADDING MACHINES im New Pocket Size, does work of $300 Guaranteed 5 yrs. Made of Steel, nota ry TRIAL SEND NO MONE ust gay and =. le will moi imped a ately ‘ay pos n plus postage on deliv- eeoUlrions. 4 imi ery. If not satisfied after 10 day ti MULTIPLICATION | refunded. Agents wanted. DIVISION BAS8SY CALCULATOR SALES CO. P. O. Box 1118, Chicago, lii., Dept. 13 trial money ZIP- ZIP / Here is a letter we received from a lady from way out west. Gentlemen: My boys were so delighted with the = 9 zip shooters that they ordered from ou that | an enclosing check for one » | want each of their srtons to have one also. Please soma these as soon as possible. Thousands of boys are py with this wonderful Zi ip-Zip shoot- i er. Order from us or \ your dealer. 35c each or 3 as $1.00. Send stampa, re oin or money order. AUTOMATIC RUBBER CO., Dept. 22, COLUMBIA, S. C-

Page 123

ly 8c mer

How toF (Continued from page 124) +. ysed on the end of a shaft, as in the ok gO a flywheel, the projecting head should be covered with a hub cap to pre- yent accidents. In prying out such a key, it is well to support it on the under side with a jack or block of wood. That prevents the key from bending under the strain of the lever. The last resort, if a key resists all other ways of removal, is to drill and tap a hole in the end for a bolt or stud. The polt will serve as a jack in conjunction with a strap and block placed against the shaft or hub. By tightening the nut and hammering lightly against the bolt at the same time, the key ordinarily will re- d. i hole may be drilled the whole length of the key, if necessary. This weakens its hold. By tapping part way in for a bolt or stud, the key generally can be removed;

PRY BAR | \Ws

FEATHER KEY

HEADLESS SET SCREW LL %Y =n MSSESSSSS REMOVING GIB HEAD KEY THREADED KEY

i Gilli: ws SS ( SHAFT HUB STRAIGHT KEY Removing a gib key; straight and feather keys; a threaded key for experimental work

os penne italso can be crushed sideways toward the center with a cape chisel. A pull on the bolt or stud is then generally sufficient to withdraw it. Often when repairing or overhauling machinery away from the home shop, keys will stick in spite of all one can do. A square key sometimes can be removed, if a driver is not available, by using a pair of nail pincers, the sharp jaws of which are closed into nicks made in the side of the key with a sharp cold chisel. A key sometimes used in light ex- perimental work is the threaded screw pictured in the illustration above. This not only acts as a key but also holds the gear or pulley in a registered position on the shaft. After the machine has been taken apart for repairs or to make changes, a gear so keyed always can be restored to exactly the same lateral position, as the threads must line up be- fore the key can be inserted. Fitting keys brings to mind the actual case of Tony, a new machinist in my old shop. Machinists were scarce at the time, and although Old Bill, the fore- man, had his (Continued on page 126)

Use Tees Parts 4—Victoreen 170 R. F. Transformers, each. $7.00 1—Victoreen 150 Coupling Unit; eaeh...... 4.0... $5.50 1—Victoreen 160 Antenna Coupler, each..... $3.50

Victoreen Master Control Unit A completely assembled, convenient, single control unit for use on circuits employing two or more condensers of the same capacity. POPULAR SCIENCE MONTHLY

Dependable Standardized Parts with a World Wide Reputation The fact that Victoreen Super parts are used in many thousand sets all over the world is proof of their merit. Victoreen Super sets are free from oscillation, howls or squeals. Their “B” Battery consumption is exceptionally low—less than some three tube sets. Victoreen R. F. Transformers are made with air core con- struction. They are not merely “matched” but are actually tuned to a guaranteed precision within % of 1%.

Victoreen Rheostats

Zero temperature coefficient. Double the num- ber of turns of wiring used on ordinary rheo- stats. Three terminals simplify wiring. Five resistances, 2, 6, 10, 20 ohms, each. .$1.20 Potentiometers, 200 and 400 ohms, each. 1.50

Victoreen Master Control Unit. SEMA She cca Baie ui sisioatet othe cteien $19.50

Extra condenser, €achi..)s. en or_ pencil. omplete Outfit §3'so Prepaid Anywhere. Interest- ing illustrated circular free. Write to- y. Agents wanted. ARKOGRAF PEN CO. 1171-A East Stark St., Portland, Oregon io at startlingly low prices. Get lete factory-built set 3 also please send

Chicago, U. S.

Increased Selectivity Carb Greater Distance More Volume BUT ABOVE ALL— Quality of Tone On any set from the modest little Crystal Hook-up to the Super Outfit—you simply install - THE CARBORUNDUM STABILIZING =“ DETECTOR UNIT pee

/ $3.50 (in U.S.A.) Dealer or Direct © / Carborundum ’ P’. Company Our Hook-up Book tells you how—send for it / Niagara Falls, N.Y. : a nd f / lease se ree THE CARBORUNDUM COMPANY, NiaGara FALLs, N.Y. 3 Hook-up Book D-6 SALES OFFICES AND WAREHOUSES IN a New York, Chicago, Boston, Philadelphia, Cleveland, Detroit, / Name___ ——— Cincinnati, Pittsburgh, Milwaukee, Grand Rapids o Street 4 WCE Y___ ——— —EEE The Carborundum Company, Ltd., Manchester, Eng.

con Carbide. This ‘rade Mark is the exclusive property of The Carborundum Company. Po State 7 is the Regi d Trade Name used by The Carborundum Company for Sili- ra

/

© This seal on a radio, too! or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 124

POPULAR SCIENCE MONTHLY Pressure-Gauge for ‘‘Steamy’’ Production How hard is your machine being pushed for higher production? — a Counter will tell. How effectively is develop- ment-work being pushed on a new machine? A Counter will tell. If you want more pressure behind production or more ‘‘push’”’ behind de- velopments, fix it so the extra effort must register The Set-Back Rotary Ratchet Counter bélow is for machines such as presses and metal-stamping machines where a reciprocating movement indicates an operation. Registers one for each throw of the lever and sets back to zero from any figure by turning knob once round. Supplied with from four to ten figure-wheels, as required. Price with four figures, as illustrated, $11.50 subject to discount. (Cut less than ¥ size.) Set Back Revolution Counter of similar model, $10.00 (list). The “Form UM” Magnetic Counter below counts operations or units of output, from any distance that wires connect with machines. Can be placed over desk or on convenient Counter- Mechanical contacts on your ma- chine make and break the electrical cir- cuit which operates the counter. The electro-magnetic drive can get its cur- rent from your regular lighting circuit (110 volts), or from storage battery. Write us about that counting problem of yours—or write for the counter catalogue. The Veeder Mfg. Co. 44 Sargeant-St., Hartford, Conn. Shop Methods. How to Fit Machine Keys (Continued from page 125) doubts as to Tony’s ability, he never- theless gave him a chance to make good and put him to work fitting keys on a big machinery job. Tony worked half a day unobserved, but after the lunch hour Old Bill gave him the once over from behind a big casting. The key upon which Tony was then working had been made undersize and the gear did not tighten up when slipped on to the key. Slyly taking his pocket- knife, he cut several paper shims from a newspaper to place under the loose key. Old Bill then descended upon him and headed him abruptly for the paymaster’s window. “PPSHINK about six inches ahead of your work,” was the advice given us young fellows one day years ago by Old Bill. He, strange to say, really practiced what he preached. Here is how he ap- se it to his work when fitting machine eys: He cut off a piece of stock to make a key a few inches longer than necessary. A cut or two over one side in the shaper brought the key to the approximate size, with the necessary taper of \% in. to a foot. Slipping it into the keyway until it bottomed, Old Bill had his cue mark for cutting off the projecting ends. And while other mechanics were taking fine cuts and filing their heads off to make a fit and trying their best not to get their keys undersize, Bill just loafed along, never appearing to hurry, and yet beat them every time. Compare his method, which involved only the loss of a few ounces of steel, with the time consuming fit-and-try efforts of less skilful ma- chinists. “Lock your power grip with a key well fitted and be proud of your job,” is a motto often quoted by Old Bill, who knows how to fit keys properly. If you are a regular reader of this de- partment, you are familiar with the exploits of the machine shop foreman known as “Old Bill.” Joe V. Romig, who wrote this article on keys, was one of many fine machinists who learned their trade under Old Bill’s kindly guidance. The article, it might be added, has just come to light among some old papers; it was written by Mr. Romig in 1922 shortly before his death and represents his last work for PopuLar Science Montuty. Block for Bending Tubing ARAGE men and others who have to bend brass or copper tubing will find the block shown an aid in turning out | good-looking work. 7p Theholeisabout 4% / in. larger than the / tube. The blockcan ii be held in a vise, or by hand.—H. L. W. HARDWOOD Makes neat bends © This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. December, iy, MASTERPIECES (FRESHMAN Y | MASTERPIEcr A Perfectly designed ra- dio. Massive - beautiful; just what you want for your home. No matter how exquisite your furnishings are this genuine mahogany upright Console will lend additional beauty. Sold on easy terms by FRESHMAN Dealers Model 6-F-11 Wette for new booklet, Mostrating and decerthing the ontinal line eceivers 42! 0 We: ay 8. of Breshman MCHAS. FRESHMAN CO., Inc. sat reshman Bidg., New York 2626 W. Washington Bivd., Chicago 2S RI AN EASILY MADE SMOKING CABINET VERY man who works with tools— whether he is a novice or a “handy- man” with long experience—will find it easy to build this handsome smoking cabinet. j Space for cigars, cigarettes, match boxes, cigar and cigarette holders and pipe cleaners are provided. A feature that every smoker—and his wife—will appreciate is the ash trays (which are removable) at both ends of the cabinet. When not in use these ash receptacles can be closed. _ : . Blueprint, including full details for making this handsome smoking cabinet, can be secured by sending 25c to— Popular Science Monthly 250 Fourth Ave. oe New York wf lial!) seeaa 22 BW sre BEASHSTOLSPES SP yess? me —_ aa sore cou MD Be

Page 125

POPULAR SCIENCE MONTHLY

ke Your Watches, Clocks, Etc. Visible by Night 2:, very latest discovery in the scientific world. Hitherto, tically ly paobtainane sean pt at an exorbitant rice, we have at last sata Pais ia tee of white I LUMINOUS P. which, s risctly visible to , THE MORE BRI tee ae ne te rendering it an do i ittle will enable 9 oa to to tell the time by night. na ot, ots plates o your electr moat tie setts la ete email a ‘articl persone Transmitter Button

tcios Pelee we. * You can easily make a highly sensitive detectophone by using this Transmitter Button to collect the sound waves. You can build your own outfit without buying expensive equipment. It is simple and inexpensive. ou can install an outfit in your home and hear conversations being he! over thi ouse. u can connect up different rooms of a Ahotel. This outfit was used by secret service operatives dure Ba ing the war. It is being used on the etaze. It is ultra-sensi- tive and is the greatest invention in micro-phones, You can mount the button almost anywhere—card board boxes, stove ipes, stiff calendars, on the wall behind a ponte frame, etc. utton is so lisht and small it cannot be detected. Persons can be overheard without suspecting it. oor can listen in on conversations in aang room, A deaf person in the audience can hear the Connected to paonosrsph, De piano or other musical aerummeds music can heard hundreds of feet away. Button may be used to a. telephone trans- mitters; often makes an old line “talk-w when nothing else will, The ideal microphone for radio" Bee: carries heavy ly sensitive. auapiifaes radio signals. Countless other similar Experimenters find the Button veeful fod hundreds of hones, amplifiers, loud speaker: Many fasci- as neliins ee button acaings “the throat or chest 8 in a aus reproduction of istol; actuall Real BLANK CARTRIDG miniaturesize. Ilus- 1% inches long, with ring at end for attach- ing to watch chain. ads like a regular Pistol is break-open syperis Made Regeneedl of nial grade steel, nickel plat n box with cleaning rod. pearl handles.” $2.50. “INVISIBLE INK iiaatis ed, octa- PRI BLANK CARTRIDGES, 50c d it ff with a loud ba Get So tiene oo fo loading. "M inde on et somely bis. Be Syahid with NEW Ww BOOK ON ROPE SPLICING ractical i

ot be know the eret, tovalgabie for Fay ee private ais and other p to y from G sat fan for pl jokes. Only 2! oO eyes.

ae ers, campers, Bottle men. Price be ET. T Bi BLE IDCE “ REAT CURIOSITY A gen- K...3 be seen to. be a ke gi money selling them t to og pte acquaintances, : sf Pp E 1Sc each, 3 for 40c, 12 i $1.35, 100 for $7. .50. Also Sbtainable in Leather Binding, with gold —_. Price 50c each, 3 for $1.25, .50 per doz. Magnifying Glass for use with Midget Bible, 15c. Every Boy His Own Toy Maker) Surprise Matches Greatest boys’ book} written. Tells how tolyieng jum than make a Pinhole Cam- era, a@ Canoe, model Railroad, a Telephone, Boomerang, Telegraph my Pe Box — alking Machin Microscope, Plectric Motor, Blectrié Door Bell, Water Wheel; Paddle onie, a Dog Sled 150° illust Baie ane, ete. 64 Price 10c per box, 3 boxes for o , so i $3 for2se, E,/25¢ postpaid, 12 for 75 cents. MAGICIAN’S OUTFIT Bpperatus and Directions for a Number ysterious Tricks Enough for an tire Evening’s Entertainment Be ANYONE CAN DO THEM mt | 5¢ a’ - Tt is great fun mystify ing penis f riends. Get jure ill be t! e regular Safety Matches. As the victim tries to light one he gets quite a surprise.

en Ball is placed enti and upon re- the lid has d and is found someone else’s pocket); ‘Lhe Magic nee with ee you can apparently cut your finge alm wo; the Wonderful Card ‘irick oe card 3 is placed in an envelope, a open an nventirely different card altogether is found); The we gaara mand wien a is n the little wooden barrel, and, when opened ag: is found to have vanis! matesty, or can be. made to change into a coin of heer ay denomination); The Famous Dissolving Penny ‘Irick; The Glass Goblet and ae Coin Trick (a eoin is drop) into @ glass of water, and when the water is out the coin has vanished), With the tricks described above we send full’ rinted din instructions for performing each trick, so that anyone can readily perform all the tricks to the great amusement of their friends or the public. Any boy of ordinary intelligence, with this t of Tricks in his possession, can give a parlor entertainment not inferior to some regular magicians. Besides the tricks contained in the Cabinet, there are many other feats and illusions fully explained — — printed instructions, for which you make or procure the necessary apparatus. This unexcelled Cabinet of Tricka for ONLY 75 CENTS POSTPAID TO. ANY ADDRESS. A DeLuxe Edition of our new 1927 CATA- LOG mailed on receipt of 25c. Only book of ite kind im existence. 550 pages of all the tricks in magic, the newest. novelties, ag gam es, sporting goods, interesting curiosities in sods and plants, etc., unprocurable elsewhere.

Withabunen of these bills, itis easy for fills oF . pr one and Peeling off a genuine PT or two from the outside of the roll, the effect created will be found to be all that can be Gesired. Prices, postpaid: 40 Bills 20c,125 cor 50c, or $3.50 thousand postpa Tube | Wonderful — instrument you can see orio Fee ii LS a > tem, a i 9 similag, luslons, eS Dystery hat ne . Johnson Smith & Co. Good Luck': AVERY striking and Tosommen clas Silver | nish, exull @ — — with tee paint a hing aparkling out of the ores. Said iby jig rag 45 bein Luck to the Ri Very y, unin ng ring the that: oon will take a pride fa Exploding ene

JUST LIKE ORDINARY CIGARETTES. BUT SUCH REAL STARTLERS! The box contains ten genuine cigarettes of excellent quality. Aka. appear go real, but when each eal smoked, thevictim foud "BANG"

great egies as it goes off with a great mirth provoker yet 25c per box. miaiine’ ies Charms ONLY 3 for 40c; $1.35 doz, pretty little curiosities and decidedly Fitted with Magn _ ying _paneee that tge the pictures to a v urprisi ing degree: in fact, it ne aimoet incredib le that a yet Dicture could be possible in such a small com- and | bow sharp and distinct they show up when you look through, pe Es Ma My Locd's Prayer in type. tes CIGARETTE MAKER , QGARETUR KER Very, novel. MAGIC ic FLUTE. Wonderfally Swest Toned and Musical The Magic ae cod nova 1 ie no fingering; and o il kind: ibaa: Wingate or any other musi tos piane A ny wii a Badges

Kissing Permit 1 er T: Two very Goel metal badeen, nickel plated, that you can wear, giving you fun out of all proportion u their trifling cost. 10c, each badge, 3 fo per doz. p.pd. ADDRESS ORDERS FOR ALL GOODS ON THIS PAGE TO JOHNSON SMITH & CO. pert. 350 RACINE, WIS. ve mastered ce 7ou se wih incite iment BLANK CARTRIDGE PISTOL e ttern of the latent the earance which volver, lone 8 enough to scareab lar, w! loaded, it : will probably effective as a revolver with real ~ lets, without the danger to life. It takes. amd stan Bi , that are cptainnts m™ everyw: ere. Even the most timi women can use it wi eataty and frighten e this? with. ou on Sone J Iya out risk to herself or or aapane al sie; it the danger per ata and ng poms. out acteched er revo) bers aro PRICE * ONLY 321,008 Blank lid Metal. 2-ca) spjoned by ox: press only, 50c per ‘160° Johnson Smith & Co. Lee hs: acine, Wis zin Mystic peter Snee g Powder Mi napa Serpent’s. Ess Box contains 12 eggs. lit with a match, 7 ws e hatches id sneezing the time of f your ate ie. For cal rides, or any place at all where there te a gathering of people, it is tho greatest loke 3 out. Price10cor : BOYS !

BOYS! BOYS! THROW YOUR VOICE Into a trunk, under th > bedor anywhere. Lots of Lig fun fooling the teacher, policeman or friends. THE VENTRILO a little instrument, fits in the mouth out of sight, used with above for Bird Calls, etc. Any- one can use it. Never Fails. A 16-page Course on Ventriloquism, and the Ventrillo, ALL FOR 10c postpaid. ITCHING POWDER This is another good practical joke; the intense discomfiture of your victims to everyone but ‘themselves is thoroughly enjoyable. All that is necessary to start the ball rolling is to de- fogs a! little of the powder on a person’s hand ng powder can be relied upon to do the — e result is a vigorous scratch, then some more scratch, and still some more. 40c box, 3 boxes for 25c or 7Se per doz boxes. Great Fire Eater SQUIRT ROSE Most Sensational Trick ofthe Day! With the Fire Eater] +, in his possession any] 25 person can become 4] ‘ perfect salamander, apparently breathing fire and ejecting thousands of Te and consternation of all beholders. Harmless fun for all times, seasons and places. If you wish’ to pro- pe Fs ee ee oe sae sweet that everyone ie ompted to takes ne orhood don’t fail to procure inhale eine materia: in's handsome] Bah her ist his Sere '» the: im: box, the cover of which is highly rubber nape easily “reaches te the ornamented with illustrations in Pee & kane eee eee ze enough to make a d various colors. Price of all com- ICE 250 hi h ls plete only 30 cents, postpaid. | Sch or" 3 for 68e ponnia. A REAL STARTLER. This ‘is the most popular of all eect tricks. The coa

Wonderful ment. Instru- Greatest thing yet.- Nine sep- arate articles in one. verybody , Seliphted with it curious and interesting. Lots of pleasure as well as very useful. It is a double Microscope for examining the wonders of nature. It is also an Opera Glass, a Stereoscope, a Duruing Lope, a Reading Glass, a Se scope, a Compass, a Pocket Mirror, and a Laryneseco —for examining eye, ear, nose and throat. It is worth all the oun to locate even one painful cinder in the eye. Folds flat and fits the Don’t FL it. by Post pocket. Something great—you_need one. mail, postpaid. Price, only 35c¢ or 3 for $1.00 USHES The Wonder of the World Japanese Rose Bushes bloom all the year found. Just think of it. Six weeks after planting the seed, the plants will be in full bloom. It may not seem possible, but we posi- i it to be so. They will bloom every ten » Summer or Winter, and when three years old ‘the bush will be a mass of roses, bearing from five hundred to a thousand roses on each bush. The flowers are in three shades white, pink, andcrimson. The plants will do well both in and out doors. We guarantee at least three bushes to grow from each packet of seed. Price, 10c packet, 3 pkts. for 25¢ postpaid.

Postage Stamps Accepted

© This seal on a radio. tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

127

Page 126

Even if you can’t _ drive a nail straight you Z can iy a peste buil d The finest set you ever heard HE set that radio fandom is talking about—and building, in tremendous quantities,can now be built by anyone. No matter if you have never built even a one-tube set before—no matter if you have never had a screw-driver in your hands before—you, with the book, “How to Make a Daven Bass Note Circuit,’”’ can equal the jobs of an expert. Every conceivable question is answered. Every part is shown life size in the drawings. Every connection is numbered—and with the “A B C” wiring chart no one could possibly make a mistake. The Daven Bass Note Set in its new two dial layout is even better than ever before— the new Daven Balancer and Compensator make tuning even sharper and easier than ever before. Get the book today—it will be one of the best radio investments you ever made. The Daven Bass Note Set will open your eyes— and your ears! Your Bass Note Set will be the talk of your neighborhood,—everyone will want to copy it. Secure your copy now, as the first edition is going rapidly, and you might have to wait for another printing. Bass Note Circuit for Complete Radio Reception © Zh New 8th Edition Daven Manual This valuable book ex- plaining Daven Amplifi- cation. has been just newly revised. It will tell you in full detail how to apply Daven Amplifica- tion toYOURset. 25c at dealers, 30c by mail. “Dhe Sine Af Merit i : =) l AVEN \RAD/I\0/ CORPORATION tance wank “Resistor Specialists” eecisterco 192 SUMMIT ST., NEWARK, N. J. FREE CATALOG ON REQUEST Ra eene Oana E POPULAR SCIENCE MONTHLY Pixstier Shop Methods Repeating Odd Shapes on a Shop Drawing Stam accurate repetition of an odd or irregular shape in a drawing, if re- quired many times, is frequently a diffi- cult and tiresome job. In isometric work, the re-drawing in accurate alignment of the same ellipse representing the section of a shaft or a hole, often among a maze of other lines, is one of those things that take the joy out of life. That is especially true when the work is small. The many construction lines run close together through other permanent and temporary lines and are interspersed with dozens of pinholes made by the compass. All these troubles can be avoided by means of the simple method illustrated. It consists in making a templet from paper-thin cellu- loid and using it stretched over the /{ hole in one of the | regular triangles, Blank camera film | is just right for this | purpose and can usually be had for nothing. A drawing of the required shape is first made some- where on the board, and the piece of film tacked over it. Next, necessary |Z center lines are drawn on the film so that they will be plainly visible finished. The drawing is scored on the film with dividers or knife, depending upon its character. An ellipse such as that shown in the drawing, for instance, is best made with a bow divider, and it is preferable to go over each arc several times instead of trying to score the full depth at one cut. Other shapes can be made with a knife and French curve, and in that case a single cut will be enough. When the scoring is done, it will be found that by bending the film, the core can be broken out clean. The border of celluloid is trimmed to leave about 1% in. margin for overlapping on at least two sides of the hole in the triangle on which it is to be used. It is stuck on with a couple of daubs of library paste. When the job is done, the templet can be pulled off and preserved for future use. After a number of such templets have been made, the draftsman often will find that he can use one of these for some new job he has to do. Screw threads, coil springs, multiple disks or annular grooves and similar work in isometric drawings are a few out of many instances where templets of this kind can be used.—H. S. | N ) A\\, , AX \ 4 px > tl }|30 “ANGLE Drawing ovals with a celluloid templet when the templet is Worn oilstones and razor hones can be lapped straight with emery and water on a flat iron plate. ae December, % Get Rid of Your HAT unsightly, uncom- fortable bulge of fatty tissue over the abdomen is an unnecessary burden. Here’s the way to get rid of it without fasting, hot baths, or back-breaking exercises. The wonderful “Little Corporal”’ belt will With “*Little Comm ral’? Reduce Your Waist 4 to 6 Inches Quickly! This remarkable belt not only te duces your girth at once, but keeps your waistline down, Tt fits as perfectly as a dress glove, No laces! No clasps! No buckles} N Straps! No stiff supports! It's built for comfort. Young Man! If your waistline is beginning to | now is thetimeto stop its growth andy 4 retain your youthful figure. Don't wait } until you havea regular ‘‘bay window” Guarantee Offer! Send coupon today for free deseriptiyg literature. If you prefer, Sive us your waist measure (snug) over underwear enclose $6.50 and get the belt, or pay postman on delivery. If not entirely satisfied, your money will be prom and cheerfully refunded. Price is $6.59 no.matter where you live. Patrons 3 calling in person will receive our ‘seas ee ,, usual prompt attention. Mail coupon Little Corporal Now! "SSS SS SSS SSS SESS SST SSS See, THE LITTLE CORPORAL CO. y,2bo,, Dept. 12-S, 1215 W. Van Buren St., Chicago, Ill, Please send free descriptive literature and Guarax tee Offer. OC a a ee er FE Coa ee ee State. ...... age If you prefer to order a belt, fill in below: fe Pee ee Weight... am ‘CARTER ‘*Midget’’ Rheostat with Filament Switch *R.M.A. Standard As soon as knob is turned from ‘‘off’’ position, filament circuit is closed. One less knob on panel saves space and simplifies set operation. Resistance ele- ment clamped in metal frame. The wire cannot move and short circuit. Smooth, noiseless, compact. Any dealer can supply In Canada: Carter Radio Co., Limited, Toronto Skin Troubles Cleared Up—often in 24 hours. . To prove you can be rid of pimples, blackheads, acne : ¢ eruptions on the face or body, barbers’ iteh, eczema, enlarged pores, oily or shiny skin, simply send me your name and address today—no cost —no obligation. CLEAR-TONE tried and tested in over 100,000 cases—used like toilet water—is simply magi in prompt results. You can repay the favor by tel your friends; if not, the loss is mine. WRITE TODAY, © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. E.S.GIVENS, 458 Chemical Bldg., Kansas City, Mo.

Page 127

- -_7rre

All this time, ee pecember, 1926 [ “Cave-In”

(Continued from page 11) crushed beyond recognition. oe iirough that night, and the next day, the first efforts of those above to ytrate downward through the shaft ee all but hopeless. Death lurked a ay step; for now and again a loos- “ ed boulder fell and roared into the inky blackness. The lowest depth to which the uers could penetrate was the second level, about 200 feet. Between them and the imprisoned men there remained near- jy 600 feet of debris. They knew they no sink a new shaft, rebuilding the shattered walls, a foot at a time, from the top down. And so, while some of the rescuers dug into the debris, others were busy rebuilding the cribbing with planks, posts and steel girders. ee These were the “front line” men. Supporting them from the rear was a force of men and materials concentrated

top of the shaft. Here were stacked . of is of lumber and steel for the bulwarks. Here crews of timbermen cut huge mine timbers to the proper size and shape. Other crews of welders burned steel girders to size and bored bolt holes by which the girders could be fitted in place below. OW and again there emerged daring N heroes who, in the desperation of struggle, gambled their lives in attempts to explore the black hole. Alfred Maki was one. During the first hours of rescue he risked being crushed to death by boulders in a vain effort to climb upward from the bottom of the shaft. On the second day, he was lowered from the top. But his powerful light could not pierce the gloom of the abyss below. Another miner, John Matala, made the attempt. Three minutes:after his return to the surface, a cave-in dropped tons of earth into the shaft where he had been. The second point of attack—that of drilling a narrow communication hole 412 feet deep straight downward from the second level—offered little more hope of immediate success. ‘Three precious days passed before the drilling could be started; for it was necessary first to dig a tunnel twenty-seven feet upward ‘rom the secend level to enable experts to in- stall a diamond drill. ; This drill consisted of a short piece of pipe, in one end of which were set five diamonds, as in a diamond ring. The drill was screwed into a longer length of pipe and revolved by compressed air. Biting through the earth at the rate of about three feet an hour, it had gone down about a quarter of the distance toward the goal at the time of the rescue. ate third onslaught, directed diag- onally upward from the thirteenth level of the neighboring Aurora shaft, seemed to offer the best hope of success. Here a rescue crew of sixteen men, work- ing in four-hour shifts, toiled ceaselessly with their drills to open a narrow way into the dungeon above. When the rescue came they had gone more than halfway. They had dug 280 feet, with about 200 feet still to go. (Continued on page 130)

POPULAR on the first. Cannot Leak Not the tiniest drop of ink will spill although one filling is sufficient to write thousands of words, Makes 3 to 4 Carbon Copies at one time with original copy in ink, Bear down as hardasyoulike, with- out fear of bending, spreading, injure ing or distort. ingits 14Kt | The Perfect Writing Instrument’ GREATEST VALUE EVER OFFERED Answers the purpose of both pen and pencil combined. Its point is shaped like a fine lead pencil point and writes with ink free and easy without a miss, skip or blur. The steady uniform flow of ink actually im- proves your handwriting. Won't blot, scratch, leale or soil hands. Combines The Best Features of pen and pencil, minus the weak points of both, plus ime provements not found in either, The lead pencil smudges, the point breaks and its writing soon is obliterated. Most fountain pens skip, scratch, flood, clog, leak, blot, soil hands and clothing. The old stylographic inle pencil dries up, balks, blots, writes heavy, flows unevenly and is never reliable. The Inkograph feeds as fast and uniform on the 2oth page as it did

185-43 Centre St., New York City SCIENCE MONTHLY

Lines toa Ruler without smearing, smudging or blurring the paper. Writes with any color of ink, Requires No Blotter The ink dries as fast as you write, because the flow is fine, even and uniform. Patent Automatic Feed Prevents clogging. No complicated mech anism to clean or get out of order. A year’s guarantee certificate with full directions accom panies each Inkograph and is your absolute Protection. An Instrument of Refinement In appearance it is extremely attractive. It’s beautifully - highly polished finest quality of hard rubber, its sgKe Solid gold point and feed, gold band on safety screw Cap, gold self filling lever and gold clip makes it an instrument of distinctive elegance and refinement. Made of Black, Red and Mottied Hard Rubber Each Inkograph is designed and finished to please the eye. The equal in size, workmanship and material of any $7,$8 or $9 fountain pen. Also made in ladies’size, SEND NO MONEYs Your name and address are suffiicent. Pay postman $2.98 plus postage on delivery. Black Rub- ber Inkograph illustrated will be sent unless you state you wish a Red or Mottled. Specify if you want ladies’ size. When cash accompan- fes order Inkograph will be sent postage pre- paid. Ifwithin ten days the Inkograph does Not prove satisfactory return it and we'll refund your money. INKOGRAPH CO., Inc.

ite Writing aletbeivalal= That 14kt solid gold ball like point is » round and smooth, glides with ease over the coarsest paper and makes it possi- ble to write in ink as rapidly as with the softest lead pencil. Sell inkographs mak: ger profits, ° Drices, no collecting. no Competitive ‘Send tor ‘an inkoprapht cr wales Sor speed eee Teae has yd

To Every Buyer SEND NO MONEY specia. HIGH mediately.

Complete Gripsit outfit, includ- ing gold-plated blad cially peeeces Newshell a pig grain keratol case, $1.49. GRADE GIL E SAFETY RAZOR and BLADE FREE to those who order im- s “¢ 9 Write, giving us BOO Go* a make of your razor. Pay postman oot? ayo ‘ or 90%. sale price, plus few cents post- Cc SPAS Qe 0% Ome age. You are the judge—money WANTED Tp <0 ge aX nd0? back if not 100 per cent satisfied. ay) 3 OK be at co GRIPSIT CORPORATION, ‘Seeeeton « posiien-= “Butld your own with “RASCO” Parts” DEPT. J-1 full or part time. No Radio Specialty Co., 96-P Park Place, New York, N.Y. 405 Broadway Cambridge, Mass. Write immediately.

Shave With 1 Razor Blade for weeks and save $5 to $10 quick, smooth, perfect shave EVERY DAY, Gripsit, Perfect Strop- per, is a wonderful . new device that en- ws ables you to strop MQ a safety razor blade to hair- & splitting Nehd keenness e holder, spe- LETT

Sells on sight. Every r)

© This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Genuine Diamonds Guaranteed = Cash or Credit ff Give a Diamond for Christmas! Buy from Loftis, the Direct Importer,and be sure of highest goality and most value yy money. Our mi k. Wey Mountings are the latest creations in 18-k white gold, elaborately carv: hee and pierced. Sati: 4 d, or money back. Goods sent for vy, Your free examination on request. Credit Terms: Pay one-tenth down; thy at your i an 2 SSS See p mon’ your convenience. Se) goods delivered on first Christmas Catalog Free! P Big 132-page book, illustrating our Diamonds, W: eiry, Silver ware, and gift artic for ail oceasions, seng absolutely free. Write The Old vp me mlOr TIS: 2 Jewelers BROS.& CC. fF. Chicago, (ama : 852 oo

19-Jewel Adjusted Waltham No. 846—14-k white gold filled; as- covtadpatecene, 043.50 $4.25 down and yt a g qe week —— We carry alt standard 4 Solid 18-k white gold Wedding makes of Ratlroa } Rings. Beautite ly engraved Watches—guaranteed ; d carved a floral patterns ¢0 pass inspection. zs Credit at ] Ne: pg 33:38 Cash Prices RAT PEK SSS Fe ian SRD

Page 128

AMPERITE has been universally adopted by all leading engineersandset- builders; accepted as standard in every popu- lar circuit. Eliminates hand rheostats. Simplifies wiring. FREE—Send for‘‘ The Radiail Book’’, containing the latest popular hook-upsand construc. tion data, to Dept. P. S.-4 AFeadiall Company 50 FRANKLIN ST., NEW YORK Price $1.10 Complete REG. U.S. PAT OFF The “SELF-ADJUSTING” Rheostat PERITE LINCOLN LOGS A GIFT FOR ALL THE YEAR $1 - $2 - $3 - $4 Build as Daniel Boone and “Abe” Lincoln built Boys! give your engineering and mechan- ical ability a chance. With LINCOLN LOGS _ can build stations, Trestles, Grain Elevators and Coal Tipples for your Trains — Filling Stations and Garages for your trucks and tractors— Barns and Fences—Blockhouses, Forts, and Carag to “go with” indoor and outdoor Pio y. Youcan also make Bird Houses, Flower Baskets, Letter Boxes, etc., to give your friends. BIG COMBINATION ‘SET of 234 logs, $ 4 2 roofsandchimney ....+-e « « TRIPLE SET of 166 logs, 2 roofs and $ 3 DN @ 6 60 6 © © 6 0 © 0 8 DOUBLE SET 110$2 SINGLE SET of $7 logs,roof,chimney, 53 logs & roof, No Delivery Charges — A Design Book in each Set SEE YOUR DEALER or mail | coupon LUNCOLN LOGS Room31, 232 E. Erie St., Chicago, Ill. Please mail at once, postage prepaid: (] Big Combination Sets, 234 logs, etc. @ $4 Triple Sets of Dot ble Single 166 Logs @ $3 Sets @ $2 |_J Sets @$1 Enclosed is fo Logs ported. Money nd to refunded if not satisfactory. Name POPULAR SCIENCE MONTHLY ee 66 ” Cave-In (Continued from page 129) near the bottom of the wrecked “G” shaft, Hawes, Olson and Erickson were pinning their faith on the plan of boring and climbing upward. In the beginning, Hawes had suggested this plan, after he had studied a chart of the Pabst mine. “It could be done,” others had agreed, “but you’d still be a thousand feet below them; they’re on the eighth level.” “The fallen rock isn’t packed tight in the shaft,’’ Hawes had replied. “Cut a hole big enough for me to crawl through to a level where the shaft is open, and I'll find a way to climb up through the shaft from level to level.” HAT was on Saturday. Erickson took charge of driving the vertical tunnels up from the twenty-fourth level. It was extremely difficult. The passage was made about three feet in diameter. Only one man could work in it at a time, and he was compelled constantly to brace the shaft as he progressed, to prevent a cave-in. At intervals, as they bored from level to level, the rescuers tapped the main shaft to learn whether or not they had passed beyond the obstruction. At the twenty-first level it was. still blocked; but beyond the twentieth it was clear. It was then that Hawes made good his promise to “find a way to climb up through the shaft,” and was finally re- warded by grasping the big hand of Tom Trewartha and receiving the joyous greeting of his men. During the days of imprisonment, Trewartha had proved that he, too, was a safety expert, trained in the science of rescue. After the cave-in he had led his men to the task of bracing the entrance to the eighth level with steel rails and timbers, to guard against further cave- ins. Then, gathering his men about him, he laid plans for escape. By this time the three “road monkeys” stranded in the thirteenth and eighteenth levels had climbed up the shaft ladders to join the others. DDLY enough, Trewartha’s schemes of escape coincided almost exactly with the expedients devised by the rescu- ers, and he and his men attempted every one of them. First, volunteers tried climb- ing down the shaft, then up. There was no, way out. Then they tried to break through to the abandoned “C”’ shaft. Finally they attempted to dig a tunnel through to the Aurora mine, little dream- ing that rescuers were digging toward them from the other end. For the final act in the rescue, every- thing had been prepared by experts hours in advance—food, hot drinks, warm blankets, doctors, nurses. At the bottom of ““H” shaft elevators were waiting to carry the men to the surface. And above, on a siding close to the pithead, stood one of Uncle Sam’s mine rescue cars with complete first-aid equipment. It had been rushed to the scene from a town in Wisconsin. So, by the methods of science, the lives of forty-three miners were miraculously saved. 1S] This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. December, 9% Ship Model Plang and instructions. and sell models. meaty te bral pb ragga s “Half Moon a —Clipp 82c—Santa . $1. $1.02 Eiicate Ship, 52e—al th SEA ARTS GUILD 405-N ELEVENTH AVE. MILWAUKEE, Wig SHOOT ARROWS « ~~ New invention shoots farther, harder, more accurate. ly than a bow, any pull desired 10 Ibs. to 80 hee Ibs., kil a deer, fish; a@ real weapon all members of tig enjoy; complete outfit, RUBBER Ss METAU TIPPED FEATHERED ARROW and QUIVER Hog PAID $1. extra arrows ioc each, write for catalogue, BBER ARCHERY CO . 1130 S. San Fernando Bivd. » Glendale, Cal, — BOOK FREE Send now for this interesting and profit ~jable 1 book telling how a beginner cared IN smal in : Rnckyars when at school with no money plant, ae ° N fis 150" barrels quae yearly wanted. rrel. You can do the same. Pri Pics ot beat Jed we val mail it oy 7 esi se gy See A ce ten of four of your rien ‘or Boo PLYMOUTH ROCK St “SQUAB. "C8, 646 S16 os St., Melrose Highlands, YOU CAN DO IT: Famous Violin-M Sells Full-Sized od terns and Illustrated Instructions. Fine woods and other sup. plies Seatenels Mich, Cc. C. FRASER, 625 Stark St., ~ SRIES WE'LL SWAP You ar a =7> oF ge one the Lg $3.75 vostoais ie Police! Ww. nd say, iolks e got the Or slickest films at oliks! We've ale rices—and what’s ey now havea Bim ¢ exchange don that’s Paramount Mts. poe Box 1371 Dept. PS 10, Boston, Mass. U.S.A, DEAFNESS IS MISERY GOOD HEARING A JOY Millions of people know that, but Multitudes of R persons with defective hearing and Head Noises & are again enjoying conversation, go to Theatre and Church because they use Leonard Invisible Antie septic Ear Drums, whicb are Tiny Megaphones fictingin the Ear entirely out ofsight. No wires, 00 batteries, no head piece. They are Unseen Comforts and inexpensive. Write for booklet and swom statement of the inventor who was himself deaf, A. 0. ). LEONARD, Inc., Suite 144 70 5th Ave., New York 21 Jewels Nothing! than 21 Ruby and hire jewels — fe good enough for Burlington pane Y Own a CORONA The portable typewriter built like an office ma- chine. Has four-row key- board and big- machine Ip Re Nev shaf Ws. fg _” 86 2 Vm (A= a AS a features throughout, Write to L. C. Smith and Corona Typewriters Inc, 733 E. Washington St., Syracuse, N. Y See page 6.

Page 129

iE ere TFSFE OO a8 Ea | = & VE esate Se] Baker: 2 = J = egaizredré December, 1926 POPULAR SCIENCE MONTHLY INGERSOLL Wrist Watch Recently reduced to..$ 0 New model this year. Tonneau- shape; silvered metal dial. Wrist ra Radiolite,tellstimeinthe dark,$4.00 Sugersow, When you give an Ingersoll watch you make a gift that is appreciated all out of propor- tion to its cost. For there’s no gift like a watch, nothing used so much, consulted so often, carried so long. And Ingersoll Watches, made for over 30 years, have a reputation for dependability and enduring service that is worldwide and thoroughly deserved. \\ Incersott Watcu Co., Inc. 7 New York Chicago San Francisco \ i (s$s§s§s§WY rT The New YANKEE Recently reduced to More closely cased, antique bow and crown, new dial and = other new features of grace and beauty. Sturdy and de- pendable, iN Own Cards, stationery, labels, paper, circulars, tags, menus, book etc. Save money and time, cut cost in half. Sold direct from factory. , Pays for itself in a short time. ‘ Complete Outfits, $8.85 up. tp Job Press, $11, $29; Rotary $149. Print for Others, Big Profits. All easy, rules sent. rite for catalog of presses, type, paper, cards, envelopes, paper cutters. The Kelsey Co., P-33, Meriden, Conn. EXcersioR Advice for Popular Science readers regarding safe and profitable investments. See page 4, Your Feet and Shoes (Continued from page 18) have a short Achilles tendon, so that, for her, the proper shoe had a heel of more than medium height. In her case the low heel merely made additional trouble. Style and the construction needed to remedy unusual foot conditions cannot always be combined. And when con- fronted with a choice between painful feet and a specially made corrective shoe, most women prefer the pain. One day the wife of a department store manager entered the salesroom of a corrective shoe company. Her feet had been giving her extreme pain. She had come, under protest, only on the orders of a foot specialist. She was twenty-eight years old, modishly dressed, and more than ordinarily attractive. The shoe manufacturers gave particular attention to her needs. She was on the verge of serious foot trouble. They selected for her a firm, rather round-toed shoe that looked like the ordinary well-made walk- ing shoe in all respects except one—it had an unusually long, low heel. It was that unusual heel that aroused the lady’s most strenuous objections. She burst into tears and refused to wear it. UT three days later she was back— with her husband. The husband- manager was a little set around the jaw. His wife put on the shoes. She admitted they made her feet feel better. She wore them out of the store. And the end of the story? For several months the lady wore those detestable shoes. Her feet got better. As soon as the pain was gone she threw the shoes away—and went back to wearing regularly the styles that had made the trouble in the first place. Though an arch support gives relief, it does not in itself effect a cure. In the military service, arch supports are not permitted. The cure for fallen arches is to build up again the strength and elasticity of the muscles in the sole of the foot. After about three months of wearing should be re-fitted. This is because the muscles get a chance to develop after being given plenty of room. The second fitting will usually last indefinitely. Permanent improvement comes slowly. The wearing out of at least one pair of properly fitted shoes ordinarily has to come first. EXT in importance to wearing the right shoes is proper walking. Don’t toe out! Toe straight ahead, or even (if you have fallen arches) slightly in. Avoid undue strain or long walks on hard pave- ments. One physician suggests that people unable to get away from city pavements try walking frequently along the cracks in the sidewalk, putting one foot directly in front of the other. This necessitates a certain amount of balancing that tends to strengthen the muscles in the foot, and, in addition, throws the weight to the outer edge of the foot. Next, almost as important as proper walking, comes proper resting. A good rest is the first step in starting remedial treatment; this an arch support may give. Weak (Continued on page 132) proper shoes, foot experts tell me, feet |: © This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. Lowest initial cost! Lowest upkeep! No garage bills! No traffic delays! Always on Time —and you save money with these two pals INDIAN PRINCE 4 fe THE SOLO SINGLE INDIAN PRINCE - INDIAN SCOUT The Solo Single THE SOLO TWIN You, can learn to ride it in 5 minutes. Wi beaslavetostufly, Light yet sturdy.90 crowded trains and | Miles per gallon . Less than ic trolleys? Hop on one of oon inile Operuting these famous Indian Pals | cost. and knowthe comfortand | Price with com- convenience of zippy pod nde nag healthful-outdoor motor- | F. O. B. Spring- ing—at less than carfare | field, Mass. cost. Acenta mile or less. Motoring with a “kick” Easy handling — perfect balance — restful comfort — snappy getaway — lightning-like pick-up — and all the speed and power you want, at your finger tips. That’s motoring at its best. That’s what you get in the Indian Prince al \- and the Indian Scout. INDIAN SCOUT The Solo Twin Easy to own Twin-cylinder ; price on —_ Let your nearest Indian eration and power: Scien uxemmoes Dealer demonstrate the Indian Prince and the In- dian Scout and tell you about his convenient pay- as-you-ride plan. Mail coupon below for free illustrated catalogue de- scribing these two famous @ Indian Pals. DEALERS: A few good territories open. Our proposition is a winner for ambitious men. Write now. DEPT. H-12, SPRINGFIELD MASS, ition a a YY INDIAN MOTOCYCLE CO., Dept. H-12 Springfield, Mass. “ - O Send me your illustrated Catalog describing the Prince and the Scout. O Check this if you are interested in our money-making proposition to dealers. and safety. 65 miles per gallon gas. 1c per mile operating cost. Price with com- plete electrical equipment $285 F. O. B. Spring- field, Mass.

Page 130

132 A Lyon Healy Saxis easy to learn to play! My son gets one for Christmas-Noah Beery

“Give me the clear, mellow tones of a Lyon & Healy Seen. I like the looks of the instrument, its 1 simplicity, its strong construction. And it’s certainly easy to learn to play! The sax is great for boys, too. Every boy wants a real, man-size saxophone. My son ‘Pidge’ gets a Lyon & Healy Sax for Christmas. ea Bary Noah Beery, the swashbuckling Sergeant in Famous Players’ “Beau Geste,” and other fea- ture films, knows from personal experience that the fellow who gets ahead is the one who can do things. That’s why he is giving his own son (pictured here with Wally Reid’s boy) a saxo- phone for Christmas — starting him right cn the road to pleasure and popularity. What accomplishment have you? Do you play the saxophone? No matter what your age we can teach you quickly, easily, Why envy the other fellow his good times, popularity, leisure, extra spending money, when you can enjoy the same things, too? Easy to Learn Our Way You can quickly learn to play a Lyon & Healy Sax- ophone because——with sixty years’ musical experience to guide us—we have simplified the fingering, made it easy for you to play, easy to produce full, rich tones, The Lyon & Healy is the choice not only of noted amateurs like Wm. Haines, but of leading pro- fessional players as well, because of its extremely ac- curate adjustment and epreeenents in key- action for hair-trigger finger work. Experts are amazed at its new and amazing beauty of tone. Warm and so- norous as the human voice, crystal-clear and true to itch —no other sax can < goto it in tone quality. temember, itis made and guaranteed by the most famous music e in the world! You Can Pay as You Play Now you can own one of Manyearnenough playing these wonderfulinstru- for dances and parties to ments and payinsmallin- meet their payments. Mail stallments, at the rate of the coupon today for full only a few cents a day. details. Don’t delay! Free Trial! Free Instructions! Learn about our FREE Trial and FREE Instruc- tions offer! Discover for yourself the advantages of our special “‘Easy to Pay While You Play” plan by mailing this coupon today! » popularity, friends, money, travel are yours when you playa Lyon & Healy Sax. Let us teach you quickly, easily. Act now! Lyon & Healy Everything Known in Music 249 South Wabash Avenue Chicago saxophone playing, FREE! its opportunities for pleasure and profit, told frankly in this fascinating book. Send fora FREE copy today! Mail the Coupon Today ! LYON & HEALY, Inc., Factory Sales Division 249 S. Wabash Ave., Chicago Please send me FREE, details of your ‘‘Free Trial, Free Instructions offer,’’ your “‘Easy Payment Plan,”’ also a copy of the new Saxophone Book. The real facts about

POPULAR SCIENCE MONTHLY

Your Feet and Shoes (Continued from page 131) feet can be helped by being given every available opportunity for relaxation. A good position is to sit with the feet crossed, resting on the outer edges of the shoes. This allows free circulation, full relaxation, and a complete change from the walking position. It’s not particularly elegant, but it’s comfortable and healthy. And at least it means you look at ease, like a camp stool. Finally, proper exercises and care of the feet are necessary. Two or three minutes a day devoted to foot exercises just before going to bed will usually accomplish wonders. Move the feet about in every direction; wiggle the toes. Try to pick up marbles with your feet. Walk along a line in the carpet, throwing the weight on the outer edges of the bare feet. Nails should be cut straight across instead of round, as finger nails are. OLD water tones up weak feet. One mistake that many people make is to put aching feet in hot water. That tends to weaken the muscles and ligaments, though it may give temporary relief from pain. The proper treatment is the exact opposite. Just before going to bed put the feet, for a few moments, in cold water. That tightens them up, strengthens and revitalizes them. A brisk rub will quickly bring them back to warmth. Alternating hot and cold water, changing quickly from one to the other without giving the feet a chance to soak, also frequently gives good results. Massage helps weak feet by stimulating the blood circulation that builds up the muscles. Such feet should be kneaded and rubbed with the hands night and morning.

‘It’s Brains Against Brains — Fighting Gorillas!” (Continued from page 13) a booming, echoing noise like a big drum. “The cracking of the underbrush told me that the whole band was after us. Hearing them, the young gorillas we had caught began to squeab, just as I was assembling my motion picture camera in the hope of getting a sensational strip of film. We were in the clearing, and I didn’t expect the gorillas to come out from the cover of the trees, but hoped they would come near enough to the edge of the woods to enable the camera to picture them. “Gorillas think much like humans; they weigh their chances and do not plunge headlong into danger, as do the elephant, lion, rhino and buffalo. Against a showing of superior force they usually take it out in roaring, unless enraged to the point of uncontrolled ferocity when their young or family is threatened. And, I suppose, they give humans credit for being as strong as they are, the two races, man and gorilla, resembling each other in so many other ways. Otherwise they would never hesi- tate to attack man, I am sure. “T had three (Continued on page 133) December, 1% Statement of Ownership, Management etc., nomeeires by the Act of Congress of Atiguat Si of Popular Science Monthly, published monthly York, N. Y., for Oct. 1, 1926, State of Nowe County of New York, ss. ‘Before me, a notary pune and for the State and county aforesaid, perso alle ta peared O. B. Capen, who, having been duly nally ap. cording to law, deposes and says that he is the Boat Manager of Popular Science Monthly and that tess lowing is, to the best of his knowledge and beliet sy statement of the ownership, management, ete oe aforesaid publication for the date shown in thad the caption, —. by the Act of August 24, 1919 em above 11, Postal Laws and Regulations print the ——- 4 this form he] = . on . a e names an resses of th editor, managing editor, and business oe Publisher, Publisher, Popular Science Publishing Co., fer ate, Fourth Avenue, New York, N. Y., Editor, Sumner Blossom, 250 Fourth Avenue, New York, N. Y. Manas. ing Editor, Raymond J. Brown, 250 Fourth Avenue Ne York, N. ¥.; Business Manager, O. B. Capen, 250 Fone Avenue, New York, N. Y. 2. That the owners wt Popular Science Publishing Company, Inc., 250 F are: Avenue, New Yor Y. Stockholders of Popul Science Publishing Company, Inc., Henry J. Fisher 2 William Street, New York, N. Y.; Oliver B. Capen ‘oh Fourth Avenue, New York, N. Y.; Robert Cade w: 683 Springfield Avenue, Summit, N. J.; L. B, N. Michigan Ave., Chicago, Ill.; A. L. Cole, 250 F Avenue, New York, N. Y.; Godfrey Hammond 250 Fourth Avenue, New York, N. Y.; Sumner N, Blog 250 Fourth Ave., New York, N. Y.; John Nichols Fourth Ave., New York, N. Y. 3. That the know bondholders, mortgagees and other security ‘ho owning or holding 1 per cent or more of the total amount of bonds, mortgages, or other securities are: none. 4 That the two paragraphs next above, giving the names of the owners, stockholders and security holders, if any, contain not only the list of stockholders and security holders as they appear upon the books of the company but also, in cases where the stockholder or security holder appears upon the books of the company ag trustee or in any other fiduciary relation, the name of the or corporation for whom such trustee is acting, is gi also that the said two paragraphs contain statements embracing affiant’s full knowledge and belief as to the circumstances and conditions under which stockholders and security holders who do not appear upon the boo! of the company as trustees, hold stock and securities in a capacity other than that of a bona fide owner, and t affiant has no reason to believe that any other association, or corporation has any interest direct of indirect in the said stock, bonds, or other securities than as so stated by him. (Signed) O. B. Capen, Business Manager, - ge ie and subscribed before me this 30th day of ept., 1926. Bertha Strauss, Notary Public, New York County. New York County Clerk’s No. 519, New York County Reg. No. 7142 (Seal) My Commission expires March 30, 1927,

SEND NO MONEY Genuine Full Cut Diamonds 2, Terms If Desired—6 Months No. 6132 — Solid Outside U.S. with Order to Pay. Gold Men’s I Cash Py or Emblem Ring, 2 Genuine Diamonds 25 4-100 each. 7 14-Kt. White Gold = Top. Gold Emblem (any Lodge) or an initial(Old English) yellow or white Gold, inlaid in Gen- uine HOPE RUBY Also, in Black Onyz Wy,

New No. 6132 This <j Reg. Trade Mark guarantees you genuine diamonds.

No. 6598. Any initial (raised gold) or Eastern Star, Rebecca, Mason, Shrine, K. of C. emblem instead of initial if desired. Send number of ring, size of Ww 4 finger, initial or emblem desired and No. 6598 — ting will be sent for inspection. Ladies’ Ring Ask for Free Catalog Genuine

Buffalo Jewelry Mfg.Co, Black Onyx with “*The Wtail-Order House”* Genuine Full Cut Dept. A (or at Your Jeweler’s) Diamond. 14-Kt, 501 Washingtoa St., Buffalo, N.Y. White Gold. é

THE PERFECT GRID LEAK a) Provides a noiseless range of grid leak resistance from VY to 10 megohms. Assures most effective grid leak resistance ® value for all tubes. Small grid conden- ser (0.00025) is sep arate. Metal parts nickel plated. One hole mounting. Aljen-Beadley Co. Electric Controlling Apparatus 293 Greenfield Avenue Milwaukee, Wis.

“in

ees

© This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

—s = ee

Page 131

Fj » FESEE.=. EH PAL 2 & BEE LEE es eb? heel in) SS ‘Ss 5 vith Cut Kt. December, 1926 — e a «Jt’s Brains Against Brains —Fighting Gorillas!”’ (Continued from page 132) ‘oc with me this time. To one, the carer, I turned over the crank of he camera with instructions to keep turning until I told him to stop. flanked by the other two, each carrying a squirming gorilla infant, I advanced toward the place where the shaking of the shrubbery and the roaring of the beasts told me the band was assembled. “They kept up a continuous thunder of drumbeats as we approached, but I couldn’t see a single gorilla through the dense underbrush. ‘The racket finally became so threatening that my two natives bolted with the captives. And that, it seemed, was what the ‘old man gorilla had been waiting for. I was alone. “fT JE CRASHED toward me through the underbrush, a huge, hairy, tow- ering bulk, walking erect, almost like a man, with his great arms hanging to his knees. Nowondertheunarmed nativesfear the gorilla. But that was an afterthought. “T fired once. He was so close that I could not miss. He fell dead, almost at mv feet, and the rest of his family fled into the forest. “As he! lay there, in the crater of the ancient voleano of Mikeno, I measured him. Six feet tall he had stood in life. His foot was twelve inches long; his fist when closed would have filled a gallon measure. I estimated his weight at 450 pounds, and do not think that is exaggerated. His muscles stood out in great knots, indicating his tremendous strength. “He seemed so human, like some pre- historic ancestor of our own race, that if [had gone into the gorilla country for the sport of killing them I believe I would have abandoned my expedition then and there. But I was on a scientific mission this time, and the skin and skull of that monster are now being mounted in the National Museum at Washington, the only specimen of the full grown Kivu gorilla possessed by any museum.” While he was talking, I had noticed that Mr. Burbridge rubbed his left hand frequently. Now he caught my glance and held his hand toward me, so that I could see the scars upon it. “rTSHOSE are mementoes of one of the most exciting experiences I ever had with a gorilla,” he explained. “I deter- mined to try to get at least one live gorilla larger than the babies which had pre- viously been the only ones captured. The one I picked was a male, perhaps seven or eight years old and weighing one hundred and twenty-six pounds. “I got him, the largest gorilla ever taken alive. But after the battle a survey of the field showed two fingers broken on my left hand, the left thumb mangled, both hands lacerated where he had used his teeth, and half a dozen of my natives lying around, mauled and bitten. The underbrush had _ been trampled flat in the struggle. A bloody trail led off into the forest, left by another gorilla who had tried to interfere but had been shot by my (Continued on page 143) Wilson Common-Sense Ear Drums require no medicine but effectively replace what is la ing or defective in the nat care Where they are invisible, Soft, safe POPULAR SCIENCE MONTHLY 133 30 Days FreeTrial Yes Sir! SA You can put a new 1927 Westingale Radio in your home and use it to your heart’s content on 30 Days’ Trial. Listen to music, concerts, news, sports, market reports from stations all over the country. Compare it with old style 3 or 4 dial sets costing more, then if not convinced that West- ingale gives you the greatest Radio satisfaction and the best value for your money, you don’t have to keep it. NOW! Westingale offers the last word in Radio. Either 1 or 2-Dial Control —easiest to tune and years ahead in powerful reception and tone. Newest period type cabinets, two-tone walnut finish. The front anel embossed in dull gold with artistic Spanish Galleon design. Un- atable for performance, appearance or price. Sw, 2-Dial, 5 tubes $47 a a ' > 1-Dial, 5 tubes57% === .. — : D ’ S ; vA Nw «Where else can you get so much for the Nw money on 30 days trial? y pay more? Wy take chances? Why not have the “a NEWEST Radio when you can try them ™ at our risk. Before you buy Ay our Free Catalog and 30 Day Trial Offer. Bi Westingale Electric Co. 4 Department “ 1751 Belmont Av.,Chicago, Ill. Your own Radio Free. Get demonstrator 8 WANTED set on 30 Days’ Trial—make up to $100 a week easy. Full or spare time. Big discount on first set placed in each locality , deal: iscount and full details, Deafness Tells how you can make big money in world’s newest and greatest field. Presents lifetime opportunity in Radio. Right now we want live agents and dealers in every locality; up to $100 a week easy. or ear drums. They which the wearer easily fits into the comfortable. book explaining liberal profit proposition and how to get latest radio goods at Free Book on deafness giving ag full partic= ice ulars and man timonials. th ds of on Deafness) Te hearing of thousand sets and accessories and amazing stored by these “little wireless phones 1 special offers-all free. Write today. STANDARD RADIO CO. 1404 Walnut St., Kansas City, Mo. WILSON FAR DRUM CO., Incorp —, , ti 86 Todd Building LOUISVILLE, KY. This Full-Floating Rotor Shaft Adapts the New Hammarlund “MIDLINE” To Any Condenser Arrangement It may be adjusted, without cutting, to accommodate various types of dials, or replaced by a longer shaft for gang-operation of two or more condensers, or for mounting a variable primary coil. Gears, cams or pulleys for any desired method of single- control multiple condenser operation can easily be attached. wi Complete Separation of all Wave-Lengths The New Hammarlund “‘ Midline” Condenser does not crowd either the upper or lower wave-bands and retains normal separation in the middle of the scale. Made in all standard capacities, single and multiple models, embodying every refine- ment developed during 16 years in the production of electrical precision instruments. For sale by the good radio stores. HAMMARLUND MFG. CO. 424-438 W. 33rd St. New York City Jor Bottor Radic’ ammarlund PRECISION PRODUCTS © This seal on a radio, tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 132

POPULAR SCIENCE MONTHLY FREE RAILROAD FARE TO CHICAGO WHEN YOU ENROLL Learn Electricity in 12 weeks at Coyne Students Doing Actual Work Power Transmission Apparatus P =—_ af | PUTA ea ea JR oe ea ‘if % a Pie ee Students Working on Massive A.C. Control Equipment. aang Students Practicing House-wiring in Skeleton Houses Send for the Big Free Book which shows the Great School of Coyne and a of our massive elec- trical equipment. You will be convinced that the only to get a practical electrical training is in the reat School of Coyne. Many Earn $6§ to $200 a Week! Or Go in Business for Yourself and Make up to $3,500 t0 $15,000 a Year Yes, 12 weeks at the Great School of Coyne, located in Chicago, The Electrical Center of the World, will enable you to become an Electrical Expert capable of commanding big pay. The whole world of electricity is open to the practical man —the man who has had actual experience with electrical apparatus. Coyne gives you a practical training on the greatest out- lay of electrical apparatus of any institu- tion in the World, everything from door- bells to power plants. You Can Become an Electrical Expert We don’t attempt to teach you by lessons or ks. Weteach you by practice on our mam- moth outlay of actual equipment. We train you in house-wiring by having you do it exactly as it is done outside—not just by reading about it. The same applies to armature winding, power plant operating, motor installations, automotive work and hundreds of other electrical jobs. That’s why we can train you to become a Master Elec- trical Expert. No Books—No Lessons —You Do Actual Work The Corns practical course includes no books, printed lessons or useless thebry. We train you to work with your head and hands on the same kind of electrical apparatus as you will find “‘out in the field”. Age, lack of experience or educa- tion is no drawback. Our students range from 16 to 60 years of age. Coyne gives you Free a Life Scholarship which enables you to stay as long as you want without extra charge or return later for more training, and assists you to a position after graduation. We also include Free a course in radio and auto electricity, and pay your railroad fare to Chicago. Earn While You Learn! We help students to secure jobs to earn a good part of thew living expenses while training and assist them to a big paying job on graduation. Send For Free Book, Fill In And Mail ToDay H. C. Lewis, President Coyne Electrical School, Dept. 96-73 1300-1310 W. Harrison St., Chicago Dear H. C.: P!.ase send me your free big catal particulars of your special offer which includes ‘Tree Rail- and full H.C. Lewis Founded Fare to Chicago and two extra courses. P. 50! 1899 Se ~ al Name k nidorecd by Electrical Industry Address....... 1300-1310 W. Harrison St., Dept. 96-73 Chicago bbe $25 in, CASH PRIZES For the best letter of 170 words or less answering the question— ‘‘What advertisement in the ‘Money-Making Op- portunities’ Section inter. ests you most—and why?” we will pay on January 10th the following— CASH PRIZES First Prize $10.00 Second Prize 5.00 Third Prize 3.00 Seven Prizes of $1.00 Each 7.00 First read every advertisement in the Money-Making Oppor- tunities Section on pages 134 to 165. Pick out the one that in- terests you most and then write a letter—not exceeding 170 words —telling us why you find the advertisement you have selected the most interesting. Entries for the contest will close on December Ist. The prize winners and their letters will be published in the February issue of POPULAR SCIENCE MONTHLY. Address your letter to Contest Editor MONEY-MAKING OPPORTUNITIES POPULAR SCIENCE MONTHLY 250 Fourth Ave., New York PRIZE WINNERS in the October Contest FIRST PRIZE $10.00 Alfred Alter, Bronx, N. Y. (American Sch. of Aviation) SECOND PRIZE $5.00 Ben F. Statum, Knoxville, Tenn. (Coyne Electrical School) THIRD PRIZE $3.00 C. Fredk. Morris, El Reno, Okla. (National Salesmens Training Assoc.) PRIZE WINNERS who receive $1.00 each for their letters: O. F. Sternemann, Hawi, Hawaii (University of Chicago) Mrs. L. E. Davis, Springfield, Ohio (G. & C. Merriam Co.) Dorothy Keeling, Somers, Mont. (American School of Aviation) F. Gruver Davis, Springfield, Ohio (McGraw Hill Book Company, Inc.) Robert L. Stewart, Long Island City, N.Y. (Tarbell System, Inc.) E. C. Greene, Gallipolis, Ohio (International Corres. Schools) N. D. Childs, Cleveland, Ohio (International Studios, Inc.)

Page 133

$475 a Month Dear oe I have Jost foabout $79 amonth si aweek. Before Wittenbe Bronx, New _ MONEY MAKING OPPORTUNITIES SECTION come now amounts $150 a Week Dear Mr. Cooke: Thought you would be inter- ested in a hand bill I just got out for my new shop. Business is going strong, paying me now over $600 a month above expenses, I mus thank you again for my success, because “a it was your wonderful Course and method of amd jon that that put me where I _ aa Pence, Albany, O;: There's a Place for You Too in This Big Pay Field Electrical Experts Needed Everywhere — Let Chief Engineer Cooke Train You Right at Home ALL it luck—Call it “bunk” —Call it anything you like —But these two and thou- sands of other Cooke Trained Electrical Men are earning this big pay. They earn from $3500 to $10,000 a year and the same road they took is open to you— Now! Why stick to your no-future $25 to $30 a week job when these thousands of men no smarter than you and with no previous expe- rience are jumping ahead of you— easily earning two to four times what you earn, year in and year out: Electricity needs you. It has a place for you and thousands of other red-blooded, honest-to-goodness young fellows who wantareal joband REALMONEY and who have gumption enough to trade a little of their spare time for a chance to get it. Electricity is the world’s greatest business. Over 750 million dollars are being in- vested in it every year. In the power house end of the industry alone, 15 thousand new and addi- tional jobs were created last year. Electricity is an opportunity—a future—‘‘Success”—for thousands of men. Will you risk two pennies for a stamp to find out what it will do for you? Chief Engineer Cooke has written a wonderful book about electricity, its opportunities for. young men, and what these opportunities mean to you. It is printed in colors, has 64 pages and more than 100 pic- tures. It’s the same book that Chief Engineer Cooke — The man who has trained and helped many thou- sands of other men into big pay elec- trical jobs in all parts of the world. Mail Coupon for his big free **Book of Facts*® started more than ten thousand other men on the road to big pay. It’s free—and it may help you like it helped them. Anyway send for the book and decide for your- self. No agent will call on you— no one will bother you and you won’t be obligated in any way. What you do inthe next minute may mark the turning point in your life. Mail the Coupon Now, to— L. L. Cooke, Chief Engineer L. L. Cooke School of Electricity conn tn and Operated by ring Works INCORPORATED 2150 ice Ave. Chicago, Illinois RG AO TTS SS SORES L. L. Cooke, Chief Engineer Dept. 39, 215¢ Lawrence Ave., Chicago, Illinois I want the proof. Send me your free book on Electricity and other information ote your training and — service so can decide for myself. I understand this is te be sent to me by mail—not by an agent.

Page 134

MONEY MAKING OPPORTUNITIES SECTION cAdding Machines FREE trial. Marvelous Calculator. Adds, Sub- tracts, Multiplies, Divides automatically. Work equals $300.00 machines. Five year guarantee. Price only $15.00. Write today for rd trial offer. Special: $3.0) Pocket ets only $2.00 cash. htning Calculator Co., Dept. O, Grand Rapids, Mich. Advertising Services ADVERTISE in 24 metropolitan dailies, 24 words, $15.00. Helpful Guide ee 1000 eee. 4c stamps. Wade Company, Baltimore Bldg., Chicago. 24 WORDS,-151 rural weeklies, $6.04. 4112P Hartford, St. Louis, Mo. COPY that gets orders—Folders, ——. etc., that pull. Hewson, City Centre Building, Phila. ADVERTISERS’ International Manual, new edition. information for advertisers and Publishers’ Rates. 50c Postpaid. Economies Publishing Co., (Dept. 54), 1475 Broadway, New York. ADVERTISING in all magazines and newspapers at publishers’ lowest rates. Write for Rate Book. Taylor's Advertising Service, 314, Brown Bldg., Rockford, Illinois. SILVER quarter gets 2 good classified ads and replies = list 55 southern country papers. Write. Wilson, 0x 243, Michigan City, Indiana. Ad-Meyer, Authors and Manuscripts $$$ FOR Ideas. Photoplay Plots revised, criticized, copyrighted, marketed. Send for free booklet. Universal Scenario Company, 238 Security Bldg., Santa Monica & Western Ave., Hollywood, Calif. Rates 30 Cents a Word. A 10% discount is allowed on all contracts for six consecutive inser- tions. Advertisements intended for the Feb., 1927 issue should be received by Dec. 5th. Business Opportunities STOP plodding! Be successful. Operate a tire repair shop. Make big profits in any locality. We teach you and furnish complete equipments, $100 up. Book of Oppor- ss free. Haywood's, 1306 South Oakley Avenue, cago. Business Opportunities I MADE $30 a week home. French br years’ experience. Free booklet tells. Pri 3 15 EAGT, Marengo, Ohio. Chemicals Free with Order, GETIT! Test it! Rae’s Process of Silvering Mirrors. Write Rae’s Mirror Works, Amherst, Nova Scotia. MONEY Collecting Selling Names Plan 50c, 4 Barnes, Helena, Ark. Blue Prints — PATENTS procured; Trade Marks Registered—A comprehensive, experienced, promeet service for the pro- tection and develo opment of your ideas. Preliminary advice gladly furnished without charge. Booklet of in- formation and form for disclosing idea free on request. Richard B. Owen, 44 Owen Bldg., Washington, D. C., or 41-Z Park Row, New York. WE Start you in business, furnishing everything. Men and women, Cw ppp y to earn $35 to $100 week- ly operating Ragsdale’s original ‘‘New System Specialty Candy Factories’? anywhere; wholesale or retail. Big commercial candy book free. W. Hillyer Ragsdale, Drawer 19, East Orange, N. J. SCHEMER, Alliance, Ohio, 36p monthly, prints mam- moth $-getters. Subscriber reports $25,000 from three; another $10,000 from one. Try your luck. Year, $1.00; 3 months, 30c. None free. WANTED—Representatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York. TO the man who has a Home Workshop and likes to to work with tools, Popular Science Monthly offers the opportunity to purchase blue prints giving details of the construction of useful articles for the home. The follow. ing are a few of the blue abinet available: No. 1, Se: ‘Fable, No. 5, Kitchen C Pe. No. 13, Tea Wagon, No. 15, W orkshop Bench, No. 17, Cedar and ‘Mahoga any C No. 41, One Tube Radio Set, No. 42, Radio Receiver with three stages of amplification, No. 43, Four Tube Receiver, 44 and 45, Model Pirate Ship, 46 and 47, Spanish Galleon, 48, "Model Sailing Yacht. one 25¢ for each blue print that you wish to Popular Science Monthly, 242 Fourth Avenue, New York, N. Y. Chalk Talks LAUGH producing program, $1.00. Catalog free, Cartoonist Balda, Oshkosh, Wisconsin. “$50.00 WEEKLY mailing form letters. We furnish everything. Samples and particulars 10c. Whitney Co. Station C, Cincinnati, Ohio.” SONG—Poem writers. Address Monarch, Brenda ene 126, New York. SONG Poem Writers—Send for a Ray Hibbeler, D10, 2104 N. Keystone Ave., Chicag SONG Poems Wanted. Ambrose i Write, Box 327, Norwalk, Ohio. I WANT song poems. Racine, Chicago. cAutomobiles and cAccessories DELIVERY bodies for Ford Model T. Chassis with inclosed cab, suitable for Contractors, Grocerymen and Farmers. Three styles. Price $42.60. Write Daniel Zimmerman, Craigville, Indiana. NEW and used auto parts, Save 25-80% Motors, 1472 Casper Nathan, J-3544 No. ea. Radiators, eels, Generators, Starters, Carburetors, $5.00 up Complete Tops $1 , Gears Axles, earings, Nickel Spring Bumpers. Brightman Auto Parts Co., 321 Windsor Ave., Hartford, Conn. HUDSON Owners. We stop Piston Pin Knock, Oil Pumping, Piston Slap. Write for information. Evarts Machine Co., Hartford, Conn. cAviation UP and down profits. Why trace in the stock Mar- om only to profit by an advance or by a decline when ou can trade to profit either or both ways. Free booklet explains. Paul Kaye, 149 Broadway, N. Y MIRRORS fesilvered at home. Costs less 5 cents per square foot; you charge 75 cents. Immense profits, plating like new; brassy worn-off auto parts, re ponern, tableware, stoves, etc. Outfits furnished. Details free. Sprinkle, Plater., 94, Marion, Indiana. SIGNS and Showcards easily painted with Letter Patterns. Large variety of styles and sizes. Write for free samples. John Rahn, D 2120 Neva Ave., Chicago. SMALL fortunes being made in uncrowded Baby Chick Industry. $3,000 to $5,000 first year not unusual. Business keeps growing; apr ge demand. Valuable booklet explains wully, tells what_to do, how to do it. Send 25c to cover mailing, etc. Limited supply—write now! Wellington J. Smith Co., 552 Davis-Farley Bldg., Cleveland, O. FREE folder, start spare time mail order ee. T. Johnson, Box 524, City Hall Station, New Yor MEN—Women: make $20 daily. I did. Baapls Articles, Plans, 10c. Nameyer, Etters, Penna. LIST of 50 German Manufacturers $1.00 (C.O.D. $1.15) Rabb, B2256 Maypole, Chicago. Distributors Wanted WORLD'S fastest selling auto oneery, distributors wanted; write to-day. G. L. Oiler Co., San Diego, California. WANTED—Representatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York. Dogs, Birds, Fish BEAUTIFUL registered bull pups cheap. Bulldogs, 501 Rockwood, Dallas, Texas. HUNDRED Hunting Hounds. Fur Finders. Cat- alog. Kaskaskennels. B-56, Herrick, Ill. HUNTING hounds. Cheap; Trial allowed. Dixie Kennels, C4, Herrick, Ill. a » Spring Education and Instruction CORRESPONDENCE Courses sold complete: 1-3 usual prices because ‘slightly used; easy terms; money back guarantee. All schools and subjects. Write for special Free catalog. Courses bought for cash. Economy I:ducator Service, 202-N. West 49th St., New York. ADVERTISE in 400 country newspapers, 28 words, $10.00. Keator, Hartford Bldg., Chicago. THE American School of Aviation announces a new correspondence course in mechanics of aviation. A thorough training in practical aeronautics. American School of Aviation, Dept. 6741, 3601 Michigan Ave., Chicago, Illinois. THREE-foot mounted propeller _ 25c, Ave., Detroit, Mich LEARN to Fly! W rite for booklet. Robertson Air- craft Corpn., Anglum, Mo. WANTED Ten Men! Interested in earning tuition at aviation school. Send 25c for illustrated booklet and details. Aeroplane Dept., Box 502, Peoria, Ill flying model aeroplanes. 12-inch Aero Shop, 3050 Hurlbut FRIEND Allard writes letters of application that get the position, free booklet, 1217 Mary Ann, Montreal, Canada. MODERN Mail Order Methods. A new book that tells how to operate a mail order business sg a Write for free circular. Patrick-Mahoney Co., P. O. Box 931, Schenectady, N. Y. Be L Your Own Goods. rts. Manufacturing Processes. Formulas by Trade-Secrets. aI kinds. All lines. paamamaaad circulars free. C. Thaxly Co., Washington, D. Byrd— MINIATURE eating machines $50.00. 318 Reed, Erie, Pa. “BIG. Special Christmas Offe..” Curtiss Pulitzer Racer Construction Set. Scientific Airglider. One Year's Subscription Aero Digest. All for $6.00. Canada Extra. Send 5c for Big Model Airplane Boat & Supply Catalog. Phipps Airplane Company, 367 Wilson Ave., Brooklyn, N. Y. Books and Periodicals FUNNY White Mule magazine, including a pocket novelty. 10c. White Mule, Beaver Dam, Wis. AUTHORS: our co-operative plan produces and pub- lishes your book. Meador Publishing Company, 27 Beach, Boston, Mass. Branch Offices CINCINNATI Address. Thompson Service, 818 Oak S WASHINGTON Address, = Monthly. Branch Office and Information Service. Robertson, 909 Investment Building ae Forwarded Daily. Business Opportunities USED correspondence school courses. All kinds. Sold on re-purchase basis. Big saving. Money back guarantee. Lists free. (Courses bought.) Lee Mountain, Pisgah, Alabama. LEARN the collection business. Good income; quick results. Interesting booklet, “Skillful Collecting, ” a Ly Collector's Association, Science Building, New- ark, Oh LEARN to make eomtital statuary bookends, — dars, etc. at home. Big profits for Xmas. Outfit free. a Art Relief Process, 541 North Michigan Ave., CAPITALIST—Wanted. Griffins Patented Propeller Tested— Marine — Aeroplanes, Converts slippage into propulsion. High - Less Revolutions. Griffiths, 62 Sudbury Street, “Boston, Mass. CAPITAL secured for invention, any business propo- sition. Inexpensive, reliable method. Interstate Service, Elizabeth, N. J MANUFACTURE New Fast Selling Novelties, Toys, Preparations, Agents’ Goods. Free list reliable plans, patterns, processes, commercial information. Manu- facturers Bureau, 1129C East 3lst, Kansas City, Mo. ARE os u old at forty? See our advertisement on page 165 of this issue. The Electro Thermal Company, 4064 Main Street, Steubenville, Ohio. AN ATTRACTIVE . peered for competent ceramist and abrasive wheel expert to enter a profitable business. A well equipped plant is looking for an expe- rienced manager and partner. A man with sufficient resources of his own to carry him until the profits are available for distribution. Address—Box 18, Popular Science Monthly. SELENIUM or Photo-Electric Cells. For all pur- ses, very sensitive, quick and permanent in action. ree years guarantee. Send 10c stamps for catalog. te ae ecquaarciegaed Hampton Bays, Long Island, AMAZING Opportunity. Million Dollar Income when Goods Nationally Distributed. Capital wanted Launch Manufaciure. Business already established. Article used in nine-tenths American Homes. eal Merit. Constant Demand. Write today. Box, 935, Atascadero, California. BECOME a Foot Correctionist. A New Profession not medical nor chiro 7. fe the trade you can attend to; Many ar> a $10,000 yeasty. —s terms for training by mai ether Sepical nood oods to buy, no icy Or sahetting. Address Gapbetaee bora- tory, m0 ack Bay, Boston, Mass. EASY Sales—Quick Profits.—Dilute our concentrated materials for making high quality foods, beverages, ex- tracts, toilet and auto specialties. Market under your brand or ours. Labels and containers furnished. Per- manent, Bio eo exclusive. D-B Concentrating Co., Station E-19, Kansas City, Mo. CORRESPONDENCE Courses. All Schools. Lowest prices. Terms. Catalog Free. Mention Subject. Fred Goetz, 440-B Sansome, san Francisco. STUDY Microbiology, Earn $300.00 Residential and kExtensicn Course in Bacteriology, Sanitation. Diplomas, Degrees granted. 71-Piece Urinalysis Outfit Free to Students. Write for Free Prospectus today. Internationa] College of Microbiology, 7208 West Grand Ave., Chicago. “DOUBLE entry ot aoe mastered in 60 hours with 8 keys; guaranteed; d Og ane Book- keeping Institute, Desk 10 Po oringfeli BOOKKEEPING ina — $2 ie “Dukes, 640 West 153d Street, New Yor “PITMANIC” Light- cine Saniaiameaian Book, 250. 25¢. Marr, Teacher, Nashville, Tenn USED Correspondence School Courses and Educa- tional Books bought, sold, exchanged; Bargain Cate logue Free. Hanfling, 799-X Broadway, New York. EVER called upon to ag before an Audience? Speeches, aw 8s, Debates. Any —- Write for circulars. E. A. Raiche, Neenah. HIGH Secor Bookkeeping, Biarennd. Typewritin, Normal, Civil Service, Business Efficiency, Law, an over 100 other courses thoroughly taught by ‘mail. Positions guaranteed to graduates. Address Carnegie College, Rogers, Ohio. DON’T prepare for any Civil Service examination without seeing our free catalogue. Columbian Corre- spondence College, Washington, D.C a Month, Electrical Eh ag Electrician’s Wiring Manual, By F. E. Seng- stock, E. E. Contains all the information needed for the proper "leuenaiaiaen of lighting and power systems in houses and other buildings. It completely covers inside electrical wiring and construction in accordance with the National Electric Code. Pocket size—flexible bind- ing. 448 pp. Price $2.50. Popular Science Monthly, 250 Fourth Ave., New York City. : Financing and Investments STOCKS—Bonds, Domestic—Foreign, bought—sold, Dealers in all marketable securities. Frank G. Everett Co., 20 Broad St. New York. For Boys ENTERTAINMENT for Boys! Our latest Movie Machines and durable Steel Toys are just the thing for real play. Catalogue Free. D. F. Elder & Co. Sennen Dept. Dil, P Chelsea, Mass, —-_ © DBD && F&F

Page 135

MONEY MAKING OPPORTUNITIES SECTION { Will Train You At’ Home To Filla» t BigPay Radio Job If you’re earning a penny less than $50 a week, clip coupon December, 1926 Bey PRALAZ?

ing / now. Send for AMAZING FREE BOOK, “Rich Rewards in fs age © Bee yy could earn ays, as xper “I give you all Hundreds of N. R. I. trained men are pecs "it—why can’t aut . =, a Earn up to $250 a Week— ; suickly at home RADIO EXPERTS BIG DEMAND 1: q Radio needs trained men. Get into this new live-wire profession

the seeokiogs

of quick success. It’s the trained man, the Radio Expert, who gets the big jobs of this profession—paying $75, $100, $200 a week andup. Every day N. R. I. trained men are taking good places in the Radio field—men just like you—their only advantage is TRAINING. You can prepare just as they did, by new practical methods. Our tested clear training makes iteasyforyou. Big Free Book contains all the proof.

Foe! ag! e+

r FREE ae a ‘You Learn Quickly _ * | extra In Spare Time =; | cost Reread ag eter -r ed ne

profession, that I guarantee your training - with a money-back bond. Lack of ex- e perience or education won’t hold you

3 Y o GS e back—common schooling all you need @ ey ay t to start. You can stay home, hold WMA - iH a your job, and learn quickly and Bence py position e.. All oe Th Ss pleasantly in your spare time. My the Chica o Daily News Sta | | practical, helpful methods enable tion ATLY DOUBLED you to start RIGHT AWAY to- thanks te vou, 1 handle orf bh Ps migra shown here and '\ ward one of the bigger Radio ing. Your course taught me Y, others sent to all my students free jobs paying $50 to $250 a netonly the theoretical but “4 of extra cost under short time special offer ] mode g Poa no losing time thet makes my — ee y, Clip coupon now—find out all about this big from work —no scrimping or for me.’ Keith i be ena — —_ ae =. have time be scraping to get your training. Station WMAQ, Chicago, uk 7 e advantage of i s training is intensely = practical—these instruments help you do the + = practical work. You learn eo Eo and get Get This F REE BOOK 0 ee panna — in Most amazing book on Radio ever written z —full of facts and pictures—tells all about - World Famous | the great new Radio field, how we prepare ou and help you start. You ' can do what others Training That Thave done-GET THIS BOOK. Send coupon *“*Pays for Itsel£** today—no obligation. ‘ My Radio course World- J. E. SMITH, President , Famous as the training that NATIONAL RADIO INSTITUTE “pays foritself.” Makemore Dept. P.T.9, Washington, D. C. @ money QUICK when you take up this practical course. Work on millions of an- " tennae, receiving sets, offers you big chance 4 to make spare time cash while you're learn- ing. I'll show you how—teach you the latest ope,’’ furnish you with business cards, show you how to get the business and makeitpay. My ss m™ students don’t wait a yeartoincrease theirincome —they report QUICK INCREASES as aresult of $70 In +e Day For this course—often two or three weeks after starting. . M. Wilcox Howard Luce, Friedens, Pa. made $320 in 7 weel:s toss Pate time. D.H. Suite a Rate writes, q “] amin business form lle taki e course I earned in spare time wor. ome RECENT LYM ADE about $900.”” Earl Wright, Omaha, reports making $400 $70 in ONE ay I was an inashort time while taking course—working at Radioin electrician of rich experi- Spare time! Sylvester Senso, Kaukauna, Wis., made $500. , ence, Occupying a splendid hese records not unusual—these men a few of hundreds. Position as telephone su erintendent when I snroll- Your Satisfaction Guaranteed way,send me your free book, isin Radio” : gilesp! will be worth tens YOu when youenroll. On completion if you’ re not entirely satisfied SE. and ail information about your practical, stud of thousands of dollare to in every way, you get back every cent you’ve paid us. No strings te Radio Course. me in ne eare.’’ to this offer—you yourself are the only judge. Get started today! T.M. MW cond Belle tees, sie 's Se big chance for one of the bigger Radio jobs—mail coupon lewfoundland. for my Big FREE BOOK and proof! Nc obligation. POOP E Peres eeererereeeeseeseseeressesesssesss s MEO, se seee EMPLOYMENT SERVICE TO ALL GRADUATES. eee eee ee eee eee eee eee eee eee eee eee ee eee 2 |

COMP C ere meee ees eweseeesseeeresesesess ememGs senesese

Page 136

For Men and Women DETECTIVES—W ork hom. or travel. Lxperience unnecessary. Write, George. Wagner, former Govern- ment Detective, 1968P Broadway: N. Y. BARBER shears corrugated eee grinding. Pe years’ experience. Perfect work, 24-hour service, each. Send prepaid. Fuller, 420 S. Main, Lima, Onto” WANTED—Representatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York.

Formulas CHEMICAL Expert furnishes Manufacturing For~ mulas and Processes with complete working directions. Reliable individual service only. No lists. Charges rea- sonable. Correspondence invited. Dr. Arthur Van- Heeden, 510 South TY Oakley,’ Chicago. MAKE-SELL Your Own Goods. perts. Manufacturing Proces kinds. All lines. Co., Washington, D. C FORMULAS for Tndustty or Business Guaranteed + a ap New Jersey Laboratory. 901 E. 27 St. Pater- son, i ° 500 agg ae Catalog Free, Ideal Book Shop, Park Ridge, Illinoi:

Formulas by ex- rocesses. Trade-Secrets. All vee circulars free. C. Thaxly

For Inventors MONEY MAKING OPPORTUNITIES SECTION Help Wanted Instruction DETECTIVES Earn Big Money. Excellent oppor- tunity. Travel. Fascinating work. Experience un- necessary. “Write eee Ww agpee, former Government Detective, 1968P, Broadway, N. FIREMEN, Brakemen, catered. sleepin monthly. —_ East St. Lo

RX emen, (white or ell train porters (colore’), $150-$250 a. unnecessary. 838 Railway Bureau, December, 19%, Miscellaneous ART—photos 4, p00: lesson, $1.00: outt ere GPO, Box 471, N. sson, $1.00; cuts, ig FORMS to cast rand Soldiers, Indians, Marines tor rs, Animals, 151 kinds. Send i0c for Tiiustrated logue. Henry ©. Schiercke, TO3e 72nd St. » Brooklyn, We UNUSUAL Horoscope Consisting of Exteneeese page Special Horoscope, and Astro O Analy sige eae tk and birthdate. Prof. Bolles, Box 125, Cranf ne

MEN ate Taras ranger, railway mail clerk and es ‘ovt. poane. Write for particulars. Mokane, enver, Colo. aE ADVERTISER: Ask today for a copy of the “Quick-Action Advertising Rate Folder.” It contains some really important facts which will prove ee and valuable to you. It also tells ‘ ‘How You Can Use Popular Science Monthly Profitably.”” You'd like to know, wouldn’t you? Address your inquiry to: Manager, Classified Advertising, Popular Science Monthly, 250 Fourth Ave., New York. RAILWAY Mail Clerks. Month. Travel—See Country. Common education suf- ficient. 25 coached free. Write nome’. Franklin Tnetivate, Dept. D33, Rochester, New York

Men, 18-35. $158-$225

How to Entertain AYS, musical comedies and revues, minstrel uae blackface skits, vaudeville acts, monologs, dia- logs, recitations, entertainments, musical a stage hand ry make-up goods. Big catalog free. T. S.

IF YOU have a practical, useful invention to sell, write Chartered ssociation American Inventors, Barrister Building, Washington, D. C. INVENTOR’S Universal Educator—contains 900 mechanical movements; 50 perpetual motions. Tells how to obtain and sell patents. Suggests new ideas. Explains how to select your attorney und avoid patent snarks. Price (revised edition), $1.50 postpaid. Albert E. Dietrich, 681 Ouray Bidg.. Washington, D. C. UNPATENTED Ideas Can-be Sold. I tell you how and help yeu make the — Free particulars (Copy- righted). Write W. T. Greene, 805 Jenifer Building, Washington, D. C. INVENTIONS Commercialized. Patented or un- ees. Write Aiam Fisher Mfg. Co., 183 Enright, St. uis, Mo.

Co., 623 Boe Wabash, Dept. 26, Chicago.

Incorporations —

DELAWARE Incorporator, Charters: Fees Small; forms. Chas. G. Guyer, 901 O e St., Wilmington, ‘ ‘ M Delaware. " — nate Motion Picture Business ( AN OLD alarm clock can be used in-makine eae Goct: ata, SS en ne sents and instructiong mn fa rite for particulars rt Deibig, neer, 1690 Park Ave., New York. - Electrical Rak PM a a ge a Lang wed a Inger ge beta, vy 8, lariats, horse hair articles. In Co., 319 Fannin, Houston, Texas. Sersol Leather RECEIVE big mail—quarter coin puts name Edw. Fletcher—Box 1071 Camden, N. y ; . on lig, CHRISTMAS Gifts. Hand Colored one—60c, three for $1.20. One larger ins Tre R Butler Nature Prints, Houghton, Mich. ARE you old at forty? See our advertisement on pave 165 of this issue. The Electro Thermal Company, 7 ae Main Street, Steubenville, Ohio. Models and Model Supplies

HULIT & CO., 625 Jackson, Chicago, Ill. Expey. mental Machinists. Model Makers, Dies. Patterns, Complete general Machine shop. “SPECIAL machine builders, tool and die makers, inventor’s models, production work of all kinds. Dept, j Quality Hardware & Machine Co., Ravenswood and Thorndale Avenues, Chicago, IIl.’’

—

Information

RELIABLE information any subject. ocesses. Prompt, accurate service. Fee Formulas, pr $5.00. A. Cook, Information Bureau, Box 952, Los Angeles, Calif.

WANTED—Representatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York. INVENTORS: Get this pamphlet—‘‘What to In- vent.” No theory or guess work, but things poly asked for by manufacturers. Sent prepaid for only $1.00. Inventors’ Syndicate, 23 Paladium Blidg., St. Louis, Mo.

Inventions Wanted

WILL buy approved invention. Write W. L. Kendig, 416 N. Duke Street, Lancaster, Pa.

I AM in touch with hundreds of moneyed men and manufacturers who wish to buy good inventions. Hart- ley, 38 Court St., Bangor, Maine. Laboratory and Chemical Services

“INVENTIONS developed to commercial basis— Se st oe claims suggested —A. Papini, IDEAS for = inventions. Enquiries answered. R. Harvey, 2731 Rose St., Victoria, B. C For the Home HOT WATER ON TAP, $6. Make your own Auto- matic. Write John Kirkeby, San Luis Obispo, Calif. GRANDFATHER og — $5.00. Build your own case, instructions free; ke good profits selling your friends. Clock works with chimes for old or new cases. Write for full particulars. Clock Co., Nicetown, Penn. TO the man who likes to work with tools, Popular Science Monthly offers the opportunity to purchase lue- rints giving details of the construction of useful articles or the home. The following are a few of the blueprints available: No. 1, Sewing Table, No. 5, Kitchen Cabinet, No. 13, Tea Wagon, No. 15, Workshop Bench, No. 17, Cedar and Mahogany Chest, No. 43, Four Tube Radio Receiver, 44 and 45, Model Pirate Ship, 46 and 47, Spanish Galleon, 48, Model Saliing Yacht. Send 25c for each blueprint that you wish to + 2 Science Monthly, 242 Fourth Avenue, New York, N. MEN! Women! Earn $1 an hour at a Weaving Colonial Rugs, genuine fluff rugs, fancy fabrics, from new and other materials. Home weavers always busy. You learn in 30 minutes. Weguaranteeit. Looms — at reduced prices. Liberal Pay-As-You-Weave term Solve YOUR" more-money problem by writing for FREE Loom Book today. Union oom Works, 482 Factory St., Boonville, N. Y.

Fe 2

0 NE ER SSN

Help Wanted MR. BRUSH SALESMEN—Oldestabiished New York Brush Manufacturers require the services of men in all territories to sell their extensive line of SanitaryTwisted- in Wire Brushes. We pay larger ae than any other Brush House in the country. rite immediately for our proposition. Wire Grip A bone Brush Cor- poration, 15 Mercer Street, New York. EARN $25 weekly, spare ge writing for news- peers, magazines. Experien unnecessary, Details ree. Press Syndicate, 971, St. "Louis, Mo. ONLY 1 sale daily means $135 per month profit. Full or ware time. New $5000 Accident & Sickness Policy, $25. Weekly a aay gage RY, - Tremendous lemand—am: ae poet os ee with State. write que fo’ ~4y Tegebver? ed Underwriters Dept. 701.

uritory and Bide. ak nN.

WANTED—Representatives in every factory in ihe United States. Popular Science Monthly, 250 Fourth Ave., New York. STEAMSHIP positions—Europe. Orient. Good Ee. Experience unnecessary. — of positions free. Ox 122-Z. Mount Vernon, N. SILVERING Mirrors, French > 5 Easily learned; immense profits. Plans Mirror Works, Excelsior Springs, Mo BE a Detective. Earn Big Money. Send $1 for year’s

FORMULAS: The Best Chemical Science can de- vise—Guaranteed Reliable Processes in all lines. Stamp Brings Big Bunch of Valuable Literature, ay atone om | Lists. Don't buy till you receive this. Chemical Analysis, Charges reasonable. Dr. Liscomb Miller, Chemist, Tampa, Florida. FORMULA by Richards means the best. Your chemi- a 2 —— and workirg wi furnished $5.00. te me. W. Stedman Richards, Consulting Chemist, Box 2402. Boston, Mass.

Languages

WORLD-ROMIC System, Masterkey 5,000 languages. Primers $1.98. Chinese, French, Spani: sh—Languages, 8 West 40th, New York.

Letter Specialists

ywhere on receipt of remittance with order a Films. 1000-foot reels, $2.50 each; Stipa pendent Films, 303 West Commerce, San Antonio, Texas, -

Motors, Engines and Machinery

MOTORS—New GE 110 or 220 wi y Ay Phase, % HP $11.90, 4% HP $28.53, $3 Check or Money O We it Bd < r- where. Motor Specialties Co., Crafton, Penna. roe ). anys

Music and Musical Instruments

SAXOPHONISTS — Clarinetists — Cornetists — Trombonists—get “Free Pointers.” Virtuoso Musie School, 36, Buffalo, N. Y. PRESERVO Pad Rejuvenator renews saxophone and and clarinet pads, saves repadding, —_- Playing eagy, Postpaid 50c. Non Pressure. Afton, Iowa Office Devices ADDRESSING machines, multigraph, duplicators, folders, check writers, sealers, dictating machines, at about half new cost. Pruitt, 117 N. Market St., Chicago. WANTED—Rrkepresentatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York.

— Optical Goods ARTIFICIAL eyes. Booklet free. Denver Optic, 508 Barclay, Denver, Colorado.

I WRITE letters, folders, booklets, complete followup for manufacturers, mail order dealers. Long experience. _ for details. L. Taylor, 314 Brown Bldg., Rockford,

MR. ADVERTISER: Ask today for a copy of the “Quick-Action Advertising Rate Folder.’’ It contains some really important facts which will prove interesting and valuable to you. It also tells “‘How You Can Use Popular Science Monthy Profitably.’’ You'd like to know wouldn't you? Manager, Classified Advertising, Pop- ular Science Monthly, 250 Fourth Avenue, New York. SALES creating letters written. G. W. Anderson, Post Office Box 1244, Phoenix, Agiz. SOAS ATER” SRE ST SA SA Machine Tools CONCRETE Building Block Machines and Molds. ogg om tag Concrete Manufacturing Co., 5 N. Main, 8, Mo. ace Magic Tricks BE a magician, give shows, earn money. 20c. Oaks Magical Co.,

Catalogue Dept. 5&0, Oshkosh, Wis. BOOKS, Magic, Mysteries, Magic Tricks, Novelties. Catalogue ‘Free. ‘Singer 515, Hancock, Wisconsin. AMAZE and Mystify your friends! New 80-page Book, 500 Tricks, tells how. Postpaid 10c. Lyle Douglas Station A-4, Dallas. Teas. BEAUTIFUL 160 page catalog of Jewelry, Tricks, Puzzles, latest novelties, 10c. American Bazaar, Inc., Dept. 30, 640 Broadway, New York.

Mailing Lists

MAILING Lists of stockholders—Investors—In- dividuals Business firms for every neei. Guaranteed— reliable and individually compilei. Catalogue and in-

membership to Continental Secret Service System, formation on uest. National List Co. e345 Broad Box 81K, Waukegan, II St., Newark, N. MEN, get Forest Ranger job: permanent: $125-$200 MR. ADVERT TSER: Ask today for a copy of the mo. and home furnished; hunt, fish, trap, etc.; experience “ ” aa sory. Wor details W. rite Norton, 224. eMann, Quick-Action Advertising Rate Folder.” It contains Denver, Colo. GIRLS: Earn good money at home. Spare time. Color Christmas cards. We show you how. Send $1 for first supply of 24 cards, envelo to match. Arts and Crafts Company, 3668 So. Michigan, Chicago.

some really important facts which will prove interesting and valuable to you. It also tells “How You Can Use r Science Monthly Profitably.”” You'd like to know, wouldn’t you? Address your inquiry to: Manager, Clas- sified Advertising, Popular Science Monthly, : 250 Fourth Avenue, New York.

MR. ADVERTISER: Ask today for a copy of the “Quick-Action Advertising Rate Folder.” It contains some really important facts which will ag interne and valuable to you. It also tells ‘‘How You Can Pcpular Science Monthly Profitably.’’ You'd like to know, wouldn’t you? Address your inquiry to: Man: Classified Leg ye a Science Monthly, 250 Fourth Ave., New York ‘

Patent Attorneys PATENTS—Time counts in applying for patents. Don’t risk delay in protecting god if eas. Send sketch or model for instructions 7 write for FREE book, “How to Obtain a Patent” and “Record of Invention” form. No charge for information a how to proceed. Communica- tions strictly confidential. Prompt, careful, efficient service. Clarence A. O’Brien, Registered Patent ‘Attorney, Security Bank Building Vw od across street from Patent Office), Washington, D. C. (See page 153) “INVENTOR’S Adviser,” the valuable Patent book with 139 mechanical eg and illustrations, sent free upon request—M. Labiner, Patent Attorney, 3 Park w, New York. PATENTS—Before disclosing an invention the in- ventor should write for our blank form ‘‘Record of Inven- tion.”” This should be signed, witnessed and returned to us together with model or sketch and description of the Invention for Free Inspection and Instructions. Ou hree Books mailed free to inventors. Our illustrated uide Book, “How to Obtain a Patent,” contains instructions regarding patents. Copies of unsolicited letters from manufacturers and others who are constant- ly writing us regarding the purchase or leasing of merito- rious patents sent — request. See advertisement on ae a Victor J vans & Co., 937 Ninth, Washing- on, D. C. PATENTS, trade marks, copyrights. sonal reliable service. Over 30 years’ —e practice. Write for terms. Book free. Address E. G. Siggers, x 1, N. U. Building, Washington, D. C PATENTS. Booklet free. Highest references. Best results. Promptness assured. Watson E. Coleman, Patent Lawyer, 724 9th Street, Washington, D. C. INVENTORS’ Guide free on request; gives valuable information and | tte for all who have original ideas or improvements. rank Lederman, Registered Attorney and Engineer, siaaaaets Bidg., 1714, New York. UNPATENTED Ideas Can Be Sold. I tell you how and help you make the sale. Free particulars (Copy- righted). Write W. T. Greene, 811 Jenifer Building, Washington, D. C.

Prompt, per-

Page 137

ble ow py- PARTIAL LIST of States, Cities and nstitutions in which Graduates of U.of AS. Hold Positions as Finger Print Experts State of Iowa State of Idaho State of Colorado State of Alb bon, Mg soe Mr anyCo.Penitentiary Albany, N.Y. Waterloo, Iowa bd Barre, Pa. LorainCounty,Ohio Ogden, Utah Gainesville, Texas Walla la, Wash. Indiana Reformatory yy gt Ind. . Joseph, Mo. Mingo Junction, Ohio Okmulgee, Okla. Hazelton, Pa. Yakima, Wash. OklahomaCity,Okla. Des Moines, Ia. East ® Globe, Arizona Hamtramck, Mich. London, Ont., Can. Henryetta, Okla. Seattle, Wash. ma. Mo. rumright, Okla. Lima, Ohio Victoria, B. C. $2500 Reward MONEY MAKING OPPORTUNITIES SECTION for the Capture of an Unknown Man! WICE he had entered the St. Clair Mansion. What was he after? Who? What was in danger? Berteau, the famous detective, had warned St. Clair that the mysterious marauder would come again. passage! The creak of an opening door. Is this wounded stranger the mysteriousintruder? Who could tell? Yet Berteau identified the man without hesitation and won the $2500 reward. How did he do it? Easy enough for the Finger Print Expert. He is the specialist, the leader, the cream of detectives. Every day’s paper tells their wonderful exploits in solving mysterious crimes and convicting dangerous criminals. More Trained Men Needed Thedemand for trained men by governments, states, cities, detective agencies, corporations and private Secret Service Reports FREE Just mail the cou ation the bona fide reports made by o. 38 to his chief. Better than fiction! Leads you through every step in the solution of a mysterious murder and a daring pe robbery. Shows how Finger Prints become infallible evidence. nm and we will send = without cost or obli- ret Service Operator Get the big illustrated book on true Finger Print cases now offered free. Also our special offer of a Professional Finger Print Outfit and a Course in t Service Intelligence now being made for a limited time. The coupon brings it all. Mail it now. You ha ing to gain—Nothing to lose. University of Applied Science 1920 Sunnyside Av., Dept. 13-69 Chicago, And now—a noise in the A shot in the dark! A capture! bureaus is becoming greater every day. Here isa real opportunity for YOU. Can youimagine a more fascinating line of work than this? Often life and death depend upon finger print evidence—and big rewards go to the experts. Many experts can earn regularly from $3,000 to $10,000 per year. Learn at Home in Spare Time And now you can learn the secrets of this science at homein your spare time. Any man with common school education and average ability can become a Finger Print Detectivein a surprisingly short time. University of Applied Science 1920 Sunnyside Ave., Dept. 13-69 Chicago, Illinois Gentlemen: Without any obligation whatever, send me the Confidential Reports of rator No. 38—also your big Finger Print Book and Special Offer now open. Name Street Address City and Siate Age.

Page 138

Patent Attorneys MONEY MAKING OPPORTUNITIES SECTION Razors and Blades December, im Salesmen.and Agents Wanted e MILLIONS spent annually for ideas! wanted! Patent yours and profit! Write today for free book—tells how Pg rotect eget how to invent, ideas wanted! How we help a 1, etc. American indus- tries, Inc., 501 Victor ldg., ny eS ay >. C, PATENTS, Trade-Marks, all countries. Ten years’ experience e examining applications in Patent Office. Consultation invited. George Beeler, Patent Attorney, 150 Nassau Street, New York. MONROE E. MILLER, eg Bldg., Washington, D. C., Patent Lawyer, Mechani: lectrical Expert. Book- let and Priority Record Dinan ‘gratis. PATENTS—Send for form ‘Evidence of Conception” to be signed and witnessed. Form, fee schedule, informa- tion free. Lancaster and Allwine, Registered Patent Attorneys in United States and Canada, 232 Ouray Bldg., Washington, D. C. PATENTS Procured: Trade Marks Registered.—A comprehensive, experienced, seremnt service for the pro- tection and = res e. your ideas. Preliminary ladly fu: ed without charge. Booklet of in- formation and form for diselosing idea free on ao Richerd B. Owen, 44 Owen Bidg., Washington, D. C., or 41-Z Park Row, New Yo York. MR. ADVERTISER: A8k today for a copy of the “Quick-Action Advertising Rate Folder.” It contains some really important facts which will prove interesting and valuable to you. It also tells “How You Can Use Popular Science Monthly Profitably.” You'd like to know, wouldn't you? Address your inquiry to: Manage: Classified Advertising, Po Po pular Science’ Monthly, 250 Fourth Avenue, New RICHARD E. Taboseke “Patent Lawyer, —— Loan & Trust Bldg., Washington, D. C. ooklet PATENT Book Free. Charles. W. ime Patent Attorney, Lynn, Mass. GET your own patents. Instruction $1. _s Patents Pay, $1. Cooper Cutting, Campbell, Calif INVENTORS who, derive largest profits know and heed certain — but_ vital — ‘pefore ves, tose for a “Pate = FS wg sent free. Write ahaa and Lacey, G48 ashing- C., Established 1869. Hundreds now MIDGET Safety Razor, with dozen blades. Wallace Kutz, 132 Chambers, Phillipsburg, N. J 3SAFETY Razor Blades—2 Doz. $1.00, postpaid. Double edged. For Gillette and similar razors. Guaran- teed good as any on market. Owl Supply Co., 3509 Ohio, St. Louis, Mo. Real Estate—Orchards—Farm Lands PECAN-Orange-Fig Groves ‘‘On the Gulf’? Monthly payments. Guaranteed care. Big, quick returns. Sub- urban Orchards, Dept. “sn Biloxi, Miss. LAND free if planted to bananas. Bananas bear a full crop the second year. $5.00 monthly will plant five acres, which should pay $1,500 profit annually. Reliable Com- panies will c itivate and market your bananas for Bananas ripen every day and you get your check every 90 days. For particulars address National Development Co., Eepire Building, Block 134, Pittsburgh, Pa. Salesmen and Agents Wanted AGENTS—Clever invention! aay ee makes every pen a fountain pen. Fast office seller, big profit, demand increasing everywhere. Exclusive territory offered. Sample free. H. Marui Company,Tribune Bldg., New York. INSTANT W eld—Repairs large punctures without cement or heat. Lenn’s profit one day $56. Write quick. Free sample. Territory going fast. Tourist’s Pride Mfg. Co., Desk R, Minneanolis, Minnesota. GEr our free sample case, toilet articles, perfumes and | Wonderfully profitable. La Derma Co. ke . St. Louis, Missouri. AGENTS. $60—$200 a rox. Genuine for store windows easily appl: offer to general agents. Clark, Chicago, TAKE orders for coffee, sugar, flour, meats, canned goods, staple groceries, also paints, radio ag tires, auto and tractor oils. No capital or bond - 2 ired.’ We deliver and collect. tmanent business. g pay. Write at once. Hitchcock-Hill Co., Dept. 81, } Hg ” cents. old letters ied. Free samples. Liberal Btaillic Letter Co. 434-A. N. Patents for Sale INVENTORS: a wd — service for presenting your invention or ee Auam Fisher Mfg. Co:, 18324 Snright, St. Louis, M OUTRIGHT or royalty, oe Fighting ae No fire station is ween thout this remarkable ex- tinguisher. Jas. C, itt, penalty La Patents Wanted PATENTS wanted:—We buy and sell practical pat- ents. Big opportunity, undeveloped field. Describe briefly. M. Okamura, Box 1290, Honolulu, Hawaii. Photographs and Supplies HAVE you a camera? Write for free sample of our big magazine, showing how to make better pictures and earn money. American Photography, 117 Camera House, Boston, 17, Massachusetts. ESTABLISH yourself at home, as a Photographic 5 a week while learni: professional camera furnished free; write ull information. International Studios, Dept. 1743, 3601 “Michigan Ave., Chicago. WANTED—Representatives in every factory. Popu- lar Science Monthly, 250 Fourth Ave., New York. = =—3 Printing and Engraving BANKRUPT and Rummage Sales. Make $50.00 daily. We start you, furnishing everything. Distributors Dept. 34, 609 Division, Chicago. $10 DAILY silvering mirrors, plating and refinishing lamps, reflectors, autos, beds, chandeliers by new method. Outfits furnished. Write’ Gunmetal Co., Ave. B, Decatur, Illinois. 35% COMMISSION. - Sell Cards and boxes. Philadelphia. TO SELL Ray-O-Lite cigar and gas lighterso mr earnings. Sample 50c. Rapid Mfg. Co., 7 oes Brow way, New York. ANY salesmen can sell them! Merchants everyahne use punchboards. Someone sells them, why everyhen Collect big commissions daily. Newest, largest elaborar, catalog sent upon request. Lincoln Sales Co., 958, Clin ton, Chicago, Dept. G. $100-$200 WEEKLY. Retailers live wi, soe $40 weekly guaranteed against com. toe hae Guarantee dealers turnover or money to investigate. Appleton Specialty Co., “Cedar Pw Iowa. AGENTS—Sell attractively displayed fast selling § candy specialties to stores—Big pata rae selusie rights—Salesmanager, Box 971, Richmond, V FORDS—No boiling, no freezing, big gas sauw saving. Airlock absolutely does it. Sells like imachine Suns fire. Airlock Products, Burnett, California STARTLING selling plan! $1.25 5 premium free to every y customer on $2.00 sale of 8 ounce Vanilla, 6 ounce Sham. poo and 4 ounce Lemon Lotion. Details and Samples free, C. I. Togstad, Dept. 19T, 29 S. Clinton, Chicago, Tl, GREAT neckwear line now free! Features’ fines; quality neckwear at factory prices. Collect big com. missions daily. Write for FREE tie offer and outfit. Nawco Neckwear, Desk 12-C. Covington, Ky, McDONALD Polishing Cloth. Cleans gold, Silver, nickel. Sample 15c _- Daniel J. McDonald, j 18 Agawam St., Lowell, Mas ADVERTISER: ie today for a copy of the “Quick-Aetlon Advertising Rate Folder.” It containg some really important facts which will prove interesting and valuable to you. It also tells ““How You : Ue Popular Science Monthly agg, 8 ** You'd like to know wouldn’t you? Manager, Classified ‘Advertiong. 2 gal Science Monthly, 56 Fourth Avenue, New 0) Folder f “Wollegena older free. olfeprint, Lawn AGENTS—Steady income. . Large manufacturer of handkerchiefs and dress goods, etc., wishes representg. tive in each locality. Factory to consumer. Big profits, honest goods. Credit given. Send for particulars. Free port Mfg. Co., 24 Main St., Brooklyn, N. Y. “AMAZING New Cleaner” cleans ever rything. Sells Sells 25c. Profit 17c.. Sample Free. Bestever Products Co,, 1943-P, Irving Park, Chicago. AUTO Emblems. Any Lodge. Write. Distributors, Dept. M, Ashland, Ohio. North Central AGENTS—Best seller; Jem Rubber Repair for tires and tubes; supersedes vulcanization at a saving of over 800 per cent; put it on cold, it vulcanizes itself in two tube; sells to every auto owner and accessory dealer. For particulars how to make big money and free sample, ad- dress Amazon Rubber Co., 504 Amazon Building, Phila- delphia, Pennsylvania. BIG money and fast_sales. Every owner buys gold initials for his auto. You charge $1.50; make $1.35. Ten orders daily easy. Write for particulars and free samples. American Monogram Co., Dept. 47, East Orange, New Jersey. AGENTS—Stamping names on Pocket Key Pro- tectors; sample check with your name and address, 25c. Sromping Oust, Emblem Checks, Check Fobs, Name Plat art Mtg. Co., Desk 2—305 Degraw St., Breen m, ¥. ADVERTISER: Ask today for a copy of the “guick-Actlob Advertising Rate Folder.” It tells “How You Can Use Popular Science Monthly Profitably.’’ You’ d like to know, wouldn’t you? Manager, Classified Advertising, Popular Science Monthly, 250 Fourth Avenue, New York. A BUSINESS of your own—Making Sparkling Glass Name and Number Plates, Checkerboards, Signs. Big Book and Sample free. EF. Palmer, 513, Wooster, Ohio. BETTER Printing for Less Money. Write us about our printing needs, and you will save money. Ernest Fantus Company, 525 South Dearborn Street, Chicago. SELL by mail! Big Profits! Books, Formulas. Novelties, Bargains. oe Free! Elfco, 523 South Dearborn Street, Chicag COMMERCIAL ee a and Factory forms. Ask for prices—good work. Illini Press, 833 First St., La Salle, Ill. MR. ADVERTISER: Ask today for a copy of the “Quick-Action Advertising Rate Folder.” It contains some really important facts which will prove interesting and v It also tells ‘“‘How You Can Use You'd like to know wouldn't you? Manager, Classified Advertising, Popular Science Monthly, 250 Fourth Ave., New York. THOUSAND Hammermill letterheads, four dollars. Multigraphing. Jno. Mavray, Monmouth, Illinois. AGENTS—Make a i an hour. Sell Mendets, a eee patch for instantly mending leaks in all utensils. ample package free. Collette Mfg. Co., Dept. 467, Amsterdam, N. Y. EARN $10 daily silvering mirrors, orang J and re- finishing metal ware, headlights, chandeliers, bedsteads. Outfits furnished. F. Decie Laboratories, 1133 Broad- way, New York. MILLIONS stolen. Remarkable new $5.00 Check Protector stops forgery. Inks, protects two colors. Sensational sa “. i. Write. Safety Devices Corp., Grand Rapids, M STATIONERY Embossers make Practical Christmas Gare. Write to-day. Midwest, Box 47, Springfield, inois. 5000—20 LB. Hammermill Bond letterheads $12.75; 10,000—$22.75; 5000—6% white wove envelopes $9.00. Imitation ty, riter letters our specialty. a for prices. The Courier Company, Zanesville, Ohio FIVE hundred gummed stickers printed your name and address 25c. Premier Service, Antes Fort, Penna. 500 LETTER heads, 500 envelopes, $5.00. Jean McLane, 1215 Russell Ave., Bethlehem, Pa. FORMULAS oe making ucts. Investment Small. Machinery Needed to 1200% profit! Stam Brings Interesting Descriptive Literature for Fly Killing Spray, Delicious Summer Hair Marcell Liquid, "No-Water Hand Soap, Li ghtning Battery Charg- ing Liquid, Mendit, Fabric ’ Patching Liquid; Amazon Tire Repair, Wai shing Com junds; Compolith Wood- stone, Wonder Gloss; Wizard Polish; Pure Food; Toilet, edical, Household Specialties, All ‘lines. State what interests most. Miller, Chemist, 1706 Jettony, Tam- pa, Florida. your = guaranteed if Deed. 200 SHEETS, 100 Envelopes Printed, Name, Address linen stationery "$1.00 (west of Rockies $1.10). Hi-Type Stationery Co., 153 Lafayette St., New Haven, Conn. Printing Outfits and Supplies PRINT rds, stati circulars, a etc. Complete outfits $8.85; Job Presses $11. $29: — $149. Print for others, = profit. ‘All easy, rules rite for catalog oN type, paper, etc. Kelsey cence F-3, Meriden, Conn Radio and a Owner,”’ “3 pend 10c to-day to Universal Test Equip- ment Co., Oakley Ave., Chicago, Ill. Sold at all news aE ng A: the City of Chicago. RADIO Boosters — BCL’s Wear our Radio Pin on your coat. Everyone admires it. $1.00. S. K. W., 10 festwood Drive, San Francisco, California. AGENTS, both sexes, we manufacture and control new household article. Fast seller. Big profits. Exclusive seertbery. Write now, Connolly, 123 Liberty St., New or MR. ADVERTISER: Ask today for a copy of the “Quick-Action Advertising Rate Folder.” It contains some really important facts which will prove interesting and valua to 07m. It also tells ““How You Can Use Popular Monthly Profitably.” You'd like to know, wouldn’t you? Address your inquiry to: Manager, Classified Advertising, Popular Science Monthly, 250 Fourth Ave., New York. POLMET Polishing Cloth cleans all metal. fast at 25c. Sample free. F. C. Gale, St., Boston. AGENTS—new plan, makes it easy to earn $50.00 to $100.00 weekly, selling shirts direct to wearer. No capital or experience n present a real manufac- turer. Write now for free samples. Madison Company, 566 Broadway, New York. AGENTS! Big_ money monogramming by transfer method. Catalog showing over 50 styles and particulars free. Motorists’ Accessories Co., Mansfield, Ohio. “GOLD initials easily applied on Automobiles. Big- gest moneymaker today. Cost. 5c, you get $1.50. Ni experience needed. Free sam ies.“ Ralco” “‘Mondgrams, Sells 15 Edinboro 1043G Washington, Boston, Mass.” AGENTS—Sell Scientific Device for Fords. Prevents overheating. .Guaranteed to cool motor, better than — coe together with regular fan. Best seller of the rite for particulars. Debothezat Impeller Co. “1922 Park Ave., New York. SELL new and used clothing to general pine 9 and Tailors. Numerous other new _ articles. en a Dept. P, 2549 So. Halsted, Chicago. E $100 weekly in spare time. Sell what the public poh ae Be, distance radio receiving sets. Two sales weekly pays $100 profit. No big-investment, no canvassing. Sharpe of Colorado made $955 in one month, Representatives wanted at once. This plan is sweeping the country—write today before your county is gone. Ozarka, Inc., 481 N. La Salle, Ave. L, Chicago. NEW Ford shock absorbers retail at $3.00—100% rofit. Also other good money makers—5004 profits, ree sample of windshield coatings. Safe-Vu Co., Dept. A., St. Louis. ‘SALESMEN We Pay You Well. Hardensburg’s famous line of leather goods, diaries, calendars and other advertising specialties. Product ‘of 48 years’ experience. Easy’ sales, satisfied customers, big com- missions. Serious offer for hustling salesmen. H. B. Hardenburg & Co., Inc., 423 Elizabeth Ave., Linden, N. J, SELL Apronalls. Season’s Biggest Hit. Easy to earn $15 in single afternoon. Everybody buys. No competi- tion. Selling outfit furnished. Write today for special agents offer. Apronall Co., Chamberlain, S. D. SALESMEN—Tremendous Repeater. Used by Mil- lions. $20 profit on ten, $3.50 sales. Merchants repeat orders build you permanent business. Auto Bonus. Territory. Full or side line. Hustlers wanted only. Elcor Products. Dept. M-10, Washington, D.C, MR. ADVERTISER: Ask today for a copy of the “Quick-Action Advertising Rate Folder.” It contains some really important facts which will prove interesting and valuable to you. It also tells ‘‘How You Can Use Popular Science Monthly Profitably.” You'd like to know, wouldn’t you? Address your inquiry to: Manager, Classified Advertising, Popular Science Monthly, 250 Fourth Avenue, New York: MANUFACTURER Lambs Wool, Polishers, Dusters. Newhall, 358 Broad, Lynn, Mass. STOP Wasting Time. Send name, address. “Nuff said.” German G. Martin, Box 124 East Ave. Sta., Rochester, N. Y. AGENTS wanted to distribute samples, big money, new method, write quick. P. S. Vann, Box 3, Sta. D, New York. AGENTS: Make $500.00 before Xmas. Pay daily. No investment. Rhinestone initial Buckles and novel- ties. Big Xmas and all year sellers. Exclusive territory. Chaton Novelty Co., 606 Blue Island, Chicago. AGENTS wanted. 20 shaves $1.00. New Liquid eliminates razor. Yours for the price. Hylon Labora- tories, 2704 North Halsted St., Chicago. WANTED—Representatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York. PROFITS 100% selling quality guaranteed perfumes and toilet preparations that produce permanent repeat sales. Liberal free goods. famee Perfume Co., 3330 Carroll Ave., Chicago, Ill., Dept. AGENTS for well known sutemebile polish—full or part time basis. Experience not necessary. Ambitious man, willing to work, can make real money on bbe. proposition. Big commission allowed. A real op tunity for the right man. Barthel Laboratories, Webster Ave., N. Y. WONDERFUL Pocket .Adding Machine and Magic Writing Pad. Retails $3.00. To Agents 50c in quan- tities. «particulars Free. Typewriter Supply i 541 Hersch Bide., Pittsburgh, Pa. SALESMEN to sell all wool, hand tailored, made to measure, suits and overcoats $33.50. Commission $3.50, large line 6x9 sample swatches, easy to sell. Write for pa Hetm Tailoring Company, Department 7, 616 Baltimore Street, Baltimore, Md.

Page 139

MONEY MAKING OPPORTUNITIES SECTION sell this ee tire INSURED-i2:.03¢ Make up to $100 Weekly by Taking an Agency for Hvdro ‘Insured’ Tires—Sold Only Thru Authorized Salesmen-Agents o] Babel 922i] Eel EE] 5 If ycu would break away from the monotonous routine of working long hours for asmall salary—if you would want a snug bank account—if you want full or spare time occupation in dignified and fascinating work—BE MY PARTNER! Become an agent for HYDRO ‘Insured’ TIRES and withmy assistance you will quickly establish a profitable tire business right in your own community. Every car owner wants Hydro Tires because they have no competition in price —no rival in quality—no imitation in appearance —and no equal in the insured pro- tection to the user. The User’s FIRST and ONLY Cost | less than Dealer’s Prices on No capital is required! The Hydro Plan is based on the fact that in every community there are worthy men who could easily become successful if they had the proper incentive. Many of these men are harder workers, better salesmen, and capable of mak- ing more money for themselves than the dealer who waits for business to come to his store. Perhaps YOU are the man we are looking for! If so, here is the chance of a lifetime to ~ earn real money, because you sell a necessity that has one of the greatest markets in the world. Your prospects are limited only by the number of cars in your territory. Investigate! SEND other Uninsured Brands Ours is the only tire fact- ory in America selling its product only through authorized Salesmen- Agents. Eliminating the profits of jobbers, brokers and dealers enables us to offer car owners, real, outstanding Tire Values which mean quick sales Testers “The Most Beautiful Tire in America” HYDRO TIRES —un- surpassed in quality and outstanding in perform- ance, are definitely insur- ed forONE FULL YEAR against everything except theft! Each user is fur- nished with a Tire Insur- ance Policy that assures him a year’s tire service regardless of wear or mile- age. This is the sort of protection every car own- er wants and Hydro is the first to offer it. It is the user's Guarantee of Service. Be the first in your community to sell tires that are completely INSURED for one year Act Now! Before Your Territory is Allotted The man who succeeds and makes money is he who grasps an opportunity quickly. Hydro Agents are accepted on the exclusive territory basis. I want you to represent mein your ter- ritory , where there are thousands of dollars in profits waiting for some live hustler. I'll give you every cooperation. Just send us the coupon below and you can get started at once. QQ a President. for Your SELLING KIT now! This valuable KIT, complete for making demonstrations and easy sales, is supplied to Hydro Agents under our Agency plan. THE BUSINESS OPPORTUNITY OF A LIFETIME! Want to make extra money evenings and during spare time? Want to establish yourself in an enjoyable, profitable business of your own? Send now forcomplete details of the Hydro Exclu- sive Agency plan! Bea Partner in this $1,500,000. company. Ambitious men are now making money by selling HYDRO TIRES. You can too! sais NOW! Coupon HY DRO-UNITED TIRE CORPORATION, Pottstown, Pa. Tell me how I can secure the Hydro Agency for my terri- tory, and make up to $100 per week as your representative. - This does not obligate me in any way. PSM-12-26 Name Address “ HYDRO-UNITED TIRE CORP... POTTSTOWN,PA.__

Page 140

142

10 DAYS’ TRIAL SEND NO MONEY NO NEED FOR A NEW PHONOGRAPH —The w PHONIC Reproducer makes an up-to-the-minute Phonograph out of your old one 85 con from Factory

“only Gives the New Tone and Volume of Latest New Phonographs Now at last you can say goodbye to the squeaky, nasal, rasping, metallic tone of your phonograph. Now you can have the beautiful, tend full-round- ed tone of the expensive new machines which are startling the world. Yet you need not buy a new phonogra _ if you have an old one. The reproducer f the HEART of any phonograph—and the New PHONIC reproducer makes your old phonograph like an entirely new one. Based on the new PHON Nic principle. Makes you think the orchestra or artist is in the same room. Never Before Such Tone Tones never before heard are clearly distinguished when the new PHONIC reproducer is used. Test it on an old record. Hear the difference yourself. Listen to the deep low notes and the delicate high notes. Hear how plainly and clearly the voice sounds. Note the natural tone of the violin and the piano, and the absence of “tinny” music. You will be amazed. Volume Without Distortion The new PHONIC reproducer is ideal for dancing or for home entertainments. Its volume is almost double that of theo! ry reproducer. Yet there is no distortion of sound. The new principle enables you to use even the very loudest tone needies without the ear-splitting effects of old reproducers. The new PHONIC is always mellow and natural. 10 Days’ Trial—Send No Money You cannot realize how wonderful the New PHONIC is until you hear it. That is why we want to send it to you on 10 days’ trial. ~ bg soeaty now— just the coupon. Pay the postman only oa a few pennies postage when the New PHONIC. arrives. Then if you are not delighted, send it back within 10 days and your money will be refunded. The low price is made sible by ine direct with phonograph owners. If so ice would be at least $7.50. Our price em 4 $3.85. - Bena dealt with us by mail. You take n now for 10 days’ trial. BE SURE TO STATE NAME OF PHONOGRAPH YOU OWN. NATIONAL MUSIC LOVERS, fue. Dept. 812 327 West 36th Street, New Yor' Please send me a New vathiee reproducer for 28 OO ee I will pay the postman $3.85 (give name of Phonograph) plus few cents postage. If I am not satisfied after trial, I will return your reproducer within 10 days and you guarantee to refund my money.

Salesmen and Agents Wanted MONEY MAKING OPPORTUNITIES SECTION

December, 1%

Salesmen and Agents Wanted

BUY our absolute necessity 2c— sells 25c. We undersell all. Seven samples 30c. Catalog tree. Mills Sales Co., 13 E. 16 St., New York. EARN $45 to $85 extra a week. Selling beautiful Shirts. Commission in advance. We deliver and collect. Write quick. Fashion Wear Shirts, Dept. S-632, Cin- cinnati, Ohio. MAKE—SELL Your Own Goods. experts. Manufacturing Processes. Trade-Secrets. All kinds. All lines. Catalog, circulars free. C. Thaxly Co., Washington, D. C

Formulas by

MOST wonderful razor blade stropper-ey Sells on sight to every man. Agents make ama profits. Full or part time. No experience Outfit includes gold-plated blade holder, SPecially pared New Shell strop and beautiful ’ Keratol! ot Retails for $1.50. High-grade Gillette safety ragg¢™™ blade free with each outfit. Greatest money opportunity ever offered. Write for information chart showing how you can make $75 to $200 q Gripsit Corporation, Dept. AJ-1, 405 Broadway, ct bridge, Mass. ‘am.

AGENTS—$11.80 Daily in advance (Sworn Proof) In- troducing New Insured Hosiery. Guaranteed one year. No —_ or experience required. Your pay daily, Monthly bonus besides. Spare time pays you big. We supply samples. Silk hose for your own use Free. — Hosiery Company, Card 15212, Cincinnati, 0. AGENTS—Big Seller—$20 Daily Easy selling Taylor Caps—made-to-measure—every man buys—some want 2 or 3 caps. Samples Free and-Cap Free to agents. Write-quick for fast money making proposition. Taylor Cap Manufacturers, Dept. 0-5, Cincinnati, Ohio. $14.50 DAILY Easy—Pay in Advance, Introducing Chieftain Guaranteed Shirts 3 for $4.95. No experience or capital needed. Just write orders. We deliver and collect. Full working outfit Free. Cincinnati Shirt Company, Secy. 16016, Cincinnati, Ohio. FIRE Salvage Rummage Sales. $50.00 Daily. start you_furnishing —— Jobbers Desk Mis, 1608 So. Halsted, Chicag AGENTS $72 Week. eee new tool chest, 8 fooTs in

= Schools MAKE $75 to $250 weekly; Motion Picture, Portman and Commercial Photography. Camera Free—iit Special offer, write New York — of Photography Dept. 5A 10 W. 33D St., New York. y

Shop Equipment DEALERS—Buy Battery Shop Equipment ay Supplies at Wholesale. Battery Charger $5000 oad Barrs, Columbus, Ohio.

Stammering

ST-TUT-T-T-TERING and stammering cured g home. Instructive booklet free. Walter McDonnell, 34 Arcade, 1126 Granville Avenue, Chicago, Ll.

one. Fine leather case. Fits hip pocket. enormous. Write quick. Novelty Cutlery Oo Chest 232, Canton, Ohio. MAGIC Moving Window Salesman. Its real change- able letter system has actually boosted users’ sales 200% to 400%. None but dead dealers indifferent. If you can spot a winner, get the facts and begin pocketing $100 weekly. Display Products Company, P. O. Box H5123, Gateway Station, Kansas City, Mo. DISCOVERED! Diamond’s Rival—Rajah Gems astound Jewelry world and defy detection. Set in artistic Sterling Silver mountings, copies of highest priced platinum designs. Sell like wildfire at popular prices. Salesmen and Agents unique selling plan means enormous profits for you. Write ey for details. Rajah Company, Dept. Z-12, Salisbury, N. C. AGENTS—Biggest money makers ever offered. Sell offices, homes Bestufone, which makes both hands free while telephoning; Midget Collapsible Garment Hangers. Wonderful Holiday Sellers and Everin Key- purse to hold change and - H. Kalina Company, 1308 Avenue N, Brooklyn, N. AGENTS—Our gold-eyed needle cases are wonderful sellers; immense profits; $50 to $300 weekly; proof and particulars free; sample outfit 15c. Paty Needle Co., Somerville, Mass. SELL men’s neckwear; wonderful proposition. 318-G Broadway, New York SALESMEN, go into the office accessory and supply business. We furnish complete lineup. Build a perma- nent business that pays big money. Write for particu- lars. Davis Company, 10 Tremont, Boston, Mass. AGENT makes $57 a day driving nails in tire! Amaz- ing discovery heals all Rg Ey tire was punctured ag) times without a d for free Sample Offer. O. S. Nelson, T-3189 Logan Bidg., Mitchell, S. Dak. FREE Adding Machine to ‘“Live-Wires’’ accepting our Dollar-a-Minute Agency. Improved 2-lb. Calculator. Adds, Subtracts, Multiplies, Divides. Work equals $300 machines. Retails $15.00. Big demand; large profits. Write quick for protected territory. Lightning Calcu- lator Co., Dept. P, Grand Rapids, Mich. AGENTS wanted to advertise our goods and distrib- ute free samples to consumers; 90c an hour; write for full particulars. American Products Co., 6327 Monmouth, Cincinnati, Ohio. MIRRORS resilvered at home. Costs less 5 cents per square fgot; you charge 75 cents. Immense profits, plating auto parts, reflectors, tableware, stoves. le- finishing metalware, etc. Outfits furnished. Write for information. Sprinkle, Plater, 96, Marion, Indiana. O DULL times selling food. People must eat. Federal distributors make big money; $3,000 yearly and up. No capital or experience needed; guaranteed sales; unsold goods may be returned. We furnish you with sample case, license and free eee 34 customers! Sure repeat orders. Exclusive territ Ask now! Federal Pure Food Co., AA2307 ‘Areher,” Cc hicago. SELL Radium Water Generators. Entirely new fast seller, repeat orders sure. Permanent income. Ask Why ~a- Radium Refinery, 2209 Broadway, Oakland, Salif. SURE Seller to every merchant—no gamble—big profits—steady repeater—free sample and exclusive territory. Embossed Show Card Co., 9462 Euclid, Cleveland, Ohio. AMAZING large cash commissions introducing beautiful $3.95 and $4.95 Fit-to-Measure guaranteed shoes. Actual samples furnished. Write for your terri- =<. Style Arch Shoe Co., Dept. 106-M, Cincinnati, 0. AMAZING new invention, duplicates anything type- written, handwritten, drawn, ruled. ee. easily operated Salesmen coining money. Write free sample offer today! Stenograph, 1271 California, San Francisco. REAL Selling Sensation! Tremendous earnings whole or part time! Patented Hot Water Bottle Combination. Invention needed everywhere. Big commissions. Extra bo We deliver. "Write C1015 Lobl Corp., Middle- boro, Mass. WE PAY $48 a week, furnish auto and expenses to introduce our Soap and Washing Powder. Buss-Beach Company, Dept. A48, Chippewa Falls, Wisc. MERCHANTS now buying gift advertising. Sell red bird fiyer—kitchen tongs—auto smoker set—novelty calendars, etc.. Good sideline, Newton Mfg. Co., Ad- vertising Devt. Newton, Iowa. AUTO Radiator Shutter just out. $20.00 daily easy. Biz winter seller. Retails $1.50. Jones, 802 N. Clark, Chicago. SELLING like blazes! Eleven piece toilet goods assortment at $2. aay with two piece carving set FREE to your customers, 100% profit. Davis Products Co., Dent. 57, 1321 Carroll, Chicago. WANTED—Representatives in every United States. Ave., New York.

Astor,

factory in the Popular Science Monthly, 250 Fourth

Stamps and Coins STAMPS, 100. All diiterent, 3 cents. Lists tree, P. S. Quaker Stamp Co., Toledo, Ohio STAMPS Free—Ask for money-savin appr John K. Borresen, Cedar Falls, low S spree, STAMP Collectors—Puillips Cony bulletia (tus tratei) offers over 2000 special bargains, sets ete. each issue. Free. Phillips, box 1012, atin Conn. SfAMPS, 105 China, etc., 2c. Album (500 illustrations) 3e. Bullard, Station AA, Boston. OLD coins, large Fall selling catalogue of coins for sale free. Catalogue quoting prices paid for coins, ten cents. William Hesslein, 101B Tremont Street, Boston, Mass. FREt! 12 scarce Azerbaijan to approval applicants. Mammoth Illustrated Price List 2c. Pennsylvania Stamp Co., Greensburg, Pa. CALIFURNIA gold $% size, 27c.; $4 size, 53¢. White cent and catalogue, 10c. Norman Schultz, Box 746, Salt Lake City, Utah. EXCHANGE stamps and coins. bership. Trial menbership 25c. 5 Mixed stamps 50¢ (Catalogs $75.00). Rabb, B2256 Maypole. Chicago, BIG Packet Catalogue Une Dollar with One Hundred Twenty Page Precancel Catalogue to Approval Appli- cants. Send Ten Cents for Mailing. Ye Olde Hobbie Shoppe, Port Huron, Mich. STAMP packet 2c to Approval Applicants. Teeple, Decatur, Indiana. NEWFOUNDLAND stamps on approval. None bet- ter—none yg vol Send 10c for he pecial Catalogue— every stamp illustrated. Try these—38 all different (Cat $5) for $1. Rev. Butler, St. Georges, Newfoundland. $10.00 FOR 25c. A choice assortment of 500 all dif- ferent stamps guaranteed to catalogue over $10.00, offered to approval applicants for only 25c. Edgewood Stamp Co., Dept. S., Milford, Conn. UNITED STATES and Foreign Coins. Alexis Mengelle, Colorado Springs, Colorado. CURIOSITY and catalogue—10c. Dime Information Bureau, Colorado Springs, Colorado. 500 DIFFERENT 28c, 1000-85c, 2000-$2.95, None better. Refund guarantee. R. Benno, Glen Ellyn, Ill. 40 OLD coins all different $1.00, 100 different oo $3.00. Monroe Half-Dollar Uncirculated, $1.00 Denney, Box 315, Dallas, Texas. Telegraphy TELEGRAPHY—Both Morse and Wireless—ta thoroughly and quickly. Tremendous demand. salaries. Wonderful opportunities. Expenses low: chance to earn part. School established fifty years, Catalog free. Dodge’s Institute, H374 Hart Ave., Val- paraiso, Ind.

Worldwide Men. 000

Harvey

Typewriters and Supplies TYPEWRITERS:

all makes; lowest prices; 5 year guarantee; send for illustrated catalogue. sm l'ypewriter Co., 217 West 125 Street. New York, “RENT a typewriter.” oy 4 make. If you pay its price in rent, we give machine free. Catalog free. Pgh. Typewriter Supply. Suite 343, 339 Fifth Ave., Pitts burgh, Pa.

Wanted DETECTIVES needed omens. Experience un- necessary. Particulars free. Write, George Wagner, former Government Detective, 1968P Broadway, N. Y. WANTED samples of novelties, new household ar- ticles and inventions, cheap. Write Checkley Novelty Co., 396 Broadway, New York. WANTED—Representatives in every factory in the United States. Popular Science Monthly, 250 Fourth Ave., New York. ARE ory old at forty! See our advertisement on page 165 of this issue. The Electro Thermal Company, 4 Main Street, Steubenville, Chio. Watches WATCHES—All well-known makes at practically

pecet ss] gur squ cal ‘ —— ts 5 o.oo et oe Ee ae ee SS

wholesale prices. Guaranteed new movements; latest models, $1.00 up. Free examination. Write for price on watch desired. No obligation. Progressive Supply Co., 2025-A, Fifth Ave., New York,

Page 141

a 2 Py SES ERE: Ie za] I ee H Ez] I sel TH nee ! ~~ @le “Swe F ~~ ae SF te ys *

December,

<< ] “It’s Brains Against Brains —Fighting Gorillas!”’ (Continued from page 133) gun boy. But in the middle of the field squatted a squirming sack containing Bula Matadi, the largest gorilla ever caught, alive and unharmed. “Bula Matadi, however, did not live to reach the coast. Five of the eight gorillas [captured on my two collecting trips died from various causes. Bula Matadi was stung to death by a troop of marching ants which visited his cage one night, as the camp slept. “7\N MY first gorilla expedition, in 1922, all but one of the captives died on the long march through British East Africa to the Indian ocean. That one I gave to the Antwerp Zoo, where it died a year later. On both trips I entered Africa at the mouth of the Congo and came out clear across the continent on the east coast. The last time I had two gorillas alive when I reached the coast, one for the Antwerp Zoo and one for myself. Again the one I left in Belgium died, so that Miss Congo is the only sur- vivor of the eight. She is a wonderful animal, almost human. You ought to go over to my brother’s country place, at South Jacksonville, and see her.” I did. I spent half a day visiting the only living captive gorilla in the world, and marveling at her likeness to a human being. What struck me as most human- like were the shape of her skull, her use of the facial muscles of expression, which are hardly developed at all in the other apes and only partly in many of the dark- skinned races of man, the perfection of her ears, precisely like human ears—the gorilla is the only animal besides man which has ear lobes—and the perfect human type of her finger nails. Except for her inability: to oppose her thumbs to her fingers, her hands are like those of a human, and she uses them as deftly as many human beings use theirs. HERE is no doubt in my mind, after watching Miss Congo’s manifesta- of human beings. That she can think and reason intelligently to a conclusion, in- stead of acting solely from instinct and imitation as in the case of every other beast, is also the verdict of Dr. Robert M. Yerkes, the distinguished psychologist and editor of the Journal of Comparative Psychology, who had just completed a six weeks’ test of the young gorilla’s mental powers when I visited her. One of Dr. Yerkes’ tests was particu- larly conclusive. An orange, of which the gorilla is especially fond, was hung at a point where, in order to reach it, she would need a stepladder or its equivalent. Three grocery boxes were scattered about the yard, within her reach as she roamed at the end of the long chain with which she is kept fastened to a huge live-oak. (Yale locks are used, incidentally, since Miss Congo learned how to manipulate the common snaffles first used and began to roam around the banks of the St. Johns River.) She surveyed the (Continued on page 144) 1926 MONEY MAKING OPPORTUNITIES SECTION 143 tions of intelligence, that she possesses a | quality of intellect comparable with that

Perhaps this is the opportunity you have been waiting for. Columbia University now Offers to serve men and women who must obtain their collegiate instruction, either entirely or in part, in their homes. olumbia University Home Study Courses You need no longer deny yourself the advantages of college education just because residence study is impossible. At your own convenience, in your spare time at home, you may now take up the study of the subjects you feel you need to acquire a wider culture or greater business or professional effec- tiveness, for Columbia University’s educational work has been extended to those who find it necessary, or preferable, to study at home. These courses are just what their name indicates—Columbia University courses are carefully and scientifically adapted fot the use of those who, through preference or necessity, plan to study at home. Conducted by Members of The University Teaching Staff The courses are conducted by members of the Uni- versity teaching staff who give to each home student, by mail, attention that is just as personal and complete as that given to the student on the campus, adjusting the material to the individual needs of each student, correcting his papers, offering detailed comment and special help throughout the course. While the University does not contend that home study is as desirable for certain pur- poses as classroom work, it recognizes that the student who can not easily adapt himself to the mechanical pre-

A Partial List of Home Study Courses ACCOUNTING MARKETING ASTRONOMY BANKING BOOKKEEPING [BUSINESS ADMINISTRATION BUSINESS ENGLISH BUSINESS LAW BUSINESS MATHEMATICS BUSINESS ORGANIZATION BUSINESS STATISTICS CHILD PSYCHOLOGY COMPOSITION :— Dramatic Elementary English English, Fundamentals of

sg 5 cision of classroom work often does better when he can Spanish work out his problems quietly alone. For many, also, the

possibility of adjusting study hours to other demands on time and energy is a distinct advantage offered under home study conditions. CONTEMPORARY NOVEL DRAFTING ART FINANCE ECONOMICS HISTORY DRAMA GERMAN GRAMMAR ENGLISH ITALIAN FRENCH

Write to the University for full information

LITERATURE:—

American Biblical : Feo sr re You will want to know more about Current English the scope and conduct of Columbia’s French Greek Home Study Courses, convenient fee Italian Juvenile

payments, etc. The University is prepared to send full information on request. Use the coupon below. If you care to write a letter briefly outlining your educational needs and interests it will enable the instructors to offer helpful suggestions. Latin Spanish

MAGAZINE ARTICLES MATHEMATICS MECHANICAL DRAWING PERSONNEL ADMINISTRATION PHILOSOPHY PHOTOPLAY COMPOSITION PHYSICS PSYCHOLOGY PUBLIC SPEAKING RELIGION SECRETARIAL STUDIES SHORT STORY SOCIOLOGY SPANISH SPEECH COMPOSITION

pemeemeneaenas -- MAIL THIS COUPON Columbia University, University Extension Home Study Dept., NewYork, N.Y. Please send me full information about Columbia Uni- versity Home Study Courses and their conduct. I am inter- ested in the following subject:

High School and College Preparatory courses are in- cluded in the Home Study Curriculum. Special bulletin on request.

Occupation

All of the Home Study Courses are not included above. If the subject in which you are interes- ted is not listed, mention it when writing.

Street and Number

City m nee

eee sce see eeeeeeseseesseseeses=

State Cl (Pp Ba 19-58)

H ‘ ‘ ‘ ‘ H ‘ ‘ ‘ H H s ’ ‘ § Name t ‘ : : , ’ H ‘ ‘ H 3 H ‘ t L

Page 142

144 Get Into This—the World’s Biggest Business IT NEEDS YOU! 6& Thousané Million Dollars paid every year for upkeep! Tremendous portunities for Big Raises ay QUICK for trained Man— clip coupon now. COMMmon schooling all you need. I give — Lifetime Employment service— Lifetime Consultation Service too! Pl Train You AT HOME Get my Free Book. Find out how you can become a Big Pay man in amazingly quick time! Keep your present job. Stay a. oo ag have to leaye our doorstep. as every ranch of Auto Work right én Bench, your own home. See how Itrain Receiving Set, zee Queene, and EASILY to BOSS 303 Wiring Dia- e Job, or GO INTO BUSINESS Chart where Pay comes UICK—and ere arts, up to $10,000 yearcaneasilybemade! Ignition and Make Money QUICK Socket Wrench amazi: Beok ‘ ° ROW See how hun rede of es Repair Outfit— eo tell ae 2 also Automotive Boney. Media Businesser of their own Fate or z ve ut almost rig 7) aztra Weeks O& MONTHS! — Charge. B. W. COOKE, Directing Engineer, Chicago Motor Training Corporation Dept. 925 MAIL THIS B. W. COOKE, Directing Engineer, Chicago Motor Training Corporation, Dept. 925 1916 Sunars ide Ave., Chicago, Ill. Send me FREE Au fi Auto Book and proof that I can become -<

| 1916 Sunnyside Ave., CHICAGO an Auto Ex- gert at home in spare time. Also send your 6 Outfits Offer. It is un- itood that this obligates me in no way

ELECTRICITY LEARN IN 12 WEEKS Finlay method of practical Electrical in- struction (now in 24th successful year) pre- pares you for big paying position in 12 short weeks. Learn by doing actual electrical work. Earn up to$25a day. Send at once for Free Finlay Catalog and full details re- garding this wonderful business. Enroll anytime. Completely equipped shops and laboratories. Faculty of highly trained experts. Cer- tificates awarded. tudents assisted to positions. Success can be yours. Write today and get the facts. Ask about One and Two Year Courses. Finlay Engineering College 664 Finlay Bidg., : Kansas City, Mo.

‘It’s Brains Against Brains —Fighting Gorillas!”’ (Continued from page 143) orange, quickly concluded it was beyond her reach, scratched her ear for a moment, then examined one of the boxes reflec- tively. Suddenly the idea struck her. She dragged the box under the orange, climbed up on it and tried to reach the fruit. It was still too high. She sat a while in deep thought, then got a second box and piled it on the first. She seemed to recognize that she had found the method, for when she failed on her second attempt to get the orange it took het but a moment to pile the third box on the other two, clamber up and seize the fruit. AN OTHER test consisted of placing an apple inside of a length of drainpipe, out of her reach, and leaving a pole lying where she could get it. After trying to reach the apple with her hand, she took only a short time for reflection before getting the pole and poking the apple out of the pipe. .A memory test which she successfully passed was letting her see some food of which she is fond placed in a glass jar and buried in the sand, then several days later letting her loose in the neighborhood of the cache. She remem- bered and quickly unearthed the jar. Most of the deaths of gorillas in cap- tivity, Mr. Burbridge believes, have been due to too close confinement, improper feeding and the contracting of diseases, such as colds, pneumonia and tubercu- losis, because of too close association with people. Miss Congo has been kept out of doors ever since she came to Amer- ica and has never been ill. When she was brought to Jacksonville she weighed forty-five pounds; eight months later she had grown to one hundred pounds, under the careful feeding of Mr. Burbridge’s sister-in-law, Mrs. James D. Burbridge, of whom the gorilla is especially fond. Since the normal span of life of the gorilla is believed to be about the same as that of man, Miss Congois not expect-' ed to reach maturity for another eight or ten years, and her captor and foster mother hope that she may furnish a fruit- ful field for another fifty years and more for the study of her mysterious race and the relationship between’ man and the beasts.

Gas Bought by the Cylinder YLINDERS of compressed gas now take the place of natural or artificial gas for cooking, in many parts of the country where no city main is available. A cabinet-enclosed supply unit is installed outside the house, in some inconspicuous place at the rear. This includes two cylinders of gas, one for supply and the other reserve. Stand- ard gas pipe connects the installation with kitchen range, laundry stove, clothes drier, or hot water heater. Operation, except for changing cylinders when the supply is exhausted, is entirely automatic. People using this service buy their gas cylinders from local dealers as they would a loaf of bread, simply buying a

new cylinder when the old is used up!

MONEY MAKING OPPORTUNITIES SECTION

LEARN BY DOING Every phase of all ranches ELECTRICITY taught by Actual Practice In America’s foremost and oldest institution for trade training No Books Used ; Individual Instruction Start Any Day Write for FREE 64-page catalog THE NEW YORK ELECTRICAL SCHOOL 40 West 17th St., New York City

When you Just as the Natives Do

Play in Half Hour After you get the four Evenif you don’t know easy motions you pla: one note from another, miouschordswith the 52 printed lessons very little practice. No and the clear pictures previousmusicalknowl- make easy to learn edge necessary quickly. Payas youplay. Free Guitar Write at Once and Outfit in Genuine Seal Grain You'll never be lonesome with wapeibeie Waa eam as you en- pa Hawaiian Geer. roll. rt o buy—everything rite for Specia' er ai furnished. No delay. ‘ terms. A postcard will do. ‘Act FIRST HAWANAN CONSERVATORY of MUSIC, Inc. 9th Floor, Woolworth Bidg., Dept. 146 New York, N. Y. Approved as a Corr e Schnot Under the Laws te of New York FIVE TUBE RADIO aan $500

Ed AGENTS WANTED BIG COMMISSION Demonstrating agent wanted; every county, Ex- clusive to right man. Sell what public wants— five tube, long distance, loud speaker radio with single dial control. Price within reach of all, $25,00 retail sliberal discount to agents. Sell in spare time—evenings. Noselling or radio experi- ence necessary. Territory going fast. 100 page Radio Book FREE. Write today—don't delay. C, F. FISCHER, 122 W. Austin Ave.,Chicago |

Have You An INVENTION? Ifso the WORLD PROGRESS will send you upon request sample copy Free containing Suggestions to Inventors as to Inventions Needed. We invite manufacturers to address us regarding inven- tions they want. Subscription for one year 60 cents. WORLD PROGRESS PUB. CO., INC. Reem 202 Victor Bidg. Washingten, D. C.

SIGNS and SHOW CARD PAINTING MADE EASY ss To produce really good signs, show cards, and lettering work, allyouhaveto dois trace around the Letter Patternand thenfillin vour tracing. Anyone can do it. 3 Sizes and styles for all practical S— uses. Write for free samples. John F. Rahn, D2120 N. Neva Ave., Chicago, II.

Decem4 the I detec a pal Jogic: whic! ing } A this. one The boy victi beer app his | cons lad. wit! wh tru the pla the inn cor

Page 143

—— : New Crime Remedies (Continued from page 15) the records of Dr. Wechsler’s emotion detector, the truth serum results form a part of the evidence which a psycho- logical detective can accumulate and which he must take into account in form- ing his conclusions. at A case of Dr. House’s illustrates this. A boy was accused of having been one of two men involved in a holdup. The other man was shot dead and the boy was arrested on the spot, the two victims who had been attacked having been policemen in disguise. The case was apparently a clear one. Dr. House tried his serum on the boy, with the latter’s consent. NDER the drug there came out an al- most unbelievable story of how the lad had been induced to join the excursion, without knowing its purpose, by the man who had been shot dead. The boy was truthful. Facts already in possession of the police fitted into the tale. They ex- plained the story; the story explained them. The lad was freed, thus saving an innocent person from virtually certain conviction. _ Another famous murder case which ‘thas cost an enormous sum and is still not settled to universal satisfaction is the Massachusetts case of Sacco and Van- zetti. On April 15, 1920, a paymaster was held up and killed. Sacco and Vanzetti, who are anarchists, were arrested, tried and convicted. Alibis presented for them were rejected, although on the face of the record they seem strong. The case has been re-opened recently for a new trial. Here we have a case in which the psy- chological examination of the accused men would undoubtedly be useful. It is almost unthinkable that these two men, neither of them experienced in deceit, could go through a careful examination by a skilled psychologist without disclos- ing facts which would help vitally to determine their guilt or innocence. If these men are innocent, an examination of this kind might save them from terrible injustice. In fact, more than one instance of miscarriage of justice in the past could not have happened had psychological ex- amination of prisoners been in vogue. N NOVEMBER, 1917, Mrs. Annetta Morello killed herself in her room in Newark, New Jersey, because her husband had been drafted and was going to war. Her husband was in the room at the time. He was arrested and examined, in Italian, through interperters who were not sufficiently familiar with the dialect which he spoke. He was convicted, the inter- preter having reported that he confessed, whereas he had really tried to say that his wife had committed suicide. Not until 1926 was the mistake discovered and Morello freed, after eight years of jail. In at least some of these cases devices like Dr. Wechsler’s would have helped to extract the real truth from the witnesses. In others, the second kind of psychological investigation could have been employed, the kind which helps us to decide whether the crime and the suspected criminal are psychological mates. (Continued on page 146)

\

\\ Extension }.

oO. Cc. e. oe MILLER Ay Diresior ’ F Work

Outfit Given beet tn am hey board. table, triangles, T Square, ink, pro- tractor, etc., given without charge,

will make this contract with you

| O. C. MILLER 'd ‘ ie you enroll for my home-training in DRAFTING, I agree to give you: 1. Complete instruction by my new practice method. 2. Costly professional outfit shown above. 3.I WILL HELP YOU GET A GOOD JOB AND A RAISE IN

PAY— BA 4. Or I'll re- fund every centof your money.

}

MONEY MAKING OPPORTUNITIES SECTION r "Prepare at home for a well-paid drafting job B

145

EFORE you put your time and money into any kind of train- ing, make sure there are plenty jobs to be had when you're ready for them. That’s why men go into Drafting. 70,000 jobs ad- vertised in 12 months. Big salaries, Fascinating, easy work. short hours and unlimited opportunities for advancement to executive positions. Here’s “white collar work” that con- trols all building, manufacturing, public works. Called the Ideal Proféssion for Men because it offers the greatest op- portunities for, success, Drafting Made Easy for You We have developed a new, one-step-at-a-time method which makes Drafting prin- ciples easy to understand. Even men with only com- mon schooling make rapid progress with this instruc- tion. Right from the very beginning you do actual Drafting room jobs. And by a wonderful new system you learn without copying, you see why every step is done, and so you become a Drafts- man, not a tracer. Training Backed With Nation-wide Free Job Service The American School now offers its students and graduates, with- out cost, the services of an effi- cient Employment Department which keeps in touch with the employers of Draftsmen all over the United States. We have placed hundreds of men in good Drafting positions. The demand for Draftsmen in all lines at all times exceeds the supply. This is the work to get into. I will show you how, and help you make a success of it. Real Draftsmen go quickly to the top with the backing of this mil- lion-dollar Institution. Real Draftsmen SPECIALIZE The big money in Drafting goes to men who specialize in Machine Design, or Elec- trical Drafting, or Architec- tural Drafting, or Structural, or Automotive. It isn’t enough merely to know gen- eral Drafting practice. You must know how to calculate and design and plan original work to fill the kind of Drafting posi- tion that pays $60 to $125 a week. The American School, for 29 years a leading institution teaching Engineering by home- study methods, now Includes this specialized training In the com- plete Drafting course. No-Profit Price Easy Terms This wonderful, more com- plete, simplified, rapid, up- to-date instruction in Drast- ing offered at very low tui- tion, easily within reach of the untrained man who needsit. Small monthly pay- ments make it easy for you to prepare for a fine ft- ing position at a big increase over your present salary.

Look into this opportunity. Get my free book, Job and sho Raise offer w you how to turn part time into real training and for a quick! Let me yEapeebs Mail this coupon for my amazing offer!

0. C. MILLER, Director gf Extension Work 0. C. MILLER @ American School, De 975 Drexel Ave. Director of Extension Work ag magnon peli se Please send me Free Drafting Book, Job > Raise offer and complete information American School about preparing for a fine Drafting Job at @ home in spare time. Dept. D-975 § =< Drexel Ave. and 58th St. 8 aes CHICAGO = g

Page 144

146 $50 to $250 a Week Paid to Good Cartoonists! You Can Easily Learn This Fascinating Profession Right at Home in Spare Time. Send for Free Booklet Explaining Method. HERE isn’t a more attractive or highly paid profession today than cartooning. Millions of dollars are spent every year for good car- toons by the 20,000 or more_news- papers and magazines in the United States alone. Capable Cartoonists earn $50 to $250 a week. Fontaine Fox, Briggs, Bud Fisher, Sid Smith and others MAKE MORE MONEY than the presidents of many corpora- tions. Think of it! Quick, Easy Way to Learn Cartooning Yet of all the professions cartoon- ing is now positively one of. the easiest to learn. You don’t need to know a thing about drawing. Through our amazingly simple meth- od many who never dreamed they could draw have easily learned cartooning. You too—without any apparent talent at all— can easily learn to dash off side-splitting cartoons that may mean ease and independence for you within a surprisingly short time. You learn mght at home, yet your work receives the personal correction of our success- ful cartooning instructors. Many students actually sell enough work during their training to pay for it. Mail Coupon for Free Book Learn more about the wonderful money- making opportunities in cartooning, and how this method makes it easy for you to learn. Read about our students—their success —what they say—how easy it was—actual reproductions of their work—how they made big money while studying. Booklet entirely free. Send for it NOW. Washington School of Cartooning, Room 2412-D, 1113-15th St., N. W., Washington, D. C iidiiinertnn School of Cartooning, Room 2412-D, 1113-15th St., N. W., Washington, D. C. Please send me without obligation, your illustrated FREE BOOKLET on Cartooning. I Me ~ aera (Write name plainly) NE. ry ee ee Pee nek AE ae ee eee BORED. .u..-.... New Crime Remedies (Continued from page 145) In a famous British case of eighteen years ago, the case of the murder of Marion Gilchrist, tests of this kind would probably have saved an innocent man from prison—or hanged him if he was guilty. Marion Gilchrist was an elderly spinster who lived alone in a small apartment in the city of Glasgow, Scotland. On De- cember 21, 1908, she was brutally mur- dered in her home. A man was seen run- ning away but was not captured. Four months later a man named Oscar Slater was arrested, convicted and sentenced to be hanged. There were grave doubts of his guilt, which was indicated almost en- tirely by circumstantial evidence in which it is quite possible, even at this late day, to pick serious flaws. Influenced by this fact, the Home Secretary, who is the par- doning authority in the British Isles, commuted Slater’s sentence to life im- prisonment. So far as I know he is in prison yet. F SLATER was innocent, a fearful mis- | carriage of justice has occurred. If he was guilty, there was still a miscarriage, for in this case the Scottish law required that he be hanged. An experienced detective or criminal judge acquires, of course, instinctive power of judging this ability or inability of a certain suspect to commit a given crime. “That’s not his kind of a job,” they say. Usually they are right. It is merely long experience and acute observa- tion of character. What a series of psy- chological tests can do is to supplement this; to do it better and more certainly. The tests used for this purpose aresimi- lar to those now used by many busi- nesses in selecting employees. They de- termine the habitual quickness of move- ment and of reaction to stimuli, like noises or touches. They test general intelligence, also, and mental stability of the witness or his tendency to get excited in an emer- gency. Still others test his muscle con- trol—a matter of importance, for ex- ample, in deciding whether he could fire a revolver accurately during a moment of excitement. EGINNINGS in these psychological methods of criminal examination have been made in several cities, notably in Berkeley, California, where Police Chief August Vollmer is well-known for his close contact with the scientific departments of the University of California and for his use of science of all kinds in the city police work. In some of the larger cities, nota- bly in Los Angeles, Calif., and in New York City, some tests have been made with such methods. Every court or police station having to do with many criminal cases should pos- sess its psychological laboratory, equipped with apparatus for the general testing of character, and in charge of a com- petent and experienced psychologist. In cases like the Hall-Mills case or the Sacco- Vanzetti case the savings to the state | would be thousands of dollars, now spent in the examination of witnesses who dis- close nothing important. MONEY MAKING OPPORTUNITIES SECTION December, 19% I Didn't Think So Much Fun’ “I do not believe any but those who have gone into this work can really appre- ciate the joy it brings. All my orders have been sold. In four months we have taken in $827.65.”’ Would you like to make $10 to $25 at home and thrill to the joy of decorat- ing lovely gift wares? You need no special ability. Other women with no previous experience are doing it. Fireside Industries teaches you amaz- ing new method—makes everything easy. Fascinating Spare-Time Work In your leisure time, and under per- sonal direction of Gabriel Andre Petit, you decorate parchment shades, candle sticks, table runners, book shelves, baskets, book ends, and countless other art objects so much in demand. Work is just like play. Through membership in Fireside In- dustries, you get articles cheap—sell them at big profit. We furnish artist's outfit without extra cost to all members. pos BE AUT IFS. NEW BOOK "ON ECORATIVE ARTS Gives full details of this con new source of spare- time income. Illustrates beautiful home accessories you can decorate. Explains simple method which enabled women who started work for pastime to build up steady incomes. If you long to express your personality a new way—if you want to turn your spare time at home into $10 to $25 a week—write for this 32-page book today, sure. Enclose 2¢ to help pay postage. There's no obligation at all. Dept. 51-W. Adrian, Mich, aoe \ e one sf » Hawaiian Guitar ‘ Have you seen the latest “, - Jazzinstrument? Every- 7 body is talking about the curious, unusual} **Jazzitha.’® If you hear ft you will want to own es one. yI— an music! Play all the song hits immedi- ately: _absolutely no instructions or lessons necessary music is written in numbers, Makes an ideal gift. The ‘‘Jazzitha’’ is made of fpe ste ined hard wood with aanecially designed me cana box. Hande sorely dec miei ited dee Beautify fn finished in lacquer— sin length. Com and pick. Send No Money your name and address when 8 Vv postman only $1.47—plus a few cents extra for postage. Outside of U. S. send check or money order. GIVEN _ witheve instrument we —will include 3 extra Jazz- AWAY J itha strings worth 25c. JUST OUT 5 Books of popular song hits. 5 latest songs in each book written in number...........+++ 25c each. ‘THE JAZZ STUDIOS, 2512-41 Ave: “9 Dept. 522 LONG IS! ar | tk ee Ed the RE (abese, BISU SASS By we mee om we ae HT 1 LAND CITY, N. ¥ ) STUDY => GPGreer a STUDY AT HOME al er. a+ men a: wo and big suceess in business a and Pat life. J independent. Gi ¢ res ter ©) an ever before. (rations ‘te. head aded by men Bie care. legal es ona trained men earn 000 to $10,000 Annually train at hi — guide pare Lime mgr ro You bee a ok — ore dar. A ty foun Ca ing attorneys of Library We f furnish all eons materia, Enel inc} —— fourteen: avolume Lae easy te e 108-; Law Guide™ “alg TeSvidence booke fr ~2. LaSalle Extension University, 1283-L Chicago The World’s Largest Business ing Institution ATTEN) “ompleteConservatory urse by Mail UNDER MASTER TEACHERS : . Wendertol ten atady music yo under erican and Eu con wo Kamer En- | pene by Paderewski. Masterteachers guide and coach you. Lessons a marvel of simplicity and completeness. ng course you are interested in:Piano, Guitar Banjo ot Reed »PublicSchool An Man Vil Comet Map ee Guitar, Banjo or Reed Organ Sines naliaiananeine seen pal Myers Bido.. Chicago Unusual opportu- r. rus. a esman nity is offered for anarenstve, ambi- tious, hustling men to sell an old established high-grade, guaranteed, fastest selling line of Sanitary Twisted-in Wire Brushes, sold direct to the Home. We have openings for experienced brush men as managers in all territories. We want live wire, energetic Go-Getters. We pay larger commissions than any other Brush House in the Country. If you want to earn some real money, it will pay you to write us immediately fer our proposition WIRE GRIP SANITARY eRusH CORP., EW YORK CITY 15 MERCER STREET focu eo oS o's -— *D rh Oo Th of

Page 145

errata ZT se ,¢ *' FRANKLIN INSTITUTE, MAIL CARRIERS * Se taeh ame dre - Sirs: Rush tome without charge: e (1) Specimen Railway Joel Clerk See countr eo 2 pak deine tl i 3° fh — Baa ge $1 700 to $2700 Year your y ot sa full particulars telling how to BIST Up OEM uron ot” ane... MEN—B0 S, 17 UP po A, ag a NGO de ccic esa chahcannanele weeds

Steady Work. No Layoffs. Paid Vacations. ~ pa Ee re te!

| j | | } 2 en.

Page 146

148 CHEMISTRY Learn at Home Tue Chemical Industry now ranks fourth among the industries of the United States and it offers a splendid opportunity for ambitious men. Arthur D. Little emphasized this very point in his speech before the American Institute of Chemical Engineers when he said: ‘Industrial developments along new lines are everywhere in progress and they call upon the chemical engineer for new equipment and new methods of production and control.” One of the best ways for ee to prepare: for a good position in this fascinating field is through the home- study courses in Chemistry offered by the Interna- tional Correspondence Schools. These courses are complete“and practical because they were prepared by some of the best-known chemists in this country, including: ALLEN Rocers, B.S., M.S., Ph.D.—Head of Depart- ment of Industrial Chemistry. Pratt Institute. Anprew M. Farris, B.S. — Consulting Chemical Engineer for the Tennessee Copper and Chemical Cor- poration; American Zinc, Lead and Smelting Co.; Ameri- can Zinc Oxide Co., and the Baugh Chemical Co. L. M. Totman, Ph.D.—Formerly Chief Chemist, Wil- son & Co. Now Vice-president, United Chemical and Organic Products Co. BrapLey Storenton, B.S.—Head of the Department of Metallurgy, Lehigh University. OwEN L. SHINN, Ph.D.—Professor of Applied Chem- istry, University of Pennsylvania. Qualitative and Quantitative Analyses Outfits are sup- plied with these I. C, Courses at special prices for your laboratory work at home, and the courses are so arranged that you get just the help you need to secure a good position in the work you like best. Just mark and mail the coupon and we’ll gladly send you Free Booklets describing the I. C. S. CHEMISTRY CovrRseEs or any other course in which you are interested. Mail the Coupon for Free Booklet INTERNATIONAL CORRESPONDENCE SCHOOLS Box 7613-E, Scranton, Penna. Without cost or obligation, p'ease send me one of your booklets, and tell me how I can qualify for the position or in the subject before which I have marked an X. |_| Analytical Chemistry OD Analytical and Industria! {_] Chemical Engineering -_ Chemistry {_j industrial Chemistry (C1Shert Chemistry Course CJ Metallurgical Chemistry Ci Pharmacy Also courses specializing in the Chemistry of the following industries {] Manufacture of Leather (0 Manufacture of Iron {_] Manufacture of Gas (J) Manufacture of Steel {] Manufacture of Cottonseed Oil () Manufacture of Sugar () Manufacture of Petroleum (J Manufacture of Soap [Jj Manufacture of Sulphuric (J Manufacture of Cement and Hydrochloric Acids (J Manufacture of Paper (Electrical Engineering (C0 Electric Lighting _) Mechanical Engineer () Mechanical Draftsman (J Machine Shop Practice (_} Railroad Positions CJ Civil Engineer (J Surveying and Mapping (J Metallurgy 0 Mining OSteam Engineering OArchitect ORadio (J Architects’ Blueprints Contractor and Builder (J Architectural Draftsman {_) Concrete Builder (J) Structural Engineer () Airplane Engines C) Mathematics SCHL est iuch.+ pibrsetshvebayaeaiieecasesysesecbunedestustGrodebesvsesesessooes I III, «ccd aiisatahonatiesenptambnabelontdacasapebienedacrsnevinsorceceons City PREPARE FOR AN ART CAREER: thru the only school operated asa department of a large art organiza- tion. Commercial Artists trained the ‘“‘Meyer Both Way’’ earn as high as $10,000 per year. We today have hundreds of students who had pre- viously studied in other art schools. Why? Because your instruction is based upon our everyday eé - ence in meeting the art needs of leading advertisers. Home study instruction. Write for illustrated book teiling of the success of our students. MEYER BOTH COMPANY Michigan Ave. at 20th St. (Dept. 35) Chicago, Ill. They Can Fly with Their Eyes Shut (Continued from page 21) I was absolutely as well as hopelessly lost. “I dropped a flare, and in landing hit a tree. I was in Bloomsburg. “Almost exactly one year later—the night of the Dempsey-Tunney fight— after flying blind for nearly two hours in the fog, I came out of it; again I was over Bloomsburg. But this time I knew exactly where I was.” What Captain Chandler considers his narrowest escape also occurred near Bloomsburg. Having passed over the city, he lost his direction in the fog. He turned and again flew over the city. Then he dropped a flare. The magnesium light disclosed an oat field opposite Rupert, in which he madea perfect landing. Getting his bearings quickly, he pre- pared to take-off. By this time a crowd had gathered and stood watching him. HANDLER shouted a warning and started off. The plane bounced unevenly over the oat field, and began to rise. Too late, Chandler realized that the oat stalks had become entangled in his landing wheels and were diminishing his speed as he rose. Looming up ahead, too close to avoid, and too high to clear with his retarded plane, was a huge tree. Beyond was the Susquehanna river. A cry of dismay from the spectators, a crash of rending timber, and the great plane had rushed headlong into the top of the tree. Carrying top and limbs with it, the ship plunged toward the river. It staggered, then landed on its side, twenty feet away, in four feet of water. Campers rushed to the rescue. They found Chandler amid a heap of branches and wreckage. The right wing of the plane had bent over, pinning him tightly. Fortunately his head was out of water, but he was bleeding profusely. Portions of the cockpit had to be chopped away before he could be released and carried to a hospital. There it was found he had suffered a fractured skull, a broken nose, and lacerations of the head and face; yet over the protests of the doctors he directed from his bed the disposal of his entire cargo until it was in the hands of the postal authorities. : EAN SMITH can boast of being the only air mail pilot who ever ran down a cow. While flying the mail route from Chi- | cago to Omaha, he stripped his gears and was forced to attempt a landing in an open field. It was a cow pasture. The wheels had barely touched the ground when the cow stopped directly in the path of the plane. Plunging ahead at eighty miles, the nose of the machine caught her squarely. In a shower of blood, the plane did a cartwheel, twisted out of shape, and landed on its back. In flying the Cheyenne westward route, Captain Chandler’s nerve and resource- fulness saved him from what might have been a fatal accident. As he rose from the field. at Cheyenne one day, the left wheel on the ship’s landing gear flew (Continued on page 149) MONEY MAKING OPPORTUNITIES SECTION December, 19% Practical educators for mag all Engineers, Firemen, Machinists, Electricians and engineer students. Eight valuable, up-to- 2 date Guides treating on oe Goo and practice be ond ‘ll. esta shiistemensoeeins i Us A COMPLETE HOME STUDY CouRSE AND REFERENCE LIBRARY 8 pocket numbers with Ready Reference Index.8754 pages. 4750illustrations. Easy toread, Highly endorsed. A good help in securing Engineer’s License. Price $12: —— terms, $1 per month. Free Trial. : ORMATION: — In A Handy Form. Answers to Your Questions and Problems. Here is a partial list of the subjects covered:— Engine Principles, Valve Setting, Pumps,Corliss Engines. Uniflow Engines, ao Engines, Contractors Engines, 1 Locomotives, Marine Engines, Turbine Engines, Gas Engines, Oil Engines, In- dicators, Producers, Aviation, Steam, Fuel Economy, Boiler Construction, Fir- ing, Oil Burners, Stokers, Boiler Repairs, Pipe Fitting, Heating, mofrigoration, Elevators, Dynamos, Motors, Lighting, Wiring, Electrical Diagrams, Radio, Elec- trical Reference and Calculations. SHIPPED FREE Not a cent to pay until you see the books, No obligation to buy unless you are satisfied. Fill in coupon im pencil. Send now—today—get this standard library for Engineers and Mechanics, ee ee ee ee ee FREE Dora ago nd me BCI Le AND MECHANICS GUIDES. 8 COUPON numbers, $12, for free examination. in 7 days, then $1 monthly until $12 is paid. If satisfactory, I will send you $1 f a Violin, Tenor > Hawaiian Guitar q y lan Gi r, Banjo, Cornet, Heise SanjoUkulels, Gylar. ‘andolin or Banjo ae in. You wil oO be — to own any one ese instruments and we will give youone wi it cost. A few cents a day for lessons is your on! aly xpenee. system of teaching is 80 nap 4, at you can play several pieces by note with the first four lescons. We guarantee success or no charge. In- strument and lessons sent on one week's free trial. Write for book- today, no obligation. Over 200,000 satisfied pupils. CHICAGO CORRESPONDENCE SCHOOL OF MUSIC, INC. *1632 North Halsted Street, Dept. 249, Chicago, lilinois NI Write today for WaYeyey.2 Wate a 123-pege book, “THE LAW TRAINER aL Sa: Ge acksione Caras OaRiee Wa Lint SG URaS RET Blackstone etaduates practicing law everrmhere. LL.B; degree te! ep enrollment. Moderate tuition fee. —o: Blackstone Institute, inc., ‘¢ 4753 America’s Foremost Non-Resident Secnool A 2c Stamp —will start you on the road to success. See Money Making Op- portunities on pages 134 to 165.

Page 147

Phar. oe rn SO

pecember, 1926

They Can Fly with Their Eyes Shut (Continued from page 1 48) off. Unaware of the loss, he continued on his fight in ignorance of the danger which awaited his descent. BSERVERS on the field at Cheyenne O saw the wheel as it fell, but they were powerless; for the plane was already ing out of sight. Knowing the risk that Chandler would take in landing with one wheel missing, they quickly eommunicated with the field at Rawlins, Wyo., over which the pilot would pass. It was fortunate for Chandler that he was not forced down before he reached Rawlins. Luck was with him. While passing over the field at Rawlins, the captain saw that he was being signalled to stop. “That’s peculiar,” he thought, as he circled around. Next he saw that the men on the field were holding some- thing up to him. Sailing lower, he recognized it as a wheel. He imme- diately inspected his ship and discovered the damage. The ingenious method he been generally adopted. “FIAHE possibility of such an emer- gency had often occurred to me and I had worked out a plan whereby I could land in safety,” he said, describing how he did it. “I brought the ship down in such a manner as to let the wind strike it from the left—the side of the lost wheel. At the same time, just as I touched the ground, I dropped the right wing slightly, keeping the tail high. “In this manner I rolled about fifty feet on one wheel and greatly decreased my speed. As the left side began to settle, I turned,at first slowly, then sharply totheright. This produced the same result ‘| as does the act of turning an auto sud- denly; it tended to upset the plane to the right and put all the weight on one wheel. “By this time so much speed had been lost that I was unable to keep the butt of the wheelless axle out of the ground any longer. I came to a full stop without damage to the ship or myself.”’ WHILE the air mail pilots already have taken aviation out of the hit or miss class, they foresee still greater strides in the near future. They predict a time— perhaps within a year—when they will be able to fly regardless of weather, keeping accurately to any course. That will be possible through the use of the radio compass, constant weather reports, and multiple motored ships. A plane with multiple motors will have little to fear from engine trouble, and forced landings from that source will be all but elim- inated. The radio compass will tell them, by a system of signals, whenever they are about to stray from the route. But whatever the perfection of the in- struments, the success of the air mail will always depend on the courage and deter- mination of the pilots. They will always go forth to do battle with the fog, the wind, the rain, and the ice. The instru- ments can tell the aviator what to do;

but it will always be up to him to do it. employed to meet this situation has since |

MONEY MAKING OPPORTUNITIES SECTION 149

PLAY A SA’ Ill 4 Teach You py LOUIS Popular! Amaze Everyone Play for Money or Fun ONDERFUL music from a saw — Sweet and mellow like a rare old violin. Tone effects that are positively startling — all so unexpected that nothing compares with it in winning instant popu- larity in your social group or as a salaried entertainer. And it’s so easy! oe to prove how quickly you can learn, ll send you a genuine ‘‘ Musical Saw” (special temper, process patented) for FIVE DAYS’ TRIAL. I guarantee that in 24 hours you can play tunes like “Old Black Joe” and “Home, Sweet Home”. Then the latest jazz and song hits, oper- atic and classical music. Amazinglysimple = ¢_ 3. yussent. — no notes to read, no dreary practice. _Fienger Artist on the Musical Saw, Thousands Successful by My Method

Just three short, simple lessons reveal every ville Stars and secret of my 12 years’ success asa professional = High. Priced En- saw musician—secrets with which I havetaught thousands. Many of my pupils are on the vaude- ville stage, playing in dance orchestras, making big money as entertainers. Let me prove that you, too, can quickly play like a professional— amaze your friends and always be in demand

at parties and entertainments. ies and i ‘4 Phonograph Record FREE! ‘ Double-disc, demonstration-size Phonograph Rec- ord of beautiful saw solo and duet. Two beautiful ! selections, eye! amazing to anyone who has q never heard the Musical Saw and its e c.J sweet tone. Send 10c to cover handling Mussehi t and postage. However, if you have al- ‘ — { ready heard the Saw, and do not want ; xmas the record, ask only for my big FREE MUSSEHL | TRIAL OFFER with which all my pupils &WESTPHAL . have made their start to fame and money. 267 W. Water St. No charge; sent postpaid. ort Atkinson, Wis. < Without obligation F7 to_me, send me, postpaid Full particulars about ’ OFREE TRIAL OFFER. OPhonograph record (Send 10e to cover handling and postage if you want record). 1!

Robert 8

Alter, Charles Guglieri, ‘‘Bud’? Gamble {s broadcasting celebrity, booked to play saw paying his way a- has delighted audiences solos in adway round the world with of six leading stations, (New York) motion the Musical Saw. Is includingan arance f a picture thestre, pow in Europe. from WSN “3 - shipLEVIATHAN’’. 4

MGGIEGA. ccc ccnscce

Mussehl & Westphal Fort Atkinson,Wis. Town and State

ee ee es ee oe ee ee we oe a ee a

Page 148

Big Bidirice Paid Automobile Experts Fastest growing industry in U. S. A. offers unusual opportunities to trained men HE automobile industry is one of the biggest and fastest growing industries in the United States. There are more than 18,000,000 cars registered in this country and the number is increas- ing every day. The best way to pres for success in the auto- mobile field is to study, and there is no better way to do this than through a home-study course with the International Correspondence Schools. We say this because many of the leading figures in the automobile world today are former I. C. S. students. The list includes Jesse G. Vincent, Vice- president of the Packard Motor Car Co.; Walter P. Chrysler, President of the Chrysler Corporation; E. V. (‘‘Eddie”) Rickenbacker, of the Rickenbacker Motor Car Co.; and Hiram Walker, Chief Engineer of the Chandler Motor Car Co. Just mark and mail the coupon and we'll send you information about the I. C. S. Automobile Courses or any other course in which you are interested. Write for Free Booklet CC ee eee ee ee ee eee ee eee eee INTERNATIONAL CORRESPONDENCE SCHOOLS Box 7614-E, Scranton, Penna. Oldest and largest correspondence schools in the world Without cost or obligation on my part, please tell me how I can qualify for the position or in the subject before which I have marked an X: Complete Automobile Course [) Gas Engine Operating Automobile Electric Equip- () Complete Gas Engine ment Course Electrical Engineering Electric Lighting IMechanical Engineer Mechanical Draftsman Machine Shop Practice Railroad Positions ie Engineer Blueprints Builder Draftsman Pharmacy Surveying and Mapping Metallurgy ining Steam Engineering () Radio BUSINESS TRAINING COURSES Busi Mi t Salesmanship Industrial Management Advertising (Personnel Organization (Better Letters and Poultry Traffic Management cee Card Lettering Business Law Stenography and Typing (Banking and Banking Law (JBusiness English Accountancy (including C.P.A.)()Civil Service Nicholson Cost Accounting (JRailway Mail Clerk pooo0o0000000 Bookkeeping ‘common School Subjects Private Secretary High School Subjects Spanish (J French Illustrating SI acca tipapetih tcensancntcenenthnnsine+soccnicveostvevepssngpvecepasbebpheoccouconces Street Address....... SS EE. State sdeaicin ar ala Beco dos ss cenigndensinencbskpicesescbense if you reside in Canada, send this coupon to the Interna- tional Correspond Schools Canadian, Limited, Montreot >) Soi Tatas : ef Milwaukee Pept. P. Ss. 1226, 163 Oneida St., Milwaukee, Wis. MONEY MAKING OPPORTUNITIES SECTION Harnessing Thirty Million Horses (Continued from page 23) And the land could be tilled on a large scale with immense machines run by power now undreamed of even on our most modern farms. RAZING land would then be plenti- ful and feed for cattle cheap. Conse- quently more cattle would be raised, more leather produced, and consequently more and cheaper shoes turned out. Follow this advent of cheap power through any industry and the result will be the same. Starting at the mines, iron ore could be scooped up faster and cheap- er than is now the rule. Steel could be made cheaper, and consequently tools and machinery. Every article you wear, everything you eat, every utensil in your household and everything you use in your business would be cheaper and the aver- age man would be able to enjoy the luxu- ries now available only to the very rich. With cheap and abundant power no home, no matter how far removed from the centers of population, would need to be without the conveniences of the most up-to-date city apartment. Superpower is the next step. But even superpower systems will afford only a temporary relief for our needs. In the last quarter of a century the use of power in the United States has doubled, on the average, every nine years. Herbert Hoover estimates that we will need 30,000,000 more electrical horse-power in the next twenty years. He believes we can produce that much at the cost of from thirty to forty billions of dollars for new plants and equipment. But after that what? Where will the next several hundred millions of horsepower come from? That is the problem now facing science. And that is why science seeks to unlock the tremendous power in the atom. T THE same time inventors and engi- neers are busy, for before a new power can be applied to industry it will be neces- sary to find an economical and safe meth- od of distributing and storing it. It may be that when the new power arrives our present-day storage battery will have been replaced by a new storage device built on an altogether different principle. It may be that transmission wires will be discarded. Already experiments have shown that power can be transmitted by radio in a limited way. This method will surely be improved on. And when we learn to di- rect power to any point of the compass and to any distance, surely a new mechan- ical age will be upon us. Sensitive devices will be invented to catch and use this power. This already has been done with certain radio devices. Ships, airplanes and trains have been directed by radio. Professor Norris is only one of many eminent scientists who are hopeful we will get at the tremendous power of the atom sooner or later. When we do find it and the means of harnessing and distrib- uting it, we may look for an era of won- ders that will make our present mechan- ical age appear primitive. GET A HOBBY MAKE MODELS Start a Home Workshop “Model Making,” by R. F. Yates, describes the construction of model gas-engines, steam- engines, locomotives, boats, dynamos, tur- bines, railroads, guns, ete. Thirty chapters are devoted to models of various nature. It will help you to become a better mechanic. It_will help you to do hard soldering, soft soldering, lathe work, tempering, drilling pattern-making, etc. j This is a book every amateur or professional mechanic and model maker should have. ““Model Making” describes real engineering models, not toys. 432 Pages, 350 Illustrations. Practical, complete, easily understood. Price Postpaid, $3.00. POPULAR SCIENCE MONTHLY 250 FOURTH AVENUE, NEW YORK TWENTIETH CENTURY BOOK OF Recipes, Formulas and Processes This book of 800 pages is the most com- plete Book of Recipes ever published, giving thousands of recipes for the manufacture of valuable articles for everyday use. Hints, Helps, Practical Ideas and Secret Processes covering every branch of the useful arts are given. 10,000 a Formulas—The Best Way to Make Everything A book to which you may turn with confidence that you will find what you are looking for. A mine of information, up-to-date in every respect. Con- tains an immense number of formulas that every one ought to have, that are not found in any other work. Price, $4.00 Popular Science Monthly 250 Fourth Avenue, New York TT ee

Page 149

December, 1926 “The New Wonders of the Sea ' (Continued from page 26) ment through the blood of the female. They lose their teeth and luminescence and become almost blind. ; Deep-sea fishes have the most freakish forms. Part of the skeleton of the Stern- optyz, for instance, is visible outside of his body. He is bent downward, his tail far higher than his head. This is supposedly an adaptation to deep water pressure, as is the boot-shaped jellyfish that lives 8,000 feet down. The Argyropelecus is en- tirely luminescent. Its eyes, which are enormous and are on the top of its head, are turned upward. Did you ever hear of a butterflying fish? No, it isn’t a joke from Alice in Wonderland. It exists, and has wings beautifully colored, like those of a butterfly, in deep blue and vermilion and yellow. You wouldn't think paper would last long in the ocean, but the paper nautilus is a little octopus, and he lives in a delicate tissue paper shell in which he can float about on the surface. IHEN there are fishes with “panes of glass” in their stomachs, transparent membranes through which the internal organs can be seen. There is the Union Jack fish caught recently in South African waters, during the discussion whether the Union of South Africa should continue to use the British emblem and which got its name from the fact that the markings on the fish’s side resembled closely the Union Jack. All fishes are not as cold as they look, and they do make love. Professor Julian Huxley has been peeking, and has seen them. Crabs aren’t really crabbed, he says, for he has seen the male fiddler crab courting. When the lady crab comes along, the gentleman stands on tiptoe and holds aloft a highly colored claw. If she passes him by the first time, he tries an- other attitude. Male spiders carry flies, wrapped up, to their lady loves; but the later sometimes eat their husbands onthe honeymoon. The marine bristle worm is lured from its home by the moon, and seeks the female, to sport in dances by moonlight. Imponderable are the ways of nature. iy of the greatest wonders of the sea is plankton, the teeming life best known as causing oceanic phosphores- cence. Those waves that seem just water, whether blue, or green or gray, are often full of minute living things, each with its own individuality, each living out its little life. Plankton is the star dust of the sea, floating life that drifts with winds and currents, and at night glows and glimmers as the ship ploughs its way along. It is twenty-five times as efficient a light pro- ducer as an electric bulb. It makes the sea an opaque, oxidized liquid as different from water as tar is from glass. It resem- bles in appearance a rich pink jelly. Its numbers are as the sands, uncountable. A gauze net with an opening a yard wide, yielded to Beebe on the Arcturus a haul, one 150th of which he estimated to number 271,080. (Continued on page 152) MONEY MAKING OPPORTUNITIES SECTION 151 A NATIONAL CALL For Men. Fire Prevention Experts Making $5,000 to $10,000 a Year OW, anew way to fight fire is sweeping the country. Anamazing new chemi- cal—absolutely harmless to rugs, furniture and human beings—multiplies itself hun- dreds of times in a smothering vapor blanket that snuffs out fire instantly. FREE Training We start you. Train you at home, free. Give you a 90-page manual that covers every point. Tells you exactly how to sell. We make you a Fire-Prevention Expert Fyr-Fyter hand pumps shoot this liquid 20 to 30 feet—the most effective fire-fighting force the world has ever seen. A Great National Movement This new way to fight fire can easily mean $10,000 a year to you. All America is turning to it. Every month, by hundreds and by thousands, homes, facto- ries, hotels, new buildings, and institutions adopt Fyr- Fyters. Great organiza- tions like General Motors, Firestone Tire, Ford Mo- tor Co., Standard Oil and hundreds of other large con- capable of earning $5,000 AGENTS to $10,000 a year or more. A brand new extinguisher at a startling new low price sells fast to stores, factories, schools, garages, homes, farms, ete. Everybody wants fire protection at this amaz- ing low price. Agents break- ing all records—making any number of $30 and $40 days! Payne, Ia., averaged $20.77 for 217 days. Greene made 47 calls and sold 35. Join the biggest money-makers in di- rect selling. You can easily make $15 a day with this one extinguisher alone—and up to $10,000 a year, picking up big quantity orders. Mail coupon quick for full offer. FREE Book Let us send you a free book, “Building a Perma- nent Income.” See how hundreds of men have dou- bled their incomes. Read how scores of men like George, Viles, DePries, Hickey, Gill, Pollock, etc., entered this field and sud- denly found themselves making $100 to $300 every week. How Baker, Oregon, 68 years old, who can work only occasionally, often makes $25 to $30 a day. Make This Test cerns are using the new Fyr- . Fyter, and continue to purchase it regularly. Unlimited Opportunity The demand is enormous. The surface has hardly been scratched. Thousands of factories, churches, stores, offices, garages, schools, etc., etc., want Fyr-Fyters. Countless owners of new buildings will buy almost without question. One city block is capable of sales running into thousands of dollars. Everybody wants fire protection. It costs only a few dollars. It often pays for itself in lowered insurance rates alone. Millions read of fire catastrophes daily. The newspapers are full of it. 17,000 lives are lost yearly. Every two minutes a building burns down. Millions see these fires daily. Every fire can mean $100 to $1,000 to you. Let this great national movement to wipe out fire sweep you into one of these $5,000 to $10,000 jobs! Full Time or Spare Time Experience is not necessary. There are various ways in which men in every walk of life can cash in on this outstanding o portunity—spare time or full time—big city or small rural community, anywhere. See how easy it is to start. We require no capital. We do not demand all of your time. Do not make the mistake of trying to judge your earnings as a Fyr- Fyter man‘ until you get the full details of Fyr-Fyter’s amazing plan. The Fyr-Fyter sales force is one of the highest paid sales organizations in the world. Probably more men are making $5,000 a year—or more— with Fyr-Fyter than with any other direct selling company on earth. Don’t miss this life-time rp Grasp it today. Simply mail the coupon. FYR-FYTER CO. Devices Approved by Underwriters’ Laboratories 1386 Fyr-Fyter Bldg., DAYTON, O. r- s Fyr-Fyter Co., 1386 Fyr-Fyter Bidg., Dayton, Ohio Send me free and without obligation your book, “Building a Permanent Income,”’ and full details of your plan. SSSCCESSSCSSERSSSSESSSSSSEese

Page 150

I need YOU with 100 firms BEGGING ME to send them more DRAFTSMEN. Many offer to take BEGINNERS, at $50 a WEEK. Many Graduates start at $90 and $100! GET BUSY! Drafting is the BIG field, men. Every in- dustry you can name BEGINS with the draftsman. Without mechanical drawings —by the thousands—every shop in the land would be STOPPED. In fact, it is the SERIOUS SHORTAGE of draftsmen that brings this offer: J will JSurnish all instruments, - fe even to the table, to those who start now PAY AS YOU GO Po"_sive me the ex- cuse that you have no ready money for this golden opportunity. I am not so interested in cash; I want your application. I want at least 200 men to start right now. I want them ready to recommend by Spring! We will get a flood of letters saying “‘send us draftsmen,”’ from every sort of industrial and engineering concern, and we must make good. The first week’s pay envelope of many a Dobe-trained draftsman has held enough to cover the entire cost of the course! Most students learn evenings, keeping on with their old work until ready to step into some- body’s- drafting room. ‘ The first. month equips you to e on simple drafting jobs on the side. It helps you learn; I gladly permit this. Well-Paid Positions Every Way You Turn A draftsman soon forgets the days when he used to wonder where to get a job. In- stead, he asks “‘What line of work interests me most?’’ And “‘What part of the country suits me best?’’ Twenty of my graduates went to Florida this year; three are in Japan; last month one wrote me from lon. And I wish we had the count of how many Dobe draftsmen have become chiefs! _ Positions loom up almost as soon as you are enrolled in a Dobe class! We receive requests daily for junior men—for men only ‘partly through our course. “‘We’ll take a beginner,’’ some concerns write us, “‘so long as he is a Dobe-trained man and has begun right!”’ IT’S EASY and interesting to learn ‘ : drafting. For drafting isn’t “drawing!’? You don’t need any “talent.”’ A draftsman uses fools for every line and every curve. You couldn’t make them crooked if you tried! That’s why drafting is so easily learned—and so inter- esting. For you do everything by rule. So, I guarantee to make anyone a finished drafts- man; if you can read and write, you can learn this line. One of my students is 51 years old; another is just seventeen. But they’ il all be making @ grown-up salary by Spring! WARNING! The special offer of * tools is for immediate action. Don’t expect me to hold it open indefinitely. Clip the coupon zow for free CHIEF DRAFTSMAN \)OBE, Div., 13 1951 Lawrence Avenue Chicago - Special Tool Offer Send me FREE and POST PAID Successful ts. Draf manship Book and -material telling all about your home course, terms, etc. 69 => Name Age Address The New Wonders of the Sea (Continued from page 151) Multiply that by 150 and you get 40,662,000, which was the total haul in that one small net. Plankton is commonly called ‘‘whale food’’ and many fishes eat it. Human beings could live on it if they had to. It is rich in nourishment. The whole human race may some day have to depend upon it, for the fish supply is decreasing, the price is going up, and the lack may have to be filled from the un- tapped larder of the sea. When we say “sea food”’ we think of fish and lobsters, oysters and crabs. The prices of these are going up, but there is an endless supply of other sea food. French scientists have investigated and say that all races can eat seaweed with profit, as Chinese and Japanese do already. It is as nourishing as carrots, beets, tur- nips and parsnips. _ All clams, cockles, scallops and even barnacles are edible. A giant barnacle, balanus evemanni, that abounds on our Pacific coast, has a delicious flavor and the same food value as lobsters, prawns and crabs. Even the dread octopus can be, and is, eaten in Eastern Asia. The sea cucumbers—they are animals—which we do not eat, sell in Hongkong at $700 a ton. HEN McGinty got to the bottom of the sea, he found magnificent scen- ery unparalleled on land. In the tropics, with coral, sponge and colored shells and plants, the vista is brilliantly colored and of luxurious and fantastic outlines. The sea floor is of rock, covered with sediment from rivers. Then comes matter derived from fragments of marine plants and animals, shells, skeletons, bones and coral fragments. Sometimes there are meadows filled with sponges and sea plants. Many so-called marine “plants” are animals, and sinister animals, too. The sea anemones, roses and pinks are, in fact, pirates lying in wait for victims to devour and sate appetites that, like those of most sea animals, are voracious. Anemones are really highly colored animals with tiny myriad tentacles and warts that look like flowers but are far from it. How deep is the sea? There are fifty de- pressions or “deeps” known to science, varying from 3,000 to 5,000 fathoms. The greatest is forty miles east of northern Mindanao, in the Philippines, and its depth is 5,348 fathoms, or 406 feet more than six miles. This depth exceeds by 3,000 feet the height of the loftiest moun- tain peak. The average depth of the ocean is probably not less than 2200 fathoms, about two miles. HOSE are only some of the wonders of the sea. Many more are unknown as yet, for oceanography is practically a new science that has developed mostly in the past thirty years. There are many im- portant problems still awaiting solution. “Yes, there are more wonders,” Dr. Townsend will tell you with a twinkle in his eye. ‘‘There is the planked shad, for instance, and the planked whitefish. Did ou ever see one walk the plank? **What did you ask? Sea serpents? Tell it to the Marines!” MONEY, MAKING OPPORTUNITIES SECTION December, 19% “Genius ite self must learn the ma- chinery of expression.” “Since authorship is essentially a mat of home work,” says Rupert Hughes, ith one of the few arts that can be taught by correspondence: The Palmer Institute of Authorship, under the presidency of so eminent a literary artist as Clayton. Hamil- ton, and as conducted by Frederick Palmer and a large corps of associates, is qualified to render invaluable aid to apprentices in the art and the business of authorship,” » » » Palmer training is uniquely personal. It will take that talent of yours and develop it until you, too, can write the kind of Stories that tug at heart strings . . . that grip the imagination . . . that editors buy, PALMER INSTITUTE OF AUTHORSHIP Palmer Building, Hollywood, Cal. 124-M CLAYTON HAMILTON = = = President FREDERICK PALMER = = Vice-president Please send me, without obligation or expense, 4nformation about your course in 0 Short Story Writing LJ English and Self-Expression (Each course is complete in itself.) Name II oo os5 9550002: crssecnsagveseasesinssocseeovstonegsezesumane All correspondence is strictly confidential, No salesman will call on you. AC “THE CONTROL OF BUSINESS Accountants command. big income. Thousandsneeded. About9,000 Cer- /f tified Public Accountants in U.S. Many earn $5,000 to $20,000. We train you thoroly at home jn your spare time for C. P. A. examina- tions or executive acccunting positions. Previous bookkeep- ing know!edge unnecessary— we oy" you f a ground up. Our training is super- vised by Wm. B. Castenholz, A. M., This Book C. P. A., assisted by staff of C. P. A.’s. Low cost—easy terms. Write FREE! now for valuable 64 page book free. LaSalle Extension University, Dept. 3283-H Chicago —m"~ ANY BOOK IN PRINT ivered at your door. We the gente pense rae ions, 8, all at bigg sea Be t to send postcard for log. for our great book cat. alog. This catalog is a short course in Bpeeptare pnd is so = pee et ee 800,000 DAVID B. CLARKSON Take up poultry raising. It’s interesting, health- ful and very, very PROFITABLE. Easy to sell all you can peodace—-at big prices. Our new, up-to-the-minute course prepared by H. M. Lamon, former gov't expert, gives all short cuts to success. ousands eet big money with our methods. Free book, ‘‘How to Raise Poultry for Profit,’’ will open your eyes. Write for a copy today. NATIONAL POULTRY INSTITUTE Dept. 413 Washington, D. C. Many earn $3,000 to $10,000 a year. Prepare quickly durin . eo earn while ou learn Rew Ses Shot pare time. y ° % ating. sts like it. Send at once for free book, ‘‘Opportuni- ties in jodern Photography’’ and full particulars. Special offer open now. NTERNATIONAL STUDIOS, Inc. Dept. 1369, 3601 Michigan Ave., Chicago, U.S.A. See New Financial Department on Page 4—Front Section. THE BOOK ° BROKER | 1220 GLARKSON BUILDING, CHICAGO, ILL | . Results Quick—Part or Full Time ‘

Page 151

= — ~ YEIRB «e STS. Gee | S386? o Ee | F MWRFRSAT AT Te December, 1926 Ways We Use Waste (Continued from page 27) is burned are recovered for use. Fully as astonishing are the new fuels ob- tained from things which ‘once were considered to have no practical value. In [llinois, for instance, engineers recently proposed a plan to salvage the gas J ‘ wasted in the treatment of city sewagey and to employ it for household heating urposes. This gas, they say, is odorless when burned, and has high heating value. In a city of 50,000 persons, they estimate fully 90,000 cubic feet of gas can be ob- tained in this way. NOTHER surprising development is a A newly discovered method of obtaining high-grade fuel, resembling fuel oil, from jow-grade “backstrap” molasses, which until now has been ‘considered a waste product of sugar refineries. This strange sweet fuel does double duty; for the resi- due, after burning, can be converted into tash and used for fertilizer. The proc- ess is the invention of Dr. Paul G. Hilde- brandt, chemical and mechanical engineer of Swarthmore College, Pa. In the labora- tory he has demonstrated that the fuel obtained from each ton of low-grade molasses has a heating value equal to a ton of coal, and produces 150 pounds of commercial potash besides. He estimates that the salvaging of waste molasses in some 5,000 raw sugar factories in the world will represent a yearly saving of $22,000,000. The rapid depletion of our forests has called the attention of scientists to the extravagant waste that goes on in the lumber industry. At least seventy-five percent of every standing tree is wasted, on the average, when it is converted into lumber. This loss is represented in the limbs, stumps, knots and tops of trees, as well as in sawdust and mill shavings. A few weeks ago Jacque C. Morrell, of Riverside, Ill., and Dr. Gustav Egloff, of Chicago, told the American Chemical Society that they had succeeded in re- ducing the wastes from Douglas fir into tar. By the chemical process of “crack- ing,” such as is used in making gasoline from crude oil, they split the wood tar up into light volatile oils suitable for motor fuels, solvents, and paint thinners. LMOST at the same time a bulletin issued by the New York State College of Forestry, Syracuse University, an- nounced experiments showing that waste products of the forest offer a great source of human food. Animals thrive on the leaves, branches, tender twigs, and some- times the bark of trees; why not men? The Rocky Mountain yellow pine, when examined recently, was found to contain 8.19 percent protein, the food property so important to man. This is nearly as much as the protein content of wheat, which is 12.4 percent, and of field corn, which is 10.1 percent. Before we realize it, choice dishes from twigs and leaves may be a regular part of our bill of fare. Sucha possibility, however, isno stranger than are some of the articles of food, medicines and drugs now produced from things considered worthless. The blood of animals in the (Continued on page 154) MONEY MAKING OPPORTUNITIES SECTION LAW OFFICES Vda RIL 2 U-S- PATENT Strict Secrecy Pre- served—Write Me in Confidence All communications, sketches, drawings, etc., are held in strictest confidence in strong, steel, fireproof files, which are accessible only to authorized members of my staff. Feel free to write me fully and frankly. Your case will have my personal attention. It is probable that I can help you. Highest references. But FIRST— clip the coupon and get my free book. Do THAT right now. and the “Record of Invention’ form, together with detailed information on how to proceed and the costs involved. Do this NOW. No need to lose a minute’s time. The coupon will bring you complete information entirely without charge or obligation. Clarence A. O’Brien Registered Patent Attorney Member of Bar of: Supreme Court of the United States; Court of ——— District of Columbia; Supreme urt, District of Columbia; nited States Court of Claims. Practice confined exclusively to Patents, Trademarks, and Copyrights Protect Your Ideas Take the First Step Today If you have a useful, practical, novel idea for any new article or E for an improvement on an old one, you should communicate with ——=__ a competent Registered Patent Attorney AT ONCE. Every year thousands of applications for patents are filed in the U. S. Patent ce Office. Frequently two or more applications are made for the same or substantially the same idea (even though the inventors may live in different sections of the country and be entirely unknown to one another). In such a case, the burden of proof rests upon the last application filed. Delays of even a few days in filing the application sometimes mean the loss of a patent. So lose no time. Get in touch with me at once by mailing the coupon below. No Charge for Information on How to Proceed The booklet shown here contains valuable information relating to patent procedure that every inventor should have. And with it I will also send you my “Record form, on which you can sketch your idea and establish its date before a witness. Such evi- dence may later prove valuable to you. Simply mail the coupon and I will send you the booklet Mail thisCouponjnow! NVENTORS YW vt Write for these “FREE BOOKS/ » At the left is a view of my drafting and _ specification offices where a large staff of experienced experts is in my constant. employ. All drawings and specifications are prepared under my per- sonal super- vision. Prompt—Careful Efficient Service = This large, experienced organization devotes its entire time and attention to patent and trademark cases. Our offices are directly across the street from the U. S. Patent Office. We understand the technicalities of patent law. We know the rules and re- quitements of the Patent Office. We can proceed in the quickest, safest and best ways in preparing an application for a patent covering your idea. Our success has been built on the strength of careful, efficient, satisfactory service to inventors and trade- a owners located in every state in the nion. of Invention” e J®*®eeeeeeeseees Clarence A. O’Brien Registered Patent Attorney 88-H Security Savings & Com. B 3 Washington, D. C. . sahara Please send me your free book, ‘“‘How to Obtain a Patent,” and your “Record of Invention” form without any cost or obligation on my part. (Important: Print or Write name clearly) pecan

Page 152

154 MONEY MAKING OPPORTUNITIES SECTION | December, ma" ee PATENTS TRADE-MARKS DESIGNS FOREIGN PATENTS MUNN @ CO. PATENT ATTORNEYS Associated since 1846 with the Scientific American 1583 SCIENTIFIC AMERICAN BLDG. 24 W. goth St., New York City 1311 TOWER BUILDING Chicago, Ili. 519 VAN NUYS BUILDING Los Angeles, Cal. Untrep States CaPirou PATENTS DON’T LOSE YOUR RIGHTS TO PATENT PROTECTION Before disclosing your invention to anyone send for blank form “EVIDENCE OF CON- CEPTION” to be signed and witnessed. As registered patent attorneys we represent hundreds of inventors all over the United States and Canada in the advancement of in- ventions. The form “Evidence of Conception,” sample, instructions relating to. obtaining of patents and schedule of fees sent upon request, LANCASTER & ALLWINE 274 Ouray Building WASHINGTON, D. C. Originators of forms “Evidence of Conception.” a Books and Information on Patents and Trade Marks By Request. Associates in All Foreign Countries. 522 SCIENTIFIC AMERICAN BLDG. Washington, D. C. 664 HOBART BUILDING San Francisco, Cal. GETTING AHEAD? Read the advertisements on Pages 134 to 165 this issue if you want to get ahead. To the Man With an Idea I offer a most comprehensive, experi- enced, efficient service for his prompt, legal protection and the development of his proposition. Send sketch, or model and description. for advice as to cost, search through prior United States patents, etc. Preliminary advice glad- ly furnished without charge. My experience and familiarity with various arts, frequently enable me to accurately ad- vise clients as to probable patentability be- fore they go to any expense. Booklet of valuable information and form for properly disclosing your idea, free on re- quest. Write today. RICHARD B. OWEN Patent Lawyer 6 Owen Building, Washihgton, D. C. 41-D, Park Row New York City TRADE -MARKS REGISTERED our terms, methods, etc. Send of your invention for Inspec- tion and Instructions Free. Terms Reasonable. Best Ref- erences. RANDOLPH & CO. Dept.130, Washington, D.C. NVENTORS your iweas Send for our Guide Book, HOW TO GET YOUR PATENT, and Evidence of Invention Blank, sent Free on request. PROTECT Tells model or sketch and description (NR deel i 5 ES ery ere en Ways We Use Wass (Continued from page 153) big slaughter houses, for example, alway, has been thrown away. Now chemists have found a way of removing the hem. oglobin, which gives the blood its req color, and using the residue to make meringues in place of whites of eggs, From fish refuse, Professor Nils Hanssen, a former head of Sweden's department of agriculture, has produced a flour which he declares is an excellent food for cows and pigs. At Gothenburg the largest fishing center of Sweden, ail refuse now is saved and shipped to a factory where it is converted into the flour and sold to farmers for fattening their live stock. The screenings are used for chicken feed. VEN old shoes have their value. At Tufts College, Medford, Mass., a young magician of science has succeeded in converting scrap leather into valuable drugs, medicines and perfumes. From sea- weed, too, Dr. J. W. Turrentine of the U. S. Bureau of Soils has extracted iodine which has been found effective in the treatment of simple goiter. The nation’s junk piles of metal no longer are being allowed to go to rust and decay. Last year 800,000 tons of metal from the scrap of factories and junk deal- ers were recovered and turned back to use—a saving of some $200,000,000. Of the million automobiles which wear out every year and are cast aside, all but a small proportion now are salvaged. Perhaps the most remarkable example of how modern industry is learning to make use of scraps is found in the salvag- ing plant which Henry Ford has es- tablished at Highland Park, near Detroit. Here 500 men are employed to turn every bit of waste to some useful end whether it be a bit of rope, an old bag, or a piece of paper. Whena Ford mechanic wears outa pair of rubber boots they may be turned back into rubber tires. Old leather from shoes or aprons and scraps of new leather are turned into washers, hand pads, gaskets and leather molds used for various types of machines. Old rubber gloves are cut up for finger protectors. Rope, bags and burlap are shredded and put into cushions. Through this endless process of salvage, Ford savessomethinglikeeighteen million dollars a year. HEN Thomas A. Edison was asked some time ago whether he planned to produce any new inventions in the near future he replied: “* No, I think it would be better for the world if it waited awhile until it learns how to use the inventions it already has.” He meant to tell us that we are pro- fligate of the wonderful heritage left to us by the creators and discoverers; that we can find unsuspected value in the last scrap, if we will stop a moment in our mad pace and look for it. House F.ies have decreased noticeably in number since automobiles came, says a Providence, R. I., health official, be- cause there are now fewer horse stables, principal breeding places of flies. ee ee a, oes Ohi Pe

Page 153

er, ne" ie —, December, 1926 MONEY MAKING OPPORTUNITIES SECTION fjunney Tells How He Won the Championship Mi (Continued from page 29) hem. aa , Ted the fight. Fighting fire with fire, as it nake were, smiled Gene. : “Have you ever stumbled over any- Nils thing in the dark?” he asked me sudden- len’s ly. “It’s about as disturbing an. experi- uced ence as you can have. That s because llent you’re not ready for it, and it was by urg injecting that same element of unex- , all pectedness into my first punch that I io % planned to beat Jack Dempsey. a « aNY old punch wouldn’t do, though. ised A It had to be a punch that would be sure to land—and one that carried the knockout shock. Study of Jack Dempsey’s At tactics as he rushed from his corner— motion pictures of his fights were avail- » & ° ded able, you know—soon convinced me that able a straight right-hander, timed to the Sea. instant and delivered with all the beef the and spirit I possessed, was the ticket, so ted I began practicing that punch. I prac- e in ticed it against punching bags, with sparring partners; I bombarded the no empty air with it in shadow boxing. I and even let it loose at odd moments—as stal when I was waiting for my turn to tee up ~al- a golf ball. I went through the motions to of delivering it on moving picture sets. 00. Months ago I had it worked out to the ear utmost perfection of timing and accu- nut racy. And that punch,” said Gene Tunney impressively, “won the fight for ple ae ; ; te _ “It wasn’t - delivered exactly as [ 1g- had planned. I couldn’t land it in ey Dempsey’s first rush. But in his second ‘it rush, out went my right—bang!—the : hardest punch I had ever delivered. Tr , ‘ i Jimmy Bronson, my chief second, who of knew all about the punch, of course, had te told me before the fight, ‘Land that ed right-hander! Break your arm, if you must, but land it!’ I landed it all right, 2 but I missed. It was aimed for the point Is of Dempsey’s jaw, but it struck him on ad the cheekbone. It didn’t knock him out, "= but the force behind it was so great and Bs the timing so exact that he never re- to covered from that blow. It stunned him of : physically, and surprised and discon- certed him mentally, so that, as he him- self said after the fight, he never got started. ; “QUPPOSE it had not had that stun- tu: ning effect?” I asked. “TI’d have been in for a tough time,” e mn : “yy? a responded Tunney simply. “I’d have t taken many more terrific punches than the few Dempsey managed to land. ; However, I was prepared for that, too. I had made certain that I could weather . a storm of heavy punches by taking ‘ plenty of them on my face and body while I was training. My sparring partners : wore football headguards in training. I didn’t. I was training to take punish- ment as well as to avoid and inflict it. y “All the practicing and all the training $ in the world, of course, would not have ’ assured that decisive blow if I hadn’t had , absolute confidence that I was capable of : _ | doing the job. I had to be so absolutely sure of myself. (Continued on page 156) ENT TRADE:MARKS | COPYRIGHTS# OUR OFFER: Your first step—Before disclosing an inven- tion the inventor should write for our blank form “RECORD OF INVENTION.” This should be signed, witnessed and returned to us together with model or sketch and description of the invention for INSPECTION and INSTRUCTIONS. NO CHARGE FOR THE ABOVE INFORMATION Our Four Books Mailed Free to Inventors Our Illustrated Guide Book HOW TO OBTAIN A PATENT Contains full instructions regarding U. S. Patents. Our Methods, Terms, and 100 Mechanical Move- ments illustrated and described. OUR TRADE-MARK BOOK Shows value and necessity of Trade-Mark Protec- tion. Information regarding T'rade-Marks and unfair competition in trade. OUR FOREIGN BOOK We have Direct Agencies in Foreign Countries, and secure Foreign Patents in shortest time and at lowest cost. Progress of Invention Description of World’s Most Pressing Prob- lems by Leading Scientists and Inventors ALL COMMUNICATIONS AND DATA STRICTLY CONFIDENTIAL INTERFERENCE AND INFRINGEMENT SUITS PROSECUTED IMPORTANT TO MAKE YOUR CASE SPECIAL AND AVOID DELAY YOU SHOULD HAVE YOUR CASE MADE SPECIAL IN OUR OFFICE to secure protection, save correspondence and obtain early filing date in Patent Office. To secure special preparation of your case send $25.00 on account with model or sketch and description of your invention. Private Office, Victor J. Evans, with View of Patent Office Through Window Reasonable Terms Pittsburgh Offices 514 Empire Bldg. sco Offices, Hobart Bldg. Highest References Prompt Attention FREE VICTOR J. EVANS & CO., Patent Attorneys Main Offices: 760-9th St., N. W., Washington, D. C. Coupon New York Offices Philadelphia Offices 1007 Woolworth Bldg. 518-19 Liberty Bldg. Chicago Offices, 1114 Tacoma Bldg. San Francis Gentlemen: Please send me FREE OF CHARGE your books as described above. DN MUOS IN oe vivid Selb as Ghn 4 a8 ae oD ouats ontredas Val sed eee eoe aes scagemeoese’ PUB oso is aca hg caine su's cies 30024 cud 4 debs CepIMORUAENE © bed ne eusememaeiaiua age teks eT ec tee ete (eUeseeeeeeeeensasasesrsesssd

Page 154

SHOW CARD LETTERING learn at Home _s is the very course you need if you want to a good paying position as a Show Card Letterer gh Letterer, or have a business of your own. This course is complete and practical and especially atranged to meet the needs of the student who studies at home. It was written by E. L. Koller, Principal of the School of Art of the International ‘Correspon- dence TE member of the American Federation Arts, and The. National Society of Craftsmen. Mr. Koller has had twenty years’ teaching experi- ence, and his success in helping other men and women is 4 nag of what he can do for you. Wood, a clerk, made more than $700 “on Fh “ide” before he had completed his course and also won $125 in prizes. Harry William Lord writes that he has more than doubled his salary as a result of studyin — 3 this I. C. S. course in spare time. William itman, a former wagon builder, now has a ~ 3 painting business of his own is earning nearly three times as much as he did before enrolling with ha International Correspondence Schools. There is no doubt that Show Card Lettering and Sign Lettering offer a real spoeteniy te to ambitious men and women. Just mark and mail the coupon and we'll gladly send you a booklet telling all about the I. C. S. course in Show Card Lettering, or any other subject in which you are interested. INTERNATIONAL CORRESPONDENCE SCHOOLS Box 7616-E Seranton, Penna. The oldest and largest correspondence schools in the world Without cost or obligation on my part, please tcll me how I can qualify for the position or in the subject before which I have marked an X: OO SHOW CARD LETTERING O ILLUSTRATING 0 CARTOONING Business on Advertising Business Better Letters Banking ona) Banking Law Stenography and Typing Accountancy (including C. P.A.)LIBusiness English Lid Sh Nicholson Cost Accounting Civil Service _.] Bookkeeping Railway Mail Clerk Private Secretary ommon School Subjects E)Salesmanship High School Subjects TECHNICAL AND INDUSTRIAL COURSES Electrical Engineering Surveying and Mapping Electric Lighting Architect }Mechanical Engineer Architect’s Blueprints eg Draftsman (Contractor and Builder Machine Shop — Architectural Draftsman Railroad Position: Structural Engineer Gas Engine Operating hemistry (] Pharmacy Civil Engineer Automobiles Steam Engineering D) Radio [Mathematics Name Street Address...... City State. Don’t Envy The Plumber BE ONE! $41.00-$16.00 PER DAY and work EVERY day, is the Plumber's wage. * Brery skilled workman will tell you that Plumbers have the of it. WINTER and SUMMER the Plumber is busy at wages. No skilled Plumber is ever out of a job--compare his opportunities _ any trade, plus the opportunities of having your own shop. We tench you Plombing with TOOLS (not books) Licensed Master P RS in one of the finest e schools 4 America. We make you a Plumber, every 4 is t poroeghiy--Laad Work--Blue Print ‘for plan read- ing--all other trick: LEARN IN 8 to 12 WEEKS ~~ weit are making sone, than $60.00 eek you owe itt to your- f to a stigate. Get FREE catalog that tells in pictures words how we teach this trade. Special rates now. UNIVERSAL PLUMBING : SCHOOL 2031 Troost Ave. SAS CITY, MO. MONEY MAKING OPPORTUNITIES SECTION Tunney Tells How He Won the Championship (Continued from page 155) “That’s all there is to the trick of becoming heavyweight champion. of the world—or anything else that you might aspire to and that lies within your capabilities. If you can convince your- self— honestly—that you can do a thing, you can do it. “T do believe that anyone, who, after studying his capabilities and talents, is confident that he can become a great artist, singer, inventor, business leader, politician or whatnot, can achieve his ambition. You know quickly whether you’re on the right road, for the hardest person in the world to deceive is yourself.” ’VE interviewed scores of famous athletes on the same subject on which I talked with Gene Tunney for PopuLar ScrenceE Montuiy—themselves, and the “how” of their achievements. Tunney, though, is the first who has given me a satisfactory answer. He knows how he fights, because he fights not with a body directed by native instinct and a mechan- ical skill acquired by practice, but with his brains. He has been criticised for being a “made” fighter, for lacking the “killer instinct”’ that all great performers of the ring are supposed to possess. I sub- scribe to both these criticisms and my hat is off to him in consequence! He’s not only a “made” fighter, but a self-made one, and a corking good job he’s done of it, too! That he lacks the wolfish ferocity that causes some pugilists to glory in pounding an already beaten opponent into helplessness, in my opinion, re- dounds to his everlasting credit, for he has won the greatest prize in the gift of the ring without it. His poise, his self-control, his self-con- fidence and his courage are admirable. MAGINE a man, who, thirty-six hours before the greatest crisis in his life, spends two hours in utter absorption in the task of teaching the elements of golf to a friend who didn’t know a niblick from a sand trap! Imagine a man, who follows that session on the links by going to his room, sinking his head into a book, reading for an hour or more in utter detachment from the world about him! Imagine a man, who, keeping an engagement which means fame, fortune and the achievement of his life’s ambi- tions, makes his way to the place, over the protests of his well-wishers, in an airplane—the first time he had ever entered one! Imagine a man, who, dressed in his ring clothes and about to fight for the heavyweight championship of the world, spends the five minutes immediately preceding his entrance to the ring peace- fully sleeping in his dressing room! I saw Gene Tunney do all these things. And so I do not hesitate to call him, as I did at the beginning of this article, the most remarkable young man who ever entered the prize ring, and a young man whose influence as heavyweight cham- pion is bound to reach far beyond the world of sport. EARN UP T | Per Month — Md = Unusual opportunities in this ne Travel; meet ine railway officials. Prepamtions in 3 months’ spare-time home study. eaey START AT $120 PER MONTH. Expenses Paig Upon graduation we secure position for or refund your money. More men needed? ™™ __ Mail coupon on today, Send me, entirely No. D-708, givin; if » Booklet about course ine fal Pirie Inspection. HEAVEN and HELL By Emanuel Swedenborg This book of 632 pages, or any of the following works of Swedenborg, printed in large type on good paper, well bound in stiff paper covers, will be sent prepaid on receipt of 5 cents per book: Divine Providence....................... 6 Treats of the government of the universe and of the human soul by the love and wisdom of God, emphasising the fundamental need of freedom in the life of man. Divine Love and Wisdom............... 618pp. Shows that the Divine Love is the fountain from which all things proceed; gives also a philosophic outline of the primary processes of creation. Beaver: ana FIG.......... 2.05050. .ese0ed 632pp. An epoch marking revelation of the conditions that prevail in the spiritual world and of the laws under which each man finds his immortal abode. THE AMERICAN SWEDENBORG PRINTING AND PUBLISHING SOCIETY Room 810 16 E. 41st Street, New York PATENTS BOOKLET aan Bp PROMPTNESS ASSURED ESULTS Send drawing or model for ‘ntneaal and report as to patentability WATSON E. COLEMAN, Patent Lawyer 724 9th Street N.W., Washington, D. C. PATENTS Trade-marks, Copyrights, Patent Litigation, Handbook with illustrations, 100 mechanical movements. Sent free on request. ALBERT E. DIETERICH Formerly member Examining Corp. U. S. Patent Office Patent Lawyer and solicitor 27 years’ experience 681-A Ouray Bldg. Washington, D.C. aoe inventors at lowest PATENTS freee —_ — ee perv oe a by many well knows ‘atents of extraordinary value. Book, Patent-Sense, Lacey& Lacey, 648 F St., Wash., | D.C, Estab.1i ple i mmercialized ON A CASH OR ROVALTY BASIS A -— of so oldest pat- firms in America we ‘n Business 2S eg Complete Facilities-References. Ure ADAM FISHER MF. Co.. 183-D Enright Ave. St. Louis.Mo. Advice for POPULAR SCIENCE MONTHLY readers regarding safe and profitable investments. See Page 4 ee ee a

Page 155

4 ‘ion, ical D fice SF Se —- pecember, 1926 Ms Your House Heated S. Properly? (Continued from page 32) dight argument between the one-pipe circuit and the one-pipe relief layouts. Automatic air valves above the steam mains improve the system. Steam supply mains should slope away from the poiler at the rate of one inch to ten feet, while the return pipes which carry water ‘of condensation must pitch back at least at the same rate to the boiler. : “Pipes that sag or lack the proper uniform pitch cause those unholy gurgles and knocks that some people regard-as the inevitable music of a steam plant. A defective air valve at the radiator may also cause the tumult. Sometimes a cor- rect air valve is fussed out of order. Ad- just it once and then leave it alone.” “COME of our friends who have hot water systems recommend them highly,” observed Ellen. “Every Arab praises his own camel, according to the proverb, but in this case your friends are quite within reason. About the only drawback to hot water is the too slim purse of the prospective owner who can’t afford long-run economy. Water retains heat and emits it steadily, tending to keep the house temperature more uniform than do other methods. There is no noise, no valve fixing, no pressure question. The same water is used indefinitely, but for that matter a steam boiler requires only a trifling re- plenishment of water during the season.” “Do we figure hot water size the same as steam?” asked Rob. “Use the same rule but add sixty-five percent for extra radiation surface needed to compensate for the relatively low temperature of hot water, usually around 180 degrees. This is like vapor compared with steam, only more so. In the example of the steam-heated room we discussed, 461% ft. of radiation was required. For hot water, adding sixty- five percent, we raise the requirement to 7634 sq. ft. “TO GET the boiler size, take the total of room needs, add one third for pip- ing (instead of one quarter as in steam, be- cause there are more pipes) and seventy- five percent for safety margin. Hot water requires double piping—you notice that a radiator has top and bottom connec- tions—also it calls for an expansion tank in the attic. An altitude gage at the boiler tells whether there is enough water in the expansion tank, saving stey)s to the attic for inspection.” “*How does hot water cost compare with steam?” inquired the young man. ““Well, we have already seen that the material for the first is more than half as much again than steam of the ordinary type. Labor for hot water installation is estimated at two and one half to three days for man and helper per radiator; while steam, single pipe circuit, takes but one and one fourth days for man and helper per radiator. While these work estimates are given by an authority, I have seen a small installation of steam done in half the time allowed.” Over $10,000 a Year C. V. Champion of Mlinois $1,000 in 30 Days W. Hartle spent ten lean years counts it a ‘‘red letter day’’ in the railway mail service be- when he first read this remark- fore ‘‘Modern Salesmanship’’ able book _ ern Sales- pat him on the road to big pay. manship. He says ‘‘It en- e has earned more in a wee! than he formerly earned in a month—averaged over $1,000 for thirty days! abled me to learn more, earn more, and BE MORE!”’ To-day his earnings exceed $10,000 a MONEY MAKING OPPORTUNITIES SECTION 157 ee $13,500 First Year A. H. Ward was formerly a Chicago clerk, earning $25 a eek ithi $7,286 Last Year F. G. Walsh was a clerk earn- ing $1,000 a year, ond, trying week. Within one year he in- to_ support a wife and three creased his earnings $13,500 children, N.S. T. A. training a year! The book—‘‘Modern built up his income last year to Salesmanship’’ — proved the 286 — a of over first rung in the ladder to Suc- 00 per cent. cess! ~and They Started By Reading This Amazing Book! _ Now—For a Limited Time Only—This Remarkable Man- oa ‘ ena 5 Oe Building, Salary-Raising Volume is Offered FREE to ie ; Every Ambitious Man! If You Ever Aspire to Earn j $10,000 a Year or More, Read It Without Fail. Where Shall We Send Your Copy FREE? BOOK. Just seven ounces of paper and printers’ ink—but it contains the most vivid and inspiring message any ambitious man can ever read. It reveals the facts and secrets that have led hundreds of ambitious men to the success beyond their fondest expectations. So powerful and far reach- ing has been the influence of this little book, that it is no wonder a famous busi- ness genius has called it “The Most Amaz- ing Book Ever Printed.” This vital book—‘‘Modern Salesmanship’’— contains hundreds of surprising and little-known facts about the highest paid profession in the world. It reveals the real truth about the art of selling. It blasts dozens of old theories, explains the science of selling in simple terms, and tells exactly how the great sales records of nationally- known star salesmen are achieved. And not only that—it outlines a simple plan that will enable almost any man to master scientific salesmanship without spending years on the road—without losing a day or dollar from his present position. What This Astonishing Book Has Done! The achievements of this remarkable book have already won world-wide recognition. The men who have increased their earning capacities as a direct result of reading ‘‘Modern Salesmanship” are numbered in the thousands. For example, E. E. Williams of California was struggling along in a minor position at a small salary. ‘“‘Modern Sales- manship”’ opened his eyes to things he had never dreamed of. Within a few short months, he was earning $10,000 a year! Today he receives as much in 30 days as he used to receive in 365! J. H. Cash of Atlanta. He, too, read ‘‘Modern Salesmanship” and found the answer within its pages. He quickly raised his salary from $75 to $500 a month! W. D. Clenny of Kansas City commenced making as high as $850a month. F. M. Harris, a former telegrapher, became sales manager at $6,000 a year. O. H. Mal- froot of Massachusetts became sales manager of his firm at a yearly income of over $10,000 a year! A Few Weeks—Then Bigeer Pay There was nothing “different” about these men when they started. Any man of average intelligence can duplicate the success they have achieved—for their experience proves that salesmen are made—not born, as some people have foolishly believed. Salesmanship is just like any other profession. It has cere tain fundamental rules and laws—laws that you can master as easily as you learned the alphabet. And through the National Demonstration Method—an exclusive feature of the N. 8. T. A. system of SALESMANSHIP training—you can acquire the equivalent of actual experience while studying. Hundreds of men who never sold goods in their lives credit a large por- tion of their success to this remarkable training. Free to Every.Man If we were asking several dollars a copy for “Modern Salesmanship” you might hesitate. But it is now FREE. I cannot urge you too strongly to take advantage of this oppor- tunity to see for yourself what salesmanship has done for others—and what the National Salesmen’s Training Associa- tion stands ready and willing to do for you. Find out exactly what the underlying principles of sal hip are—and how you can put them to work for you. No matter what your opinion is now, ‘‘Modern Salesmanship” will give you a new insight into this fascinating and highly-paid profession. Mail the coupon now! Dept. W15, N. S. T. A. Bldg., Chicago, Ill. F watio 1" Salesmen’s Training Assn., ——SSSSsSsS~S~S ik See eS Barend me rer rn ek : Name ...cccccccccccccccccccccecsccncceseccccsccccsecossoesesessoscssesees ‘ ' Address GRP... ccccccccececcccccccceoscsccscoses State.....cccccccccee Age ee ee Occupation Read interesting article on Page 4, ‘‘How $100 a Month, Invested Properly, Can Make You Independent.”’ 1 dents stand same chance. suffici nt—no political influence. | STE TRAVEL- for (UNCLE == RAILWAY MAIL CLERKS MAIL CARRIERS—POSTOFFICE CLERKS $1700 to $2700 a Year for Life No “‘lay-offs’’ because of strikes, poor business, etc.— = ’ , : FRANKLIN INSTITUTE sure pay—rapid advancement. ‘City and country resi- SRush to me, entirely free et cutee 2 page book with (1) A Common sens: education =u description of the position checked below; (2) Free Cut * ADY WORK (25, coupon and mail it 5 MEN—BOi'S 18 to 45 } Use Coupon Before You Lose It yt Steseesas SSCORRHSSHHSSSESR eee eeeeSaeeaseseaesae > COUPON De Re C-271, Rochester, N. Y. = ample coaching lessons. = (JRailway Mail Clerk ($1900 to $2700) CiPostoffice Clerk ($1700 to $2300) COCity Mail Carrier ($1700 to $2100) = CiCustoms Positions ($1140 to $1860) CJInternal Revenue ($1140 to $1860) es (Rural Mail Carrier ($2100 to $3300) ny

Page 156

} | | 158 Aviation! D® you love adventure? Do you want to make big money? Although aviation is still in its infancy thereis a crying demand for men with courage, nerve, MONEY MAKING OPPORTUNITIES SECTION | he says Benjamin Franklin, Experimenter (Continued from page 36) that “it was no small mortifica- tion to me, that I happened to be abroad (away from home) during two of the greatest thunderstorms we had early in the spring. I had given orders to my family that, if the bells rang when I was away, they should collect some of the lightning for me in electric phials, and they did so, yet it was mostly dissipated before my return.”” He was hot upon the trail of lightning. Picture this highly respected, somewhat rotund citizen upon the floor of his library, on hands and knees. Scattered about him —paper, twine, odds and ends of old silk rags from Mrs. Franklin’s scrap bag. ‘His Philadelphia friends were certainly justi- fied in raising their eyebrows. They knew him for an inventor, of course; but if he was perfectly sane, why should he | | be crawling about in his shirt sleeves with and self-reliance—ambitious men who are looking | for a new field. For those who qualify there will be | thousands of highly paid jobs. Amazing Opportunity in the Airplane Industry Yes, as yet, aviation is in its infancy, but nowis the time to get in. In the automobile industry and Fascinating — in the moving picture in business hundreds of men Daring ig got rich by getting in at Paying the start. They madetheir Prepare Now for One of success before others These Positions woke up, RACER TS TE Think how much avia- $60 to $150 per week tion has progressed in the Me i00 ts S300 eee last few years, Commer- Aeronautical oh neg cial air lines have already heropiane profits ee emeiees suc- to $75 perweek | cessful both in Europe Aergpiane Mecheniciar and America, Great men eens OX? teupecter redict that in the near to $75 per week uture there will be air- W38060 per year snd up freight lines — organiza- A , tions as large as our rail- Acroptane Builder roads are today. AVIAe $75 to$200perweek | TION IS NEW. It clamors for every young man, Be an Aviation Expert— $50 to $100 a week The stady of aviation is as fascinating as the actual work. Only one hour of spare time a day at home and we teach you the basic training. You will find ooery ee packed full of interest. Studen oy F. McNaughton, C lessons are like a romance, and what is more, after one reading the student gets a thorough understanding.’? Men who have had actual ay guide you carefully through your training. They select the lessons, lectures, blueprints, and bulletins. Once you start you can’t get enough of it. Here are some real jobs. Which one do you want? Aero- nautical Instructor, Aeronautical Engineer, Aeronauticad Contractor, Aeroplane poy rere go a oo : eroplane Mechanician, Aeroplane Inspector, Aero ane Assembler, plane Builder. : Big Aviation Book FREE titled.” Opportunition inthe Airplane induces itis ane niti n e ne indus ya a ictive. Get Sanibeheesadinieste ieee, AMERICAN SCHOOL OF AVIATION Dept. 1369. 3601 S. Michigan Ave., Chicago Se Se SS SBS SSE SSS SS eeeeeesenea”g sAMERICAN SCHOOL OF AVIATION 4 § Dept.1369. 3601 S. Michigan Ave., Chicago} t Without any obligation send me your free ae “Opportunities in the Airplane Industry,” also infor-g § mation about your Home Study Course in Practical i § Aeronautiés. & - 1 EE POC es adUo4 GW ir wnss Sacto toeceessveeeeeeet E b i] i Ly ' MGETESS. 000 ccccccccccvvccccscccccccccvccccccceses 7 t ‘ i MER PCa teen t's 5 s0secs easy PEE OS - 1 hicago, says, “‘Your- his mouth full of pins or tacks? Looking back upon all this now, you can get a glimpse of the youthfulness of Franklin. Who but a boy would think of sending up a kite to snatch a secret from heaven? KITE. As always, we can find no better words than his own, to de- | scribe just how he proposed to construct | and equip it. ‘Make a small cross of two light strips of cedar, the arms so long as to reach to the corners of a large thin silk handker- chief when extended; tie the corners of the handkerchief to the extremities of the cross, so you have the body of a kite, which being properly accommodated with a tail, loop and string, will rise in the air like those made of paper.” Anyone can follow him so far, and duplicate his construction—always re- membering that silk handkerchiefs, in his day of male finery, were larger than they usually are nowadays. A _bluejacket’s neckerchief might serve the purpose, if it did not prove too heavy, and Franklin takes care to explain why it should be silk. “This being of silk is fitter to bear the wet and wind of a thunder gust without tearing. “To the top of the satake stick,” he continues, “‘is to be fixed a very sharp pointed wire, rising a foot or more above the wood. To the end of the twine, next the hand, is to be tied a silk riband and, where the silk and twine join, a key may be fastened.” UNDREDS of times, in school read- ers, histories and other books, Franklin’s kite experiment has been de- scribed. But one point seems missing— —accurate data on weather conditions on the day of the experiment. Within very recent years kites have been flown by professional scientists just as artificial lightning of tremendous power has been manufactured in laboratories. Results show that it is possible, with a kite flying in clear weather, to get the effects credited to Franklin. But if he had flown his kite — (Continued on page 159) BEA TAXIDERMISS Learn at home bys mail to mount and stuff birds, animals, game-' —tee | furs be, skins and make fine Pugs Old reliable te school ~10, 00 . Sue- peckmens and pe ae = others. Ble demand ~ the work. Have a business of your uns, in spare. — ime for athletic ce traps. books and vacations, Kgreat opportunity. Grasp it. Write today, Repattes estratad book, jount Game.” Explains’ Fw pone of tax- of photos o mousped specimens. Tile how oa can learn ont one who fishes, oo or likes cotien lite | should ave this at book. Just send your mame and address. rite today. No obligation, Northwestern | Sevens of Taxidermy 1789 Elwood Build Omaha, Nebraska ‘508% 100 Weekly Selling Shirts Direct to Wearer, Mate by our Agents. No capital or perience needed. Spare or full time. Established 1885. Represent a real manufacturer. WRITE FOR FREE SAMPLES Madison Shirt Mnfrs., 562 Broadway, New York LEARN TENOR BANJO arn big m a Banjoists! Hewehit, "oney, thrash Coartes Ranjo Course. Simple as A B C—yet has all requirements: Includes = on Tec- + di ti —-) b ghords, played by Carles Meh fieNeh, 5 your care wit ones-B; ments. Send for Free = Chicago Tenor are institute 1621 WN. Lincoin Chicago, I, ogi a John V: . N. ts $25 for si sh card. Crawford, 8 goer Steet “Harned $300 “ad Dat delay. Sond today DETROIT SCHOOL O| or A ne Great Athletic Book oK'10¢ Be ce and gihletic. Leora wrestli fense, jiu eee rarmert Ae e. fret “s Got Champion, teach yo Great 0 ie ted for yor Hakes seo strong, hhealthy'and sxiiitex Sendi 6 e for ates by Burne and fiche ‘Only holds a few at this price. Write today. giving your age. ried a Farmer Barns School of Wrestling, 1789 Ramee, Bldg, Omaha, ny “y Pa —Write for my FREE BOOK. Ican Vise mena of ou at t home during spare ine; Write. ings tg BO ewtoneree a Good Pe’ It oan tains pI and ti "| System. Your name will be elegantly written ona 3 Ay —y of you enclose stamp to pay postage. Write to- ee CPA r book. ae, Fe W. TAMBLYN, 437 Ridge Bldg., Kansas City, U.S.A. Advice for Popular Science readers re- garding safe and profitable ments. See page 4. invest- hes others "mastered penmanship by the ainbige ‘ ie ek ee ee

Page 157

beet

Ss =" Eee. ee 8 eS Sle iat tit ie ioe oe Fae Minbari thes, 0S = 8 @ iF eo = =e (Seerres Bd ie oo SF

December, 1926

== Benjamin Franklin, _. Experimenter (Continued from page 158) in such weather, snatching down the jightning when there was none visible in the sky, surely he had far too good a sense of the dramatic to miss giving any- thingso startling the very widest publicity. On the other hand, suppose he had flown his kite in a real thunderstorm? A frightfully dangerous thing to do. We should then have had no Franklin to im- prove the Declaration of Independence; no Franklin to be a successful Minister to France. at Early biographers and historians knew little about electricity; they could not check up the scientific side of the experi- ment. And Franklin left behind no exact date, from which it might be possible to discover what the weather actually was on that memorable day. No one will ever know the exact conditions of the great test, but here is his description of the method and the result: *PEAHIS kite is to be raised when a ‘thunder gust appears to be coming on, and the person who holds the string must stand within a door or window or under some cover, so that the silk riband may not be wet; and care must be taken that the twine does not touch the frame of the door or window. As soon as any of the thunderclouds come over the kite, the pointed wire will draw the electric fire from them, and the kite, with all the twine, will be electrified and the loose fila- ments will stand out everywhere and be attracted by the approaching finger, and when the rain has wet the kite and twine so that it can conduct the electric fire freely, you will find it stream out plenti- fully from the key on the approach of your knuckle, and with this key the phial may be charged. “And from electric fire thus obtained spirits may be kindled and all other elec- tric experiments performed which are usually done by the help of a rubbed glass or tube, and thereby the sameness of the electric matter with that of lightning completely demonstrated.” Scientists now suggest that the current was induced, that is, created by influence across a space, not by actual contact. If the kite string had been wet enough to make a good conductor, bringing the cur- rent down to the key, it is hard to believe that the “loose filaments” of the string would “stand out everywhere.” But, ex- plain it as you please, the conclusion— that lightning and electricity are the same thing—cannot be denied. Most of us, in spite of the difficulty of understanding how he did it, leave Franklin with the credit for that discovery. IGHTNING takes many forms, often unnoticed because we are not as a tule enthusiastic about thunderstorms. ‘Zigzag flashes are not really zigzag at all; the flashes curve and wind, more like a river between its banks. “Sheet” or summer lightning is chiefly the effect of reflection against the clouds, so far away that we hear no thunder. The globular (Continued on page 160)

| type is more

MONEY MAKING OPPORTUNITIES SECTION 159 A FRANTIC CALL FOR MEN WHO CAN READ BLUE PRINTS OF BUILDINGS LEADS QUICKLY TO JOBS PAYING $4,000 to $12,000 A YEAR See how easy it is to get in the building game. Nowhere else does such simple training count for so much. Nowhere else can a man make $4,000 to $12,000 a year so quickly and so easily. Nowhere else are there so many countless thousands of openings as there are with contractors, builders, and real estate firms, who are constantly calling for men who can read blue prints. Six billion dollars a year is spent for building. Trained men are at a premium in this gigantic industry. Un- told thousands are needed at steady salaries far above the scale wage. DAYS EASY TRAINING \ PUTS YOU IN THE or 6 - BILLION - DOLLAR Oe SS BUILDING FIELD =e N O longer is it necessary to start at the bottom of the building trades and spend years to work up. Now you can get three years’ training in three months. There are no barriers to your success in the great outdoor building field. You do not need more than a common school educa- tion. We train you at home, in spare time, by the fascinating blue-print method with lessons that are as easy to read as your newspaper. These tested plans come to you from the oldest and largest school of building construction in the coun- try. This course is endorsed by leading contractors. These practical plans and lessons are the kind of training that puts men ia $5,000 to $15,000 jobs and in contracting businesses of their own. You learn from actual blue print plans—from practical building experts—you learn how to read all the plans, estimate the

IF YOU LIVE — and supervise e entire construction IN OR NEAR rd a gree I ag a ing a contractor has CHICAGO to chew when he un- dertakes the construc- tion of a building. Amazing opportunities are open to you when you know blue prints, plans, estimating and construction. There is Visit our School for Builders, open day or evening. housand men attend each year. Enter any time. You can get the sametrain- ing at home, by mail. Same plans; same les-

sons; same instruc- | building superintending tors. he Coupon | —the best outdoor brings all facts Free. profession on earth— that pays handsome

salaries and often a bonus. Clifford Scholl went from clerk to Ass’t. Superintendent at 49% increase in salary in 8 months. Thousands of contractors need men like Clifford Scholl. CHICAGO TECHNICAL SCHOOL FOR BUILDERS Dept. W-20, Chicago Tech Bldg. 118 E. 26th Street CHICAGO

tec Bane

Every Job Must Have a Contractor The building field is wide open for men who want to go into business for themselves. Henry Mehl, Pa., a een, now owns his own contracting business. urgert, Ill., stepped into a foremanship at 200% increase in salary. Busch, Kan., writes: “I have been offered $300 a month several times.” Boyes, Can., writes, “Your school has increased my wages 40% already.”” Patrick, Mich., says: ‘‘My salary has been increased 92%.” Marchand, La., writes: ‘‘My salary is now increased 196%.” If you really want more money—if you hope to own a business of your own—get into the building business i . ho matter what your job is now. No over- crowding in this tremendous field—room for thousands every day. Clerk or carpenter — office man or bricklayer— salesman or superintendent—it makes no difference. You can get into the building business quickly, easily. Or if you are in at present get this training now that you must have for success. FREE Trial Lesson Simply mailthe couponbe- /; low for an intensely inter J: esting free book “‘Howto f% Read Blue Prints,’’ and 3

full information. what fascinating fun £ this first trial lessonis. 3 See what amazing op- £— portunities openupfor you in the Six Billion Dollar Building Field. Don’t delay. Act £; now. Simply mail Fi=-:}: thecoupon below. a

Chicago Technical School for Builders, Dept. W-20, 118 E. 26th Street, Chicago, Il. Send me, without obligation, your free book, ‘‘How to Read Blue Prints”’ and full details of the course and the opportunities in the Building Field. It is understood that no salesman will call on me. Q oe < mn = 2 = o s SPCR CSESERESRETE SEAT EE EEE oe Z & 3 @

BE A PLUMBER and HEATING EXPERT Here's the opportunity of a lifetime for men who want to learn a real trade. Thousands of trained plumbers — from $75 to $150 a week. A few short weeks in our shops will fit you for any branch in the plumbing field Here you learn lead wiping, building and construction work, jobbing, estimating, blue prints and specifica- tions. No books, all actual, practical work under the supervision of master plumbers. Plumbers’ opportunities are everywhere, in the cities, small towns and the country. Send for our FREE booklet on how you can earn your expenses while learning in the world’s largest plumbing school. ILLINOIS PLUMBING WORKS SCHOOL 512-514 N. LA SALLE ST. DEPT. 412 CHICAGO, ILLINOIS

Furs Like New. Learn Fur Re- pairing and Cleaning. our secret processes. Learn glaz- ing, ironing and es Big demand, big need in every —_ srhood. A won- derful uncrowded f . Many earn $3 an Hour or a real busi: , far shop. Next month earnings start if you learn now. mow in your neighbo 4 at once for Free Book and get iY Nebrs 1 ON cee LAG @, Free Book freatest of Spare Time Money Makers. Big cpnertanity 3 Y hood. first =3 BS fall details of tats iw fall NORTHWESTERN EUR 1789 Sunderland Bidg.,

arene

Page 158

same blade. for American shavers everywhere rejuvenator. Makes hundreds blossom where only one grew before diagonal just like a master barber. Pressure decreases Your Last Chance To Get My Bond That HINK of it! 365 keen, cool shaves a year from the That's what a is doing This amazing invention marks such a radical advance in shaving comfort and economy that it deserves to be called much more than a stropper. Rather it is a blade of keen, quick shaves KRISS-KRCSS strops your blade (any make) on the energie Nickel jig to notify you when yo ur D ie is ready, with the eenest cutting edge that steel can take. And now for my smashing offer. To introduce KRISS- KROSS stropper, I will give you an amazing new kind of razor free. Really three razors in one. Can be made straight or T-shape in a jity. Comes with 5 special es. Use these blades and keep renewing them with KRISS- KROSS super-stropper. If any one goes back on you I'll recondition or replace them free! This sweeping written guarantee solves your blade problem for all AGENTS ! Make big money as a KRISS-KROSS ep- resentative. Many Earn $200 a week. J.C. Kellogg made $200 in 7 days. H. King earned $66 in one day. We show you how. Spare time workers, office and factory men —_ up to $10 extra day just showing KRISS - KROSS to friends. Check bottom of coupon and mail at once! time. I mean every word when I say drawn Dec. 3 Send for information on amazing tion today. * Rhodes Mfg. Dept. W-24i, Stis Pendleton Ave., St. Louis, Missouri. KROSS stropper guarantee and F piqntancceesesesocososscnsscoos® Please send me without obligation, “I'll keep you in Razor Blades for Life.” Get Details of Free Offer This astonishing offer is limited. Guarantee will be with- st and never offered again. So act quickly! -KROSS inven- They are never sold in stores—and are even more remarkable than I can tell you in this short space. Clip the coupon today. No obligation. RHODES MFG. CO. Dept. W-241, 1418 Pendleton Ave., St. Louis, Mo. KRISS. REE razor offer. IED iigs « pesacecsesines ( ) Check here if interested in becoming representative TTI) details of KRISS- MONEY MAKING OPPORTUNITIES SECTION Benjamin Franklin, Experimenter (Continued from page 159) rare, but the writer once watched such a ball roll down through a pine tree, fifty feet away, splitting it from top to bottom almost as neatly as a golden circular saw, about the size of the sun as it ordinarily appears to us, might have done it. And there is the recorded case of such a ball tumbling into a room, rolling across the floor and out through a crack in the wall without injuring any of the occupants. “Ribbon” or multiple lightning, still more rare, is due to a number of parallel flashes, so close that they seem to make one long ribbon. OCTOR STUBER, a contemporary of. Franklin’s, is said to have known him well and to have got from him the story of the historic afternoon. “His kite,”’ says Stuber, “was raised— a thundercloud passed over it—no sign of electricity appeared. He almost de- spaired of success, when suddenly he observed the loose fibers of his string to move toward an erect position. He now presented his knuckle to the key, and received a strong spark. How exquisite must his sensations have been at this moment! On this experiment depended the fate of his theory. If he succeeded, his name would rank high among those who had improved science; if he failed, he must inevitably be subjected to the derision of mankind, or, what was worse, their pity. Doubts and despair had be- gun to prevail, when the fact was ascer- tained in so clear a manner that even the most incredulous could no longer with- hold their assent.” AS Doctor Stuber accurate in his account? It is too late, now, to find that out. But nobody can deny that it is a fascinating picture of Franklin that he gives us. What other moment of his life could compare with that one? To stand up to a withering fire of questions by an English Parliament was one great hour. To stand up in the American Constitutional Con- vention and suggest equal state votes on matters of sovereignty—in other words, to save the Constitution by sowing the seed of today’s Senate as a means of securing really equal representation—was another great hour. But to be left standing out of doors facing single handed the greatest force in nature and sharply outlined against the blazing, crashing heavens? Printer, politician, inventor; author, diplomat, and pioneer American scientist: could Franklin himself have demanded more of fame than that? LENGTHENING the life of sponges by passing them through machines with spiked rollers so as to increase the honey- comb, is the idea of a Turkish inventor. After the sponges are brought up by the divers and cleansed of “milk,” they are washed, partially dried, and then perfo- rated wherever cavities are necessary for effectually cleansing them after everyday use. 5 Tube Console Tuned Radio Fre- circuit li- -S.N 'wo-tone wainut finish cabinet} built- Lo or ney is. Agents wanted in @every locality to take orders for fa- eros Premier radios. Made COM- PLETE in our factory, from Premier @parts exclusively, priced at one small eproft direct from ‘factory to user. But ic Commmuectons for you. Wri ite im: ms ew p! —y an soe he of dollars quick this a BIG DISCOUNT TO AGENTS! Get into the Radio business with our enor- 8 mous stock, and big factory back of you. p Write today for big discount on Demon- , strators to Premier ts! PREMIER ELECTRI CO., Dept. 103 Grace St. at'‘Ravenswood, Chicago DRAW CARTONS Turn Your Talent Into Money Cartoonists earn from $50 to $300 week—some even more. Remarkable new Circle System of Drawing teaches you in half the usual time. Send for booklet and sample re —_ ex- Piatning full details of the C NATIONAL SCHOOL OF CARTOONING 615 Penton Building Cleveland, Ohio. or experience required. We pa: cash commissions daily and big Dey 3a ger WRITE FOR FREE SAMPLES CARLTON MILLS, INC., Shirt Mfrs! 114 Fifth Ave., Dept. 86-K, New York AGENTS 500% PROFIT GENUINE GOLD LEAF LETTERS, Guaranteed to never tarnish. Anyone can put them on stores and office windows Enormous demand, large profits, Paul Clark says: smallest day $28. 70. R.L. Reel made $920 in two months. Write today for free sample and liberal offer to general agents, METALLIC LETTER CO., 433A N. Clark Street, Chicas, “STAMMERING| Ifs Guse and Gire * You can be quickly cured if you stammer. Send10 cents, coin or stamps, for 288 page cloth bound book on Stammering and Stuttering. It tells how I cured myself after Siammering and Stuttering for 20 years, ENJ ° wi 7536 Bogue Bidg.. 1147 N.U.St. Indianapolis Forest Rangers Men wanting Forest Ranger, Railway Mail Clerk, Special Agent, and other gov- ernment positions, $1500 to $4500 a year. Write for free particulars and list of positions. MOKANE, Dept. 218, Denver, Colo. BE A DETECTIVE Make Secret Investigations Earn Big Money. Work home or travel. ing work. Excellent opportunity. necessary. Particulars free. Write: GEORGE D. WAGNER Former Government Detective Fascinat- Experience un- 1968-P Broadway, New York See New Financial Department on Page 4—front section. aw — t- oe a oh ee. ae

Page 159

cinate e un- w York ent | foot off the accelerator, or maybe even Our Haphazard Signs (Continued from page 39) . step on the brake, and drop to fifteen or twenty miles before you pick out the other words. Then, if you're in a hurry, you open up again, with language rising involuntarily within you. And a little Jater on, when you see another big STOP you slide along at thirty-five, until sud- denly you notice that it reads— STOP! Dangerous Intersection Well, maybe that time it doesn’t make any difference. And then again, maybe it does. Every state in the Union ought to legislate misleading and dangerous adver- tising signs out of existence. GAIN, in the‘ease of route signs and directions, there’s an astonishing dis- crepancy between the best signs and the worst. More and more, now, the states are taking up the practice that started in Wisconsin, of marking route signs by number. We followed them quite easily through half the country—“ Number 22,” say, through Illinois, or “Number 14” through Missouri. On some of the main trails, such as the National Old Trails coast to coast highway, we found fairly clear markings a good part of the way, in red, white, and blue bands around the telegraph poles. But if you want a real grade-A puzzle, try to find the National Old Trails high- way, or any other, from Philadelphia to New York. Any stranger who can turn that trick without stopping about seven- ty-one times to ask directions is entitled to be best man at a wedding, or anywhere else. Try it in New Jersey around New- MONEY MAKING OPPORTUNITIES SECTION 161 Like a Pleasure = Trip—yet worth PC countless dollars to you 12 nage weeks in Chicago—then Big pay for life. ead how the Greer Shop plan starts you into wonderful future in either Electrical or Auto Engineering—by actual experience. Send coupon below now for Big Free Electrical or Auto Book ark, or Elizabeth, and into Jersey City. Cities and detours are the two things that make tourist routes particularly hard to follow. For a city solution, we can turn to Maryland again. There, at the city outskirts on most of the main route highways, we found big signboard maps with the through route clearly marked. ETOURS are, to be sure, always an abomination. When we went through Ohio and Michigan we found the trouble reduced to a minimum by splendid mark- ings for every corner. Even though the detours were sometimes bumpy, they could at least be followed easily. But many states are not so careful. In the first place, there’s a world of difference in the ways road commissioners steer you into detours. In some states an effort is made, whenever possible, to do half a road at a time, and allow travel to continue, with as little difficulty as possible, down the other half of the road, by providing places where two cars could pass, or widening the wing enough to make two lines of traffic possible, a lot of time and trouble is saved motorists. In other places the road commissioners block off highways for miles, causing need- less delay and expense for the very public they are supposedly trying to benefit. Again we found (Continued on page 162) and offer. Here you can fit Scene i department. y yourself for commercial operator's license if you wish. teach code as well as theory. Thoroughly practical from start to finish--as is the entire Greer training. View of part of the interior of the bungalow for practicing house wiring--right in the Greer Shops. You learn here r expe- rience--with an expert always at hand to show you how, One of the first lessons in the Automotive shops 18 on this ‘‘split chassis.’’ Every work- ing part shows. ust an example of the equipment that makes Greer training 80 sim- ple, easy and practical. Employment Our employment department is ready to help you—while in training and for life. Day and eve- ning classes. Low cost. Eas: Using the ** Weaver Crane”® in the Automo+ bile repair department. Here you learn about all up-to-date auto equipment--by ac- tually using it. Real experience on all makes of cars, under supervision of an expert. Service terms. Yes, Shorty, I had a wonderfut time in Chicago, and I’mali signed up for a real man’s" size job at man’s size pay. Don't you wish you had gone, too? ELECTRICAL ENGINEERING Lea.n how to earn $65 to $200 per week. Now is the best time you will ever have to get into this fas- cinating field. Inside work through the worst weeks of winter—in the bigcheeryGreerShops. Andatthe end of 12 weeks you'll certainly have thelaugh on the fellows who couldn’t decide—who act as if they're afraid to leave home. Practical Men Needed The demand for electrical men is growing faster and faster. More and more railroads are being electrified. Everywhere power companies are reaching out farther. hey have now actually started the tremen- dous task of electrifying the farms. Think what these developments mean to you! With this Greer training you will be a valuable man. You will get bigger pay than you probably .ever dreamed—and for work that you'll thoroughly enjoy. Don’t wait. Get full information quickly. Send coupon below. Actual Experience Here You learn in the big Greer Shops by really using the sort of equipment that you'll find out on the job. Individual instruction by experts. On our floors are over 200 motors, of various makes and sizes. Com- plete armature and stator depart- ment. Rotary converters, alternat- ing current generator, high tension line, automatic telephone panel— all here in our shops for your use. Course in practical radio fits you for commercial operator's license. You will enjoy our big illustrated electrical book. Send the coupon today—now. AUTOMOTIVE ENGINEERING If interested in autos, trucks or tractors, by all means get our big, free, auto book at once. The coupon below will bring it by return mail. You will find it full of valuable information about making your start in the auto business. Read letters—in this book—from some of the 50,000 men who are now suc- cessful and happy—thanks to Greer training. Real Auto Experience You learn in the Greer Shops by actual doing—first on the marvelous shop equipment, and later on customers’ cars, left for overhauling and repairing. Always under supervision of an effi- cient, friendly instructor. Every step is made simple and easy. Individual instruction. You go ahead as fast as you are able. No one is held back by some one else being slow. Learn Any Branch After you have the general training needed, you may specialize in any branch you wish, such as vulcanizing, trouble shooting, starting and lighting storage batteries or general repairing. There is great demand for men who really know. Hundreds of Greer trained men now own their own shops. You can do the same if you wish—starting on @ small scale, as soon as you finish this training. Don’t miss this chance by waiting. Send the coupon now while you have it before you. Greer College of Automotive & Electrical Trades CHICAGO, ILL. 1202, 2024 $. Wibash ERWIN GREER. President, Grogs Galiste= Please send me your FI 1 It is understood I am nto gated Go. 1 er for Electrical C) way. Automotive (-) urse i > eee coeceeseseses a eS ee ee ee ee ee ee ee ee eee ee eee and Free Railroad Fare to Chicago When You Enroll PATENTS ALL BUSINESS GIVEN PROMP Listed Patent Lawyer in the latest editions of the Rand-McNally Directory of Bank- ers and Attorneys, of Chicago, Ill.; The Baggott & Ryall Directory of Attor- neys, New York City; The Lawyers Guaranteed Directory, Detroit, Michigan; The Lawyers and Bankers Quarterly, published by the legal Directory Publish- ing Company of St. Louis Mo.; the American Lawyers Annual, Cleveland, Ohio WATSON E. COLEMA REGISTERED PATENT LAWYER Booklet Free Promptness Assured Send drawing or model for examination of Patent T AND PROPER ATTENTION 724-9th Street, N. W., Opp. U.S. Pat. Office ’ WASHINGTON, D.C. Highest References Best Results reliminary ce records

Page 160

162 Wuat I THINK OF PELMANISM By H. R. H. Prince Charlies of Sweden “Everyone should know his weak as well as his strong side, PELMANISM shows us the way to the improvement of character and an active life. I hope that PELMANISM will gain adher- ents in increasing numbers and show many an uncertain and hesitating wanderer the way to a happy life.” By T. P. O’Connor “Of two young men in business, one takes the PELMAN Course and the other does not. Other things being equal, the young man who takes the PELMAN Course will quickly pass the one who has not availed himself of the advan- tage in the race of life.” By Jerome K. Jerome “Every youngster comes into the world provided with a fine box 0: tools necessary for his life’s work. It con- tains Concentration, Observation, Imagination, Organization, and, above all, Memory. But nobody shows him how to use them. He finds out, with luck, towards the end of middle life, after years of bungling and despair, by the help of PELMANISM. am more than willing to help in making PELMANISM known to him. ought to have been taught it when he Was young. The sooner he takes it up, the better for him and for the country.” By Judge Ben B. Lindsey “The ‘twelve little gray books’ area remarkable achievement. Not only do they contain the discoveries of modern science as to the mind and its work- ings, but the treatment is so simple that tae truths may be graspeu by anyone of average education. “As a matter of fact, PELMAN- ISM ought to be the beginning of education instead of a remedy for its faults. First of all, it teaches the science of self-realization; it makes the student discover himself; it acquaints him with his. sleeping powers and shows him how to develop them. The method is exercise, not of the haphazard sort, but a steady increasing kind that brings each hidden power to full strength without strain or break.” By Hon. George Lunn “The man who knows his own capabilities and his own aims, at- tempts the things he knows he can do—and always succeeds. MANISM makes you know your- self. It makes you take stock. If pursued in honesty and industry, the course cannot fail to be 0! tremendous value to any man or SCIENTIFIC FREE MIND ~TRAINING It is impossible, in this space, to convey a true picture of what Pelmanism is, what it has done and what it can do for you. If you are dissatisfied, by means send for a copy of “Scientific Mind Training,” bese describes request. rrives for yourself whether or not you need the help ism. Do not say ““What’s the use” or “It’s all tommy- rot.”” When 550,000 others say Pelmanism helped them— when men of the highest standing recommend it in words of unstinted praise, surely you cannot justify yourself if you do not at least investigate by reading ‘Scientific Training.” If this book were to cost $10 it would be money well spent to purchase it. But the cost is nothing. Sending for it is an act that may mark the ning of a newer, healthier, happier life for you Isn't it worth the effort to mail the coupon? Do it nbw, for Frocrastination is a sign of weakness. THE PELMAN INSTITUTE OF AMERICA Approved as a Correspondence School under the laws of the State of New York 19 West 44th Street Dept. 8712 New York City The Peiman Institute of America, 19 West 44th Street, Dept. 8712 New York City I want you to show me what Pelmanism has actually done for over 550,000 people. Without obligating me, please send me your free book, “Scientific Mind Training.’ MONEY MAKING OPPORTUNITIES SECTION Our Haphazard Signs (Continued from page 161) the East behind the West in this respect. Hardly a highway in the country, for in- stance, carries more traffic than the Boston Post Road. Yet the history of that thor- oughfare, for the last ten years, is almost unbelievable. If I could have a dollar for every bump on the head I’ve had from hitting the top of the car on a detour from the Boston Post Road, I'd give the road commissioners a dinner. N KANSAS, Oklahoma and adjacent regions, to add to the gaiety of motor- ists, we found that a neighborhood rivalry had developed over routes. We would be traveling, let’s say, on the Southwest Trail. Conflicting signs set up by rival counties or communities that also wanted our trade, would have steered us off to the Coast to Coast Highway or some other trail. Then, there’s the confusing trick of insisting that you see the center of every town you pass through. Even though the main route goes, or should go, clear at the edge of the town, we would be shunted by the signs over to the main street, through the thickest traffic, and then back again. Varying state laws concerning speed and city regulations for traffic, we found, are still another source of trouble and danger. But this particular source of irritation has already been discussed in a recent issue of PopuLtar ScIENCE Monrtnaty. I would add only this: Maryland and a few other states have set up, where the main highways cross the state line, big signboards with the principal state road regulations and speed laws clearly outlined on them for visiting motorists. That’s a step worth copying. Finally, there’s the question of hand signals. Motordom’s millennium will have arrived when, and not before, the prescribed warnings from one motorist to another are as uniform as we'd like to have the traffic regulations. N THE Pacific coast, the generally ac- cepted signals are: Hand up for a right turn, straight out for a left turn, and down for a stop. But we found that a good proportion of the Middle West waves its arm in a circle for a right turn, holds it straight out or waves it in the opposite direction for a left turn, and holds it up for a stop. In the East one set of signals prescribes that you point straight out with your finger if you’re going to make a left turn; point at your own head as if you wanted to shoot your- self for a right turn; and hold your hand straight out with the palm turned back if you’re going to stop. But the most widely accepted rule in the East—at least around the larger cities—is just to dangle your hand over the left side of the car as a warning that you're going to do something. The fellow behind you has no idea what it may be; possibly you don’t know yourself. But at least—unless you’re merely knocking the ashes off a cigarette— he’s had a fair warning that you’re going to do some- thing; and from then on he travels at his own risk, as well as yours. Can You Fix it? Repair any auto fault, learn how NOW. You can do it easily in this new simple way. These FIVE Big Books are up to the minute on auto mobile engineering subjects; chock full of little known facts about construction, operation and repairs. Eleo tric wiring treated in complete detail—illustrations ang diagrams make everything clear and easily understood anybody. The most interesting and most practical set of books ever written on modern automobile engineering. Whether you want to fit yourself for garage owner, repair expert or merely wish to know more about your car, you will realize the values of these splendidly bound volumes, This is the new 1926 Edition with 70 new and up-to-date wiring diagrams. ‘‘NO MONEY” OFFER An amazing new plan of distribution brings these books to you for examination without one cent of payment tous, We don’t ask a penny of you, but ship the books to you FREE. Look them over—read them as much as you want to; note the splendid photographs and drawings and then if you decide you want them, send us $2.00, and then only $3.00 a month until only $24.80is paid. That is all; noth- ing more to pay us. If you send NOW we will include Consulting Membership—F REE Yes, we actually give you a certificate of membership in the AMERICAN TECHNICAL SOCIETY whichentitles you to free consultation on any subject related to Aute- mobile Engineering. Eighteen specialized experts are at your disposal—ready at any time to help you. With this ibrary and this membership you ought to be able scon te know all there is to be known about autos. Note:—In addition to all this, those who send now will be entitled to the services of our EMPLOYMENT DEPARTMENT without charge. We are in daily contact with firms all over the country who need good men and are willing to pay big. This service costs you nothing. Don’t miss this special offer. Send now. SSSSSRASKRHREHRPRESERREEERSRRSRESESERERESERESeeeeeeee American Technical Society, Automobile Division A-920, Chicago, Illinois You may send me your new complete Automobile Engi- neering library (1926 edition) 5 big volumes bound in flexo covers for ten days’ Free Examination. If satisfied, I will send you $2.00 then and $3.00 per month until the special low price of only $24.80 is paid, otherwise I will return them and owe you nothing. Include membership certifi- cate and employment offer. DMMB seh eden co ue cae kbabiswaiieee sae voakwiicws oie oie.ccelaae Address. ....... Seige eioinie se gece vse enie Snseeseeccesnae SUD cocwnanceesecceeiniens pases icicee ee ‘ SEMIBNORD | oo asrikicnus to cssaaa wens eukeaeesaesennea nee Ship Model Making How to Make Worth While Models of Decorative Ships By Captain E. Armitage McCann A practical book which tells how any handy erson can make models of a Picturesque arbary Pirate Felucca and a Beautiful Spanish Treasure Galleon. Ship Model Making gives full-sized draw- ings of every part required. This book describes how to make the models, what materials to use, how to fasten together and color them, how to make the spars and rig the ships. You do not need to know ships to make these models, the book describes everything in detail, but you may use your ingenuity and arlistic sense in decorating and can make them larger or smaller than the scale given. Profusely illustrated—Scale drawings Price, $2.50 POPULAR SCIENCE MONTHLY 250 Fourth Ave., New York City

Page 161

a, 1g — ue es ur ag in December, 1926 ‘Thrills of Modern Explorers (Continued from page 42) tide rises and falls, gates in the dams rmit maintenance of differences in water level during part of the tidal cycle. These differences produce the necessary heads of water for the produc- tion of power through turbines. They are trying it out now in England and France, says Mr. Marmer, to see how much “white coal” they can get from the ocean. On the Severn in England, with a twenty-foot tide range, and near Brest in France where it is over fifteen, experi- ments are being made. ‘Pegasus, or Problems of Transportation”’ By Col. J. F. C. Fuller. Published by E. P. Dutton & Co. “PDACIFIED tanks,” roadless vehicles with caterpillar treads, can be the means of opening to commerce the re- maining frontier countries of the world. War monsters that ten years ago first crunched their way over German trenches can now, in peaceful guise, overrun track- less countries and place at the world’s disposal their untouched riches, at the same time opening them to Europe’s sur- plus population. The remaining frontier countries of Africa, Asia, the British Dominions, South America, even our own Philippines or Alaska can thus be won far more rapidly than the “Iron Horse” won the American West. This is the belief of Colonel Fuller, former chief of staff of the British tank corps, and he bases it not only on experi- ments made in England, but on the recent exploit of Citroen caterpillar cars in cross- ing the Sahara. Tanks, he points out, need have no tracks laid for them, nor roads made; they need neither coal nor wood. This keeps the expense down; such vehicles, carrying a twenty-ton net load, can be run for slightly less than four cents a ton-mile, including overhead charges, depreciation, interest and all running charges. HE vistas this plan opens are limit- less and, as the tank expert points out, not so visionary. The latest British tanks make twenty miles an hour, and there are amphibious tanks that carry cannon across streams. A tank scaled the Palisades of the Hudson not long ago. What tanks can do, peaceful roadless vehicles can do, too. What other vehicle is there that can go safely about any- where except over a precipice? Not locomotives, trolleys, trucks or wagons. Yet most of the world is still roadless. So Colonel Fuller’s plan is to open with roadless vehicles, the “back country” that railroads do not reach. The wealth created will permit building new rail- roads later. He sees two types of pacified tanks. The smaller type with wheels in front and tracks in rear, would gather the produce from village, mine and farm and draw it to intermediate stations. Here it would be shifted to monster types, all tracked, plying between these stations and railroad termini. MONEY MAKING OPPORTUNITIES SECTION 163 They Laughed When I Sat Down At the Piano But When! Started to Play!~ “Can he really play?” I heard a girl whisper to Arthur, as I sat down at the piano. “Heavens, no,” Arthur exclaimed. @ note in all his life.’’ Then I gave them the surprise of their lives. I started to play. Instantly a tease silence fell on the guests. I played the first few bars of Beethoven’s immortal Moon- light Sonata. I heard gasps of amazement. My friends sat breathless—spellbound! I played on. A Complete Triumph! As the last notes of the Moonlight Sonata died away, the room resounded with a sudden roar of applause. Everybody was plying me with questions. ... “Jack. Why didn't you tell us you could play like that?” .. ‘“‘Wheredid you learn?” .. y was your teacher ?” Then I told them the whole story “It seems only a few months ago that I saw an ad of the U.S. School of Music mentioning a new method of learning to play which only cost a few cents a day! Without a teacher! And! no laborious scales or exercises. I sent for the Free Demonstration Les- son and was amazed to see how easy it was to play this new way. I sent for “He never played . ‘Who the course and found it Learn to Play | as essy as A.B.C.! Before I knew it I was playing By Note all the pieces I liked best. Mandolin Saxophone 4 coul 9 ra Mine or 3 classical numbers or jazz, Piano "Cello with equal ease! And I Organ Ukulele never did have any special Violin Cornet talent for music! Banjo Trombone Play Any Instrument or any other You, too, can now learn instrument music—right at home— in half the usual time. You can’t go wrong with this simple new method which has already shown almost half a million people how to play their favorite instruments. Just read the list of instruments in the panel, decide which one you want to play and the U. 8. School will do the rest. Free Demonstration Lesson Thousands of successful students never dreamed they possessed musical ability until it was revealed to them by a remarkable ‘‘Musical Ability Test’’ which we send entirely without cost with our inter- esting free booklet and Demonstration Lesson. Right now we sre making a Special offer for a limited number of new students. Mail coupon now. Instruments supplied when needed, cash or credit. U. S. School of Music, 812 Brunswick Bldg., N.Y.C. CRESS SSHSSSSRESSSTRSSSESEKESEESECEEREEEEEEAEEEEEEeeeeee U. S. School of Music, 812 Brunswick Bidg., New York City. Please send me your free book, ‘‘Music Lessons in Your Own Home,” with introduction by Dr. Frank Crane, Demonstration Lesson and particulars of your Special Offer. I am interested in the following course. Have You NMC Ol COGRNG ss 0666 dave ben viaewoed PRS be ® ING a os. 54:6 50.0 5 n1¢s 45st c.cslaeaee WM clslecme a aeaeneoae FT ST ET ET ET ee ee CUB ae ols Scucle sne teleat State..... Learn How toBXX JIMMY DeFOREST = BOXING COURSE DEVELOPS CHAMPIONS BY MAIL In 20 weeks, under the System of Jimmy DeForest, World's Greatest Trainer and Maker of Champions, you will master the priceless knowl- edge that made Jack Demp- sey his millions, and fortunes for a host of other Jimmy DeForest- trained ring stars. Every 6 months 30 are selected from all classes and recommended to leading pro- moters for boxing engagements. That’s how pupils are brought to the front at once. Boys who were once rank amateurs are today earning big money; weaklings have been made strong, courageous; men have learned the art of self-defense. Send today for the now fa- mous book, *‘ ‘olden Age of Boxing’’ greatest book of its kind ever written; full of valuable information, photos of great fizhters and pupils who became successes over night. Enclose 10c to cover cost of mail- ing, etc. Write now. JIMMY DeFOREST BOXING COURSE 347 Madison Ave., Box 2212, New York City High School Course in 2 Years This simplified, complete High School jurse—specially prepared for home study by leading professors—meets all require- Over 200 noted En x iness Men, and Peewee A ave your inclinations may be, you can’t hope te succeed without specialized training. Let Drexel Ave. & S8th Street Dept. H- 975 Chicago ments for entrance tocollege, business, and 20 Oth er leading professions. C pare the special instruction for success. No matter what us give you the practical training you need- American School American School, Dept Ave. and 58th St., Chicago Send me full information on the subject and how you will help me win success in that line. ees Architect ...... Electrical Engineer steel Building Contractor --. General Education Be Automobile Engineer soe Lawyer oscest Civil Engineer .. Mach. Shop Practice sieeth Structural Engineer «+++. MiechanicalEngineer casas Business Manager «-.. Steam Engineer we PA. &Auditor _...... Sanitary & Heating coonee r +. Surveyor & Mapping asses Draftsman & Designer woe igh Scheel Graduate II ececscscctescinecoccscieceteseinescsdeneennsnosastsseotenseesaccsones sutesceiencelan . \ . .v 6c ric ty Know the facts in Electricity. They mean_more \ money and better position for you. Hawkins Guides | tell you all you need to know about Electricity. | Every important electrical s covered 80 you .can understand it. Easy to study and apply. A com plete, practical working course, in 10 volumes. | Books are pocket size; flexible covers. Order a set | to-day to lovk over. HAWKINS GUIDES oP i A VOLUME MONTH 3500 PAGES 4700 PICTURES LA 4 These books tell you all about — Magnetism — Induction — Experiments — Dynamos— Electric Machinery — Motors — tures — Armature Windings — Installing of Dynamos— Electrical Instru- ment Testing—Practical Man ent of Dynamos Motors--Distribution Systems- tans td oe —Sign Flashers—Storage Batteries—Principles of Alter- nating Currents and Alternators—Alternating Current Motors—Transformers—Converters— Rectifiers—Alter- nating Current Systems—Circuit Breakers—M ing Instruments—Switch Boards—Wiring—Power Stations —Installing —Telephone—Telegraph —Wireless—Bells— Lighting—Railways. Also many Modern Practical Appli- cations of Electricity and y Reference Index. SHIPPED TO YOU FREE Notacent to pay until you see the books. Noobligation tobuy unless you aresatisfied. Send Coupon now— —and get this great helplibrary and see if it is not wort $100 to you—pay $1.00 a month forten monthsor return it. THEO. AUDEL & CO. 65 W. 23rd St., N.Y. Please submit for examination Hawkins Electrical Guides (Price $1 each). Ship at once, prepaid, the 10 numbers. [f satisfactory I will agree to send you $1 within seven days and to further mail you $1 each month until paid. COPRIIOE do e vies ciisccdesciecinenes INO sia dase sx cadinnchaweehenenuree 12T34

Page 162

The only man who could talk to the Superintendent “Soon after I began studying,” a student wrote to us the other day, “we had a change.in management at our plant. I cer- tainly was glad then that I had decided to study in my spare time. For, thanks to my I. C. S. course, I was the only man in the organization who could talk to the Superin- tendent in his own language. As a result, I was promoted over men who had been here from ten to twenty years. My salary has been increased 90 per cent in the last ten months.” pe a true story of what just one I. C. S. stu- dent has done. There are thousands of others. Every mail brings letters from men and women tell- ing of promotions and increases in salary due directly to spare-time study. One hour a day, spent with the I. C. S. in the quiet of your own home, will prepare you for success in the work you like best. Yes, it will! Put it up to us to prove it. Mail this Coupon To-dey | ~ INTERNATIONAL ae ay te SCHOOLS Scranton, Penna. Oldest and ho Bh ssosieanbene schools in the world Without cost, please tell me how I can qualify for the position or in the subject before which I have marked an X: BUSINESS TRAINING COURSES |Business Management Salesmanship Industrial Management Advertising Personnel Organization etter Letters Traffic >) eae Show Card Lettering Business Stenography and Typing Banking ani | Banking Law Business English Accountancy (including . P.A.)LICivil Service Nicholson Cost Accounting Railway Mail Clerk Common School Subjects Private Secretary High School Subjects Spanish O French Tilustrating TECHNICAL AND INDUSTRIAL COURSES ring Archi A Arenitects” Blueprints Mechanical Engineer C)Contractor and Builder echanical Draftsman Architectural Draftsman ae Shop Practice Concrete Builder Bookkeeping

00000 Structural Engineer Chemistry () Pharmacy Automobile Work H agricalt Engines Railroad Positions Gas Engine Operating Civil Engineer Surveying and Mapping Metallurgy 0 Mining Agriculture and Poultry Steam Engineering [J Radio Mathematics OS BR SO A a Ae 2 SE ee eee Street PIE bitin <tbcvovbessenccccsoonscsonsstoceeess socbevssebsensnetbvensevesoosesecsocce acetal eit hdasesccnnecnpeg=- NOD ~cninpennversesogur senpespeedhoeesooe II ais ssc urpsientepiincunbneabersesentvarspeestestiivosshuoosssareessnseegec+e If you reside in Canad, send this coupon to the Interna- tional Correspondence &shoole Canadian Limited, Montreal

at HOME Teachers, authors, students and all who wish a broader outlook may start any day courses in Psychology, Art,Government, Economics, History, Literature, Edu- cation, Religion, Foreign Languages, Sci- ences and other subjects. These courses yield credit toward a Bachelor degree. The Aniversity of Chicago 135 Ellis Hall Chicago, Illinois

MONEY MAKING OPPORTUNITIES SECTION

Complete List of Winners in July Picture Contest FIRST PRIZE—$500 Harold Stewart, San Diego, Calif. SECOND PRIZE—$100 C. R. Helper, Sturgis, Mich. THIRD PRIZE—$50 Egbert C. Everest, Plattsburgh, N. Y. TEN $10 PRIZES Carol Young Alwin, Minneapolis, Minn. Clement Birch, Joliet, Ill. Louis C. Flocken, Wilbraham, Mass. Marguerite Goepel, Orlando, Fla. Matt J. Hefti, LaCrosse, Wis. Mrs. John Kruger, Toledo, Ohio E. A. Oliver, Los Angeles, Calif. Alfred T. Renfro, Bellevue, Wash. Harry R. Samuelson, Washington, D. C. Ruth Laura Winders, Columbus, Ohio FIFTY $5 PRIZES F. C. Arnold, Rolling Bay, Wash.; Charles Blessing, Montrose, Colo.; Arthur Brown, Danvers, Mass.; John DeQ. Briggs, St. Paul, Minn.; Ernest Baird, Venice, III.; Mrs. J. Norman Ball, Philadelphia, Pa.; Olive Boyd, Los Angeles, Calif.; Isabel Car- lock, Knoxville, Tenn.; C. E. Cortright, Spokane, Wash.;-John R. Chapman, Cam- pello, Mass.; E. Clemons, Los Angeles, Calif.; C. W. Chance, Cleveland, Ohio; Ruth O. Dehn, Seattle, Wash.; Charles L. Doyle, Tucson, Ariz.; Alfons J. Finck, Salt Lake City, Utah; Wm. W. Fairbanks, Fort Bragg, Calif.; George H. Fader, White Plains, N. Y.; Olin Potter Geer, New York City; Henry S. Gagnon, Portland, Ore.; E M. Gorrell, Van Wert, O.; Burnace Hamm, Orlando, Fla.; Matthew H. Hopkins, Ha- bana, Cuba; S. R. Hannah, Sparks, Nev.; Harvey J. Holt, Santa Barbara, Calif.; G. R. Hatchett, Fairville, N. B., Canada; E. A. Johnson, Pueblo, Colo.; Mrs. G. A. Kelser, Fort Collins, Colo.; Bernice L. Lackey, Middletown, Ohio; Willie L. Ley- sath, Charleston, S. C.; E. G. Morse, Everett, Wash.; Harry W. McGue, Lorain, Ohio; Billy McQuilkin, Roanoke, Va.; George E. Mears, Albany, N. Y.; Gillian R. Monell, Denver, Colo.; E. J. Marston, Tepic, Mexico; John O’Neal, Yakima, Wash.; Vernon Poulsen, Ogden, Utah; J. W. Parker, Taneycomo, Mo.; Frank C. Rice, Newport, R. I.; Charles E. Richter, Oakland, Calif.; Mrs. Alfred R. Roades, St.. Louis, Mo.; Mr. and Mrs. Raymond Rosson, Jacksboro, Tenn.; Arthur Reall, Los Angeles, Calif.; Rose Hamilton Sim- mons, Boston, Mass.; E. J. Theopold, Leavenworth, Kan.; E. T. Wheeler, Nor- ristown, Pa.; Mrs. Frederick F. Webster, Cleveland, O.; Hazel A. Warner, Los An- geles, Calif.; E. E. Terry, San Diego, Calif.; Frank S. Snyder, Poughkeepsie, N. Y.

Sealing Wax Hardens Tools HARD and lasting edge is put on tools by the use of sealing wax, accord- ing toa report from Germany, where the method has been adopted by a cutlery maker. The tools are first heated to whiteness and then plunged repeatedly into the wax until they will no longer pierce the latter. In the process, it is said, the steel becomes almost as hard as a diamond, and when touched with a little oil or turpentine, is excellent for engraving or drilling, for watchmaker’s use, and also for cutting the hardest metals for the longest time without blunting.

CHRISTMAS SEALS and help us to keep you healthy hed MERRY CHRISTMAS

THE NATIONAL, STATE AND LOCAL TUBERCULOSIS ASSOCIATIONS OF THE UNITED STATES ~~ SLE __ Saal

The Electrician’s Wiring Manual By F. E. Sengstock, E. E. Contains all the information needed for the proper installa- tion of lighting and power sys- tems in housing and other buildings. It completely covers inside electrical wiring and construc- tion in accordance with the National Electric Code. Pocket size—flexible binding 448 pp. Price $2.50 POPULAR SCIENCE MONTHLY 250 Fourth Ave., New York City

COPY THIS SKETCH and let me see what you can do with it. Cartoonists trained by this school are earning from $50.00 to $200.00 or more r week. The Landon Picture Chart Method of teaching makes original drawing easy tolearnat home in sparetime. send sketch with 6c in stamps for full information and sample chart to test your ability. Please state age THE LANDON SCHOOL 1451 National Bldg. CLEVELAND, 0.

a a aah me

Page 163

— vo “How I Licked Wretched Old Age at 63” “I Quit Getting up Nights—Banished Foot and Leg Pains. . . Got Rid of Rheumatic Pains and Constipation . «- Improved Embarrassing Health Faults ... Found Renewed Vitality. “At 61, I thought I was through. I blamed old age, but it never occurred to me to actually fight back. I was only half-living, getting up nights . . . embarrassed in my own home. . . constipated , . . constantly tormented by aches and pains. At 62 my condition became almost intolerable. I had about given up hope when a doctor recommended your treatment. Then at 63, it seemed that I shook off 20 years almost overnight.” Forty—The Danger Age These are the facts, just as I learned them. In 65% of all men, the vital prostate gland slows up soon after 40. No pain is experienced, but as this distressing condi- tion continues, sciatica, backache, severe bladder weakness, constipation, etc., often develop. Prostate Trouble These are frequently the signs of prostate trouble. Now thousands suffer these handicaps needlessly! For a prominent American Scientist after seven years of research, discovered a new, safe way to stimulate the prostate gland to normal health and activity in many cases. This new hygiene is worthy to be called a notable achievement of the age. A National Institution for Men Past 40 Its success has been startling, its growth rapid. This new hy- giene is rapidly gaining in national prominence. The institution in Steubenville has now reached large proportions. Scores andeven hundreds of letters pour in every day, and in many cases reported results have been little short of amazing. In case after case, men have reported that they have felt ten years younger in six days. Now physicians in every part of the country are using andrecom- } mending this treatment. ‘ Quick as is the response to this new hygiene, it is actually a pleas- ant, natural relaxation, involving no drugs, medicine, or electric rays whatever. The scientist explains this discovery and tells why many men are old at forty in a coat taal now sent free, in 24-page, illustrated form. Send for it. Every man past forty should know the true meaning of those frank facts. No cost or obligation is incurred. But act at once before this free edition is exhausted. Simply fill in your name below, tear off and mail. The Electro Thermal Company 4064 Main Street Steubenville, Ohio THE ELECTRO THERMAL Co., 4064 Main Street, Steubenville, Ohio. Western address: Suite 40-G, 303 Van Nuys Bldg., Los Angeles, Calif. MONEY MAKING OPPORTUNITIES SECTION Here Are Correct Answers to Questions on Page 48 1. At the small town of Summerland, Calif., oil seepages were noticed at the seashore. Some of the wells drilled ac- tually are out under the ocean. The der- ricks and pipe lines are’ built on stilts several hundred feet off shore. 2. According to the census of 1920, the center of population was located in Owen County, Indiana, Fifty years ago it was near Cincinnati. It is slowly moving west, as the settlement of the Western states increases. 3. In the summer, northern Alaska has days twenty-four hours long. On the other hand, the winter season brings con- tinuous night. 4. In the bottom of the valley in | which lies the City of Mexico, there are still several small lakes. In one of these, Lake Xochimilco, natives have built gardens on masses of peat that float on the surface of the water. Here are raised most of the fresh vegetables that the City of Mexico consumes. 5. Off the coast of southern Florida the current of the Gulf Stream averages about two miles an hour. 6. South America. Vast areas in western and southern Brazil, in northern Bolivia and in the interior of Colombia and Venezuela have never been examined with completeness by civilized people. Even in Argentine there are areas which are imperfectly known. 7. This famous building is an ancient fortress, still standing on a slight hill within the city of London on the north bank of the Thames River. 8. All through the equatorial or mid- dle part of Africa the natives communi- cate from village to village in this way. The codes by which messages are sent are not well understood by the whites, but news is spread in this way with great rapidity. 9. Near the ancient city of Thebes in southern Egypt, not far from the modern town of Luxor, there still stand two large statues cut out of stone by the ancient Egyptians. It is said that the heat of the rising sun caused the stone of one of the statues to expand so that a sound was produced as though the statue spoke. 10. This is a custom in the southern part of India, where certain kinds of so- called “edible earth” are common ar- ticles of commerce. Balls of this earth may be purchased almost anywhere in the bazaars. The reason for this curious custom is obscure. The earth contains little nutriment, if any, although it is barely possible that some of its mineral constituents, for example, iron, may be slightly beneficial to the health. 11. This was one of the customs of the native kings who ruled the Hawaiian Islands before the conquest of these islands by the whites. These cloaks were made from the feathers of a small bird native to the islands. Many women worked for a lifetime collecting and piecing together enough of the feathers to make a cloak for the king. 12. The tallest known ferns exist in the Hawaiian Islands, where they grow to a height of thirty or forty feet. Astonish Your Friends — Gain that magnetic popularity that makes you the center of any crowd. Business and social success is assured the man who can perform mystifying tricks. You can earn big money either on the side or as a professional, as well as being the most popular per- son in your crowd. Why envy others’ skill? You can learn Magic yourself, quick and easy. Earn Up to $1000 a Month Even sleight-of-hand, generally su to re- quire long practice, 5 NOW ne. to learn. For Dr. Harlan Tarbell, one of the really Great Magicians, has finally opened up the secrets of his profession in a completely illustrated course offered at a merely nominal cost. Through the wonderful Tarbell System ‘ou will be able to mystify and entertain your iends with cmp tricks taught in your v first lesson. er that Dr. Harlan Tarbell takes you through the entire maze of sleight- of-hand, card tricks and elaborate stage diver- tisements. The apparently superhuman doings of the accomplished magician becomes as simple as ‘ABC when you just know how. Mail Coupen Special Offer ! There is a tremendous demand for magi entertainment. Clubs es, Charity and Social affairs—all will pay high fees to the man who knows Magic. . Harlan Tarbell really gets as high as $250 for a half hour’s work right now. portunity everywhere to make money aside from your regular occupa- tion. Salesmen find it a tremendous asset. Find out all about this unprecedented oppor- tunity to learn Magic. The coupon brings full details without any obligation. Mail it TODAY. Tarbell System, Inc. 1926 Sunnyside Ave.,Studio 13-69 Chicago oe OMA RERORT SHR HHSSSRSRRBAERBHES Tarbell System, Inc. 1926 Sunnyside Ave.,Studio 13-69 Chicago Tell me all about Dr. Tarbell’s new and simple system by, which I can learn the secrets of MAGIC. No obligation on my part.

Page 164

166 POPULAR SCIENCE MONTHLY RLIIZE REG.U.S.PAT.OFF. R eee A Name that Means 200 Years of Fine Musical Instrument Making. we Read the remarkable life-work of Hans Adam Wurlit- zer, master violin maker. In the Saxon town of _Schoneck he founded a wonderful reputation for true F- musical craftsmanship. For 200 years, down to the present day, seven generations of the Wurlitzer family, from father to son, have carried on his excellent creative work. To- day, you will find in every Wurlitzer instru- ment the same superb quality, the same high character, which two centuries ago made world-famous musicians travel from afar to Hans Adam Wurlitzer’s cottage. | BreeTrial your own home any \WuRLIIZER Instrument Try any Wurlitzer musical instrument in your own home. Examine it, play it, show it to your friends—make com- parisons. We now make this liberal offer because we want you to see the wonder- fully fine workmanship and hear the full, rich tone of genuine Wurlitzer instru- ments. No obligation—no expense, but Easy Payments will be arranged to suit your convenience should you desire to buy. Just send the Coupon today. Jena joy FREE BOOK The greatest and best illustrated musical catalog ever published. Over 3000 articles described— every known instrument and accessory—many of them shown in full colors. Gives lowest prices and details of Easy Payment pian. Sent Free. No obligation. Use the coupon. Learn to Play in your own home A. special scholarship in a nationally famous school of music is now furnished FREE with every Wurlitzer instrument. Special home study method quickly teaches you to play. Many graduates of this school are successful professional. musicians. The Rudolph Wurlitzer Co., Dept. 1789, 117 E. 4th St., Cincinnati 329S. Wabash Ave., Chicago 120 W. 42nd St., New York 250 Stockton St., San Francisco Send me your Free Book on musical instruments. Also your Free Trial, Easy Payment Plan and Special Free Scholarship Offer. No obligation. > Q i t s seecenccceccceueuesssencceucceccces, eee ie ae : sespesseeeopyright, 1656, The Rudolph Wurlitzer December, 19% CONTENTS| of This Issue Editorial—Calvin Coolidge, Handy rahe etitdinn «hee ecas eae a Ree By Edgar C. Wheeler “It’s Brains Against Brains— Fighting Gorillas!”............, By Frank Parker Stockbridge Strange New Crime Remedies By E. E. Free How a Hurricane Gathers Fury... What Science Knows About Your Feet and Your Shoes........... By John Amid A Camera Hunter Tells His Secrets They Can Fly with Their Eyes Shut! By H.C. North Harnessing Thirty Million a By Manus McFadden Folding Plane for Submarines. ... . By Edwin Ketchum The New Wonders of the Sea By Robert E. Martin Amazing Ways We Use Waste.... By Lee Carter Tunney Tells How He Won the he rae eA Se Gh kg ewe kan Sb By Ed Van Every How Many Words Do You Know? Is Your House Heated Properly?. . By John R. MeMahon You Can Do These Tricks........ By Kenneth B. Murray Benjamin Franklin, Experimenter . By Archibald Douglas Turnbull Eight New Tests—Try Them!. Our Haphazard Roadside Signs... . : By Myron M. Stearns Keeping Up with Scierce......... Thrills of Modern Explorers...... By Thomas M. Johnson July Picture Contest Winners. .... New Airplane Built Like a Gull... Latest Are Welding Feats Amaze TEI E TC CE PEE Ingenious “Gun” Splits Logs into IER Oe POPPE OEE Giant Camera Snaps a Whole City | eee: Automatic Die Caster for Small I ic asus caine + vary s Yardmaster Directs Switchman by The Uncommon Run of Things... . Famous Oarsman Invents New ae Piece of Cork Inflates Life Belt RI... oo eas seers New Glass Protects Movie Actors’ 0 a ee Spiral Garage May Solve Our Park- eS ere Inventors’ Ideas That Are Easing sn ic abc teehee Tuning Up Your B-Eliminator.... By Harrison Lewis If You Plan to Buy a Radio Set for SS A OY = PPO PTET By Alfred P. Lane Hints for Radio Beginners........ Radio in New Forms............. What’s Wrong with Spratt’s Car?. Seven Useful Ideas for Your Car. . Home Workshop..............- Better Shop Methods.......... And More Than Two Hundred Other Articles and Pictures 46 47 48 50 60 61 62 64 72 1S) This seal on a radio, tool, or oil burner enteetenin signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 165

Secember, 1926 POPULAR SCIENCE MONTHLY 1 The liquid gauge, ewhich measures to : the one-one-hundred- i thousandth of an inch. y 8 | 0 Q = OO | “The'tule of thumb’ 7 ZS OVETY. . . 8 . ING THUMBrules no more. The rule of thumb, with all its costly guesswork, has no place in Western Electric telephone making. : Here exact measuring standards are the rule, 2 : precise in many cases to the ten-thousandth part of an inch. And this habit of being exact controls ' every factory activity—in the systematic planning of the great task of telephone production, in manu- facturing to known standards of quality, in con- stantly improving methods of work—not in hap- ; hazard experiment but by scientific attack by a group of skilled industrial engineers. Looks like a bomb, but really a little At the same time, as makers of the nation’s “‘dark room’ which permits the in- ee : z spector to know exactly whether a tiny telephones, Western Electric is meeting its respon- seuitchbeard lamp auneeaada iene ) sibility by holding down the cost of telephone. apparatus to a figure well below the increased cost , of general commodities. ] esfern Electric j SINCE 1882 MANUFACTURERS. FOR THE: BELL .SY¥S8 734 © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 166

POPULAR SCIENCE MONTHLY (CALVIN COoOLIDGE. Handy Man weg AN EDITORIAL ALVIN COOLIDGE, President of the United ( States, was seated in an old-fashioned green wicker rocking chair. His felt hat was pushed comfortably back on his head. On the floor sat Bruce Barton, an old friend. They talked of this and that, as friends will. Plymouth, the little Vermont village, where Coolidges have lived for generations, was mentioned. And, according to Mr. Barton, who wrote of the chat for The Associated Press, the President said: ‘Plymouth gives me something I need in my work and cannot get anywhere else. If I find a strap broken, I like to get out the tools used by shoemakers, make a waxed end and repair it. I like to do a little blacksmithing around what is left of our old shop, try my hand again with the carpen- ter’s tools, go out and repair the fence where it is breaking down, and mend the latch on the kitchen door.”’ D for thought there. The head of the biggest business institution in the world, the United States Government, finds inspiration and solace in the little tasks you and I do about our homes. He is one of a constantly growing group of American leaders who know the value of a tool chest and a home workshop in giving the human mind the rest it needs. Calvin Coolidge, Handy Man! It is a title the President can wear with honor. Thousands of Americans, in every walk of life, wear it. Hun- dreds of them write to this magazine every week. My banker is building a radio set and my lawver is shingling his house. Look about your town. You can find doctors mending leaky wash boilers, min- isters making ship models and accountants build- ing bobsleds. And each of them is doing his daily task a little better because of the stimulation he gets from his hobby. pe President is right. Plymouth gives him ‘ J something he needs in his work. There is something about handicraft that brings a man closer to the kind of people who make up the back- bone of the nation. The thought of the President as a handy man allies him with you and meand that father who, just before Christmas, sneaked up to his home workshop in the attic, praying that his little daughter Mary wouldn’t discover him. ‘And why?”’ asked Gilbert P. Symons, the Cin- cinnati clergyman who told us about him. ** Doll’s house! Two stories with bathroom and cupola. Glazed windows. Green and white color varnish. Real shingles made from printed linoleum. A house that Mary won't forget if she lives to be ninety. A house that is holy because that father made it with his own hands. A man that is twice a father because he is a handy man!’ I can’t help but feel that perhaps Mr. Coolidge is a better President because he isa handy man.—S.N.B. December, 192 December, 1926, Vol. 109, No.6. Popular Science Monthly is published monthly at 250 Fourth Avenue, New York, N. Y., by the Popular Science Publishing Co., Inc. Entered as second-class matter Dec. 28, 1918, at the Post Office at New York under the act of March 3, 1879: additional entry as second-class matter at Chicago, Illinois. Entered as second-class matter at the Post Office Depart- ment, Canada. Printed in U.S. A. Copyright 1926, by the Popular Science Publishing Co., Inc. Single copy, 25 cents. Yearly subscription to United States, its possessions, and Canada, $2.50; foreign countries, $3. The contents of this magazine must not be reprinted without permission. In presenting in its editorial columns numerous stories of new se of applied science, Popular Science Monthly does not underwrite the business methods of the individuals or concerns producing them. The use of Popular Science Monthly articles for stock-selling schemes is never authorized. O. B. Capen, President and Treasurer; R. C. Wilson, Vice-President; A. L. Cole, Secretary.

Page 167

Dues “The new Balkite’ 4 POPULAR SCIENCE MONTHLY at $2759 and the Balkite Trickle Charger fun i The New Balkite Charger, MODEL J. Has two charging rates. A low trickle charge rate and a high rate for rapid charging and heavy duty use. Can thus be used either as a trickle or as a high rate charger and combines their advantages. Noiseless. Large water capacity. Visible electrolytelevel. Rates: with 6-volt battery, 2.5 and .5 amperes; with 4-volt battery, .8 and .2 amperes. Special modelfor25-40cycles. Price $19.50. West of Rockies $20. (In Canada $27.50.) Balkite Combination Whenconnectedtothe“A” battery this new Balkite Combination RadioPower Unit supplies automatic power to both “A” and “B” circuits. Controlled by the filament switchalready on your set. Entirely automatic in operation. Can be put eithernearthe set or in a remote location. Will serve any set now using either 4 or 6-volt “A” batteries and re- quiring not more than 30 milliamperes at 135 volts of “B” current—practically all sets of up to 8 tubes. Price $59.50 (In Canada $83.) AllBalkite Radio Power Units operate from 110-120 volts AC current with models for both 60 and 50 cycles. The new Balkite Charger is also made ina special model for 25-40 cycles. tis ish all radio |} power from the light socket ) The light socket is your most conven- ient source of radio power. Use it by adding the new Balkite “B” and the Balkite Trickle Charger to your radio set. Balkite“B”—the unique“B” power supply —eliminates “B” batteries en- tirely and supplies “B” current from the light socket. The new Balkite “B”-W at $27.50* serves any set of 5 tubes or less requiring 67 to 90 volts. Balkite “B”-X at $42* serves sets of up to 135 volts and 8 tubes. Balkite “B”-Y at $69* serves any standard set. TheBalkiteTrickleCharger at $10* light socket“A” power supply. With 4-volt batteries it can be used as an intermittent charger, or. as a trickle charger if a resistance is added. Both Balkite “B” and the Balkite Trickle Charger are noiseless in oper- ation. Both are permanent pieces of equipment, with nothing to renew or replace. Other than aslight consump- tion of household current, their first cost is the last. Both are built to con- form with standards set by the Underwriters’ Laboratories. Over 650,000 radio sets are already Balkite equipped. Make yoursalight is probably the most socket receiver too by popular of all charg- adding these Balkite ers. Over 200,000 The Balkite Units. Enjoy the were purchased dur- || ‘Radio Symphony Concerts |} pleasure of owninga ing one season and with WALTER DAMROSCH radioset alwaysready are now in service. and the New Y ork Symphony to operate at its best. Instead of operating These concerts will be broad- *Balkite Trickle intermittently at a a ee ak Charger $10.50 west high rate, it operates On intervening Saturdays Mr. of Rockies, In Can- continuouslyat alow Facet ies pe atl Ao 5 ada, Trickle Charger rate, thus automatic- Hasire Steediaed ¥en seeeee $15;"B”-W $39;“B”- ally keeping the bat- WEEI, WGR, WHI, WCAE, || %$59.50;“B”-Y $96. tery at full charge. In WSAI, WTAM, WWJ, WGN, Fansteel Products effect it converts your ee ee Co., Inc., North Chi- “A” battery into a cago, Illinois. FAN STEEL Bal kite - “Radio Power Units 5 r{S} This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 168

The purpose of this new Department is to help Readers of POPULAR SCIENCE MONTHLY save money and invest it safely and profitably POPULAR SCIENCE MONTHLY December, 19% How HERBERT CLARK Gained Financial I ndependence in 15 Years By WALLACE AMES, Financial Editor R. FOWLER had been Presi- dent of the First National Bank from its beginning and under his direction it had grown tobealarge institution. But the Bank’s expaision had not changed Mr. Fowler much. His desk was still out in front where he could meet cus- tomers. He always made it a point to keep in close personal touch with them. For over thirty years Mr. Fowl- er had watched the progress of the Bank’s depositors,—or at least the progress 33 some of them,—the ones who were getting ahead. He had lived a full business life close to the financial affairs of his fellow-townsmen. He knew a lot about the money problems of the average man. It was the last business day of the year. After banking hours Mr. Fowl- er and the Cashier were going over the Bank's statement together. On this particular occasion a whole pa- trade of the Bank’s depositors seemed to be passing before Mr. Fowler's mind and finally his conversation drifted into an unusually interesting channel. — **t\O YOU know, Fred,”” remarked Mr. Fowler, ‘I have come to the conclusion that it takes only about fifteen out of theseventy yearsofa man’s life tosettle his financial success. When- ever I look over the records of the men who carry their personal accounts here in the Bank I am impressed with the unusual importance of the com- paratively short stretch of fifteen years in the average man’s welfare. And often I wonder why more men, young men, middle-aged men, and even older men, do not figure out how much they can do in fifteen carefully planned years and how much easier and pleasanter everything would be for them as a result “To illustrate what I am driving at just take some of the men who have been calling on me today. Take the case of Herbert Clark who has just been made Vice-President of his com- pany. Herbert came to this town right from college and started to work for $18 a week. He is still under forty, yet he told me today that he was worth $53,000. He has $8,000 equity in his house, owns $20,000 stock in his company and $25,000 in good bonds. He has done all that in a little over fifteen years.” A New Service for Readers of POPULAR SCIENCE MONTHLY fips new Department is to help readers in the establishment of proper financial programs at the beginning of their business careers; it assists those who have accumulated money in the proper investment of it so that it will be safe and so that it will grow. The Editor of this Department is an authority on investment matters and he will not only every month give the readers interest- ing and useful information in his articles, but is also ready to aid in personal investment problems. Advice will be gladly given re- as the proper investment of unds and proper plans of saving. Address all your inquiries to Wallace Ames, Financial Editor, POPULAR SCIENCE MONTHLY, 250 Fourth Avenue, New York. Any advertising appearing in this section will 4 carefully in- vestigated by the Publisher of POPULAR SCIENCE MONTHLY. Readers can be sure that com- panies advertising are reliable and that they offer securities which represent sound financial investments. While investments obviously cannot be guaranteed by the Publisher, every effort will be made to insure that only advertisements of absolutely re- liable companies are accepted. ‘Everyone knew that Herbert Clark was going to make good,’’ the Cashier remarked, ‘‘and I have seen him com- ing right along, but I did not realize he was that well off. How did he do it?” “Well, the beginning of Clark’s financial success is ceo right here in our savings department. He opened an account when he drew his first week’s pay—began by saving $5 a week out of his $18. And if you look up the records you will find that every year Herbert increased his weekly say- ings deposit. He increased it as teg- ularly as his salary was increased, These savings were later invested in bonds. It took two years of savings and interest to get the first $1,000of bonds. From that time on he added at least one $1,000 bond a year. By the time he was married eight years ago Herbert had accumulated $10,000 in bonds. He did not save all this out of his salary; interest helped a lot. “CHE YEAR that Herbert was made Assistant Sales Manager he put his savings for that year into a payment ona home. And since then he has used his bond interest to pay on the house. A year or two later his Company gave Herbert a chance to acquire some stock on easy terms and at a very good figure. So for two years he invested in the Company's stock. The stock he paid $8,000 for is worth fully $20,000 now. Of course this was an unusually profitable investment, but the point is that Herbert had the money to take advantage of it when the opportunity came. “Herbert Clark told me today he had figured up that interest and divi- dends on his savings had amounted to over $22,000 in the last fifteen years. His income from stock and bonds is now $3,500 a year.”’ “Clark will be a rich man before long,’’ observed the Cashier. ‘*The money he laid by during the past fif- teen years will fix him so he can take advantage of many opportunities which always come to the man with money. And he has always lived com- fortably in spite of what he has saved.” “WZES, SIR,’’ added Mr. Fowler, “Clark is a fine example of the man who planned his first fifteen busi- ness years in such a way that he is already independent and bids fair to become one of our wealthy men. ‘*Then there is Martin Wood, assist- ant auditor in the same Company with Clark. You remember when Martin moved here from New Eng- land. He wasn’t cut out to be a big executive. But he sure is a true

Page 169

r, 1926 S look very Sav- re ae sed. d in ings 0 of lded cars 000 out ade pe rst 1 he on his to and ck. rth vas nt, the len vi- ed is rte nf- ke ies December, 1926 POPULAR SCIENCE MONTHLY sample of New England stock. Only draws $75 a week today, but his home is bought and paid for, he has a snug savings account for emergencies, $10,- 000 life insurance lena up, 50 building and loan shares fully paid for, and he is now buying first mortgage bonds on $50 monthly payments. He has over $2,000 in bonds already laid away. ‘Martin Wood is the type of man who will always be on a salary, and as he grows old the chances are his personal earnings will decrease. But already he is prepared for that time. His income from savings will more than offset any decline in earnings. The money he has laid away brings in over $700 a year in interest, but nore of this is spent. It goes right back into safe investments, together with $50 a month out of Martin's salary. “The other day I ran across a good plan for a young man. It calls for gradually increased investment, cor- responding to increased earnings. This plan was put out by a house which How Herbert Clark Gained Financial Independence in 15 Years sells 6% mortgage bonds. Here are the figures: ‘$10 a month for 21% years, with interest reinvested amounts to about $325. Then $25 a month for the next 2% years brings the total up to over $1,250. After that $50 a month for 5 years increases the fund to nearly $5,000. Finally $100 a month for 5 years and the investor is worth prac- tically $12,700.”’ ‘I wish more men knew about these figures,’’ said the Cashier. ‘“‘How few men have $12,000 after working fifteen years.”’ “*Yes,’’ concluded Mr. Fowler, ‘‘and how many men could accumulate that much, and more, if they only adopted a fifteen-year plan and stuck to it.” “‘The trouble is, few men look at the business of getting ahead in the right way. Fifteen years seems like such a long time. It is in away. But the average man has thirty-five or forty years in which to work and gain independence. And in fifteen of these years he can put himself in very com- fortable circumstances.” HE booklets reviewed below will assist any investor to get ahead financially. You may obtain any of them, without charge from the issuing house, by writing the Financial Department of Poputar Science Mon uty, 250 Fourth Avenue, New York. For conven- ience ask for them by number as given below. [x] ‘‘How to Buitp an INDEPENDENT INCOME”’ (The F. H. Smith Company) presents a modern way of saving money, explains how first mort- gage bonds may be purchased by monthly depos- its, and presents tables showing results attain- able by carrying out their plan for a period of years. [2] ‘‘DiversiricaTION AND Vicitance”’ (A. B. Leach & Co.) presents a brief analysis of seven basic principles that assure success in the man- agement of personal investments. [3] ‘Increase Your Income 15% to 60%"" (The Adair Realty & Trust Co.) explains how the investor can get 614% on money now earning 4% or 5%, on guaranteed mortgage bonds. [4] ‘‘“Forty-Four Years Witnout Loss to ANY Investor” (S. W. Straus & Co.) presents the safety record of this house and deanthes the safeguards constituting the Straus Plan. [5] ‘‘Sare Bonps ror Investment’ (Halsey, Stuart & Co.) presents their current list of di- versified investment offerings, with instructive investment comment. [6] ‘‘Tae Maxine or a Goop INVESTMENT,” published by the United States Mortgage Bond Company, explains the methods employed by that firm in originating first mortgage bond issues which pay 6% with principal and inter- Booklets Like These Helped Herbert Clark Get Ahead est guaranteed, or 614% without the guarantee, which is optional with the investor. [7] “How to Grow anv Harvest Dottars”’ (CH. O. Stone & Co.) describes a savings-invest- ment plan offered by that Company, and de- scribes how to accumulate from $4,603.25 to $46,032.47 by monthly investment of from $10 to $100. [8] ‘*An INvestMENT INsuRED For Its LireTIME”’ (Mortgage Security Company of America) de- scribes their plan of insured mortgage invest- ments. Nine points of safety are explained. [9] ‘“‘Rures ror Sare InvestmeNts’”’ (Published by American Bond & Mortgage Company) ex- plains in language that the layman can under- stand the émportant factors of safety of real estate bonds. [10] ‘‘Buyinc Bonps sy Max” (A. C. Allyn and Company) explains how the investor may safely and conveniently deal with an investment banker through the mails, and without the usual advantage of direct contact. [11] “Your Money’ (Fidelity Bond and Mort- gage Co.) covers the points of general interest to the investor who is planning to put his money in sound mortgage bond investments. [12] ‘Tue Science or Fortune Buitp1ne,”’ pub- lished by George M. Forman & Company, is the explanation of practical, tested plans em- ployed by investors to attain financial independ- ence. [13] ‘Investors’ Guipe,”’ published by Greene- baum Sons Investment Company, combines a description of “‘bank safeguarded’ bonds with an outline of the service of that company. 211 Different Kinds of Industries St. Louis has factories in 211 different kinds of business. Almostevery line of manufacture is repre- sented. Only eight percent of the city’s industrial force is employed in its largest branch of industry. This wide diversity of industries acts as a con- stant balance and makes St. Louis strong in times of business depression. It assures stability of labor and production. There is a westward trend of industry. Mod- ern business is moving toward the center of the country. This has _ re- sulted in 196 new indus- tries coming to St. Louis in the last six years. The central location of St. Louis makes it an econom- ical distribution point. Your factory in St. Louis would have a distinct ad- vantage over competitors not so favorably located. Send for our booklet “Why St. Louis Grows.” It tells the full story, Address Dept. 32 CHAMBER OF COMMERCE ST.LOUIS, U.S.A. © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 170

POPULAR SCIENCE MONTHLY J HE EXTREMELY sensitive instruments shown in this illus- tration are used to determine with scien- tific accuracy the op- erating characteris- tics of the trickle‘‘A”’ charger under test ? SOLVING YOUR A-BATTERY PROBLEMS with a Trickle Charger ment of radio receiving sets—in themselves capable of consistently reliable and trouble-free operation— should be followed by a concentrated attempt of manufacturers to provide the radio public with accessories that will insure the proper operation of these receivers with a minimum of replacement and attention. For the vacuum tube plate supply, the user now has available the choice of much longer-lived dry batteries, more accurately rated and less trouble- some storage B-batteries, and electric- power adapting devices that very nearly approach the ideal character- istics of batteries without requiring replacement or recharging. The problem of obtaining an equally reliable vacuum tube filament supply seems at this time best solved by aug- menting the storage battery with a continuously charging trickle charger, or with self-contained A-power de- vices that incorporate a low capacity storage battery with some arrange- ment of automatically controlled in- termittent or continuous charger. All of the trickle chargers approved by the Popular Science Institute of Standards should prove very satis- factory in insuring an ever ready A- power supply when used in conjunc- tion with storage batteries and when connected as recommended by their respective manufacturers, because such trickle chargers have been found by Institute laboratory tests to possess— 1. A sufficient charging rate to. pro- vide for all normal filament current consumption. This is essential if the L: IS but natural that the develop- By Cotturns P. Briss, M.A. Director Popular Science Institute of Standards battery is to be kept in fully charged and efficient condition, always—the chief reason for using a charger of the trickle type. | 2. Inherent tapering action or manual control of charging rate to provide against excessive overcharging. As the battery becomes nearly charged, it requires less current to complete the charging and provision must be made for this either by an automatic cutting down of current when the battery reaches a Certain point or by an adjustment that makes possible the controlling of the charging rate. 3. Reasonable efficiency to insure © Popular Science Monthly GUARANTEE The above seal on an advertisement indicates that the products referred to have been approved after test by the Popular Science Institute of Standards. Popucar Science MontHLy guaran- tees every article of merchandise ad- vertised in its columns. Readers who buy products advertised in Poputar Science MontHLy may expect them to give absolute satisfaction under normal and proper use. Our readers in buying these products are guaran- teed this satisfaction by Popurar Science Montoty. THE PuBLisHers economical operation. The ratio be- tween the amount of current consumed by the charger and the amount deliv- ered to the battery must not exceed that fixed by the Popular Science In- stitute as being economical. 4. Zero or negligible leakage when power is off to prevent discharge of battery or failure of power supply or opening connection to charger. 5. Long life of operation elements to insure a minimum of attention. Elec- trodes that are affected by the acid solution or, in the bulb type of charger, tubes that are not long-lived have been the cause of some trickle chargers being disapproved by the Institute. 6. Substantial construction to insure long life and ability to withstand normal abuse. 7. Proper design to minimize fire and electrical hazards. ESTS to determine these seven all- essential points cover several weeks and require elaborate testing equip- ment. The trickle charger is hooked up in the regular way, according to the manufacturer’s instructions. A number of very accurate instruments are then inserted into the circuit to determine both the initial operating characteristics of the charger and its behavior over the entire period of test. Readers who are considering invest- ing in a trickle charger can secure a list of those approved—as well as other radio and tool equipment—by writing to the Popular Science Institute, 250 Fourth Ave., New York, N. Y.

Page 171

De- ed iv- ‘n- en of or to 'C- id of 1€ re id d Ponta TT 'S Phin © ) a) ie Oe oe POPULAR SCIEN CE MONTHLY AUDIO TRANSFORMER If you love music, and want your radio set to reproduce tones fault- lessly, there is one audio transformer you can absolutely depend on—the famous Rauland-Lyric. Voices and instruments alike are amplified with amazing realness by the Rauland-Lyric; with faithful amplification of those ‘‘overtones’’ essential to full, natural reproduction. The amplification curve of the Rauland- Lyric illustrates its outstanding superiority in tone purity. The Rauland-Lyric is the undisputed leader in its field. It is invariably chosen by set builders who want the utmost in perfect tone quality. A new high mark in three-stage audio amplifiers Your receiver’s tone quality depends in large measure on correct audio amplification. The famous Rauland-Lyric Transformer may now be combined with two Rauland-Trios (im- pedance units) to form the Rauland-Lyric-Trio —-the highest known perfection in three-stage audio amplification. Rauland-Trio is a com- pact, well-made unit — containing in one shell — inductance, resistance, and capacity in correctly balanced relation. Write for “Modern Audio Amplification’’ a free book, describing this fine unit. New 1927 Radio Key Book You'll enjoy reading ic—48 pages of interesting, up-to-the-minute facts about radio, simply told. Also full construction details of all leading types of circuits. Send to cents (coin or stamps) to cover postage and mailing cost. ALL-AMERICAN RADIO CORPORATION 4205 Belmont Avenue, Chicago, Illinois © OWNING AND OPERATING STATION WENR “ 266 METERS © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 172

POPULAR SCIENCE MONTHLY December, 193 —_— Colortone Reg. U. S. Pat. Off. Binocular Coils Reg. U. S. Pat. Off. and Low-wave Extension Circuits S-L-F Condenser | Reg.U.S.Pat.Off ti \"'o sd, HAT ideal set you are looking for or contemplate buying— do your tests show that it has been fully developed in Tone Quality ? Extreme Selectivity ? Station Coverage ? Easy, Accurate Tuning ? Simplicity of Control ? Durable Construction ? Test it for these qualities; then test the Synchrophase. Compare. Be exacting. See a Grebe dealer today. Send for Booklet P A. H. Grebe & Co., Inc., 109 West 57th St., New York Factory: Richmond Hill, N. Y. Western Branch: 443 So. San Pedro St., Los Angeles, Cal. This Company owns and operates stations WAHG and WBOQ SGROPEUSE TRADE MARK REG. U.S. PAT. OFF. All Grebe apparatus is covered by patents iD} i) granted and pending. TRADE MARK REGUS PAT OFF The Synchro. phase is also supplied with battery base and in five beautiful con- sole models. ‘**Make conscien- tiousness and sincerity your first principles.” — Confucius. These are the principles be- hind the success of the Synchro- phase. Diier ue & = This seal on a radio, tool or oil. burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. = |

Page 173

POPULAR SCIENCE MONTHLY ITH the FERGUSON Model Twelve you enjoy absolute fidelity of tone. The rendition in the ; distant studio reaches your living room round, full, clear—with all of the original expression of the artists. When an orchestra plays, you hear all of the notes both treble and bass —the harmony of the whole. The music rests and soothes you— as it should — because the true tone colors; all of the countless delicate shadings and overtones; reach you unaltered —in perfect timbre! The nearest Authorized FERGUSON Dealer will be glad to let you hear how enjoyable radio can be. J. B. FERGUSON, INC., 225 West 57th St., New York, N.Y. te . ‘Sri dvare : San Model Twelve —a precision-built 6-tube / FERGUSON, with superb cabinet of ISS graceful lines, $75. (Ten per cent higher West of the Rockies.) ‘The Gold Standard of Radio Rec $5 Su —— Or NO Bee ee ee AO Cao v “aS 9 ¢ qs A = 9 vers BaD BB EOE. Ne eZ ms AES The Two Tuning Dials Light when the Receiver is in operation, Complete shielding gives this Receiver its Marked Selec- tivity. No Seasonal Models— Continually Develop- ing Refinements © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS, See page 6.

Page 174

POPULAR SCIENCE MONTHLY A Christmas tip from ee at any fine piece of carpentry work. The finish comes largely from the skill of the carpenter, of course. But there’s something else. Look into his kit. You’ll see not only an adequate number of tools, but find them all fine tools, many carrying the Stanley name. Right there is a Christmas tip from the carpenter—a chest of Stanley Tools this year for some man or boy! A fine assortment of tools, and all good tools— the right set for repair work or the mak- ing of such things as book cases, dog houses, and other useful articles. The sturdy oak chest keeps the tools safe and handy. A Stanley Tool Chest is a complete gift. You will find Stanley Tool sets at a wide range of prices and in a wide December, = No. 907 Tool Chest No. 902 Tool Chest variety of assortments—from No. 904 with 12 tools in a fine oak chest at $15, to No. 850 with 49 tools in a beautiful cabinet at $95. There are also assortments of the same Stanley Tools in cardboard dis- play boxes with simple directions from which the recipient can make his own chest. There are several of these ‘‘ Make Your Own Chest”’ assort- ments, at prices from $5 to $20. There’s a Stanley Tool Set to fit every pocket-book! ‘Ask your hardware dealer to show you the line of Stanley Tools. And send for our Catalogue No. 34-E which de- scribes Stanley Tools both separately and in assortments. Address: The Stanley Works, New Britain, Conn. The best tools are the cheapest to use Ask your hardware dealer © the carpenter oes SC STANLEY TOOLS © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6.

Page 175

POPULAR SCIENCE MONTHLY This 84 Page Send For It WONDER BOOK MAIL ORDER HOUSE IN THE WORLD. OVER 2000 ITEMS From the most beautiful, fully equipped console radio set, Includes the following well known circuits, the smallest part or tool for the set builder—kits, * ar nosh supplies of every conceivable type and style. 5, 6, 7 designed and tnd 8.tube sets, with three dial, two dial, and the newest and most radio engineers: Madison Moore Super; most popular single simplified control. Allsets are assembled WVictoreen Super: Silver Marshal Six; Sar- in beautiful, genuine mahogany and walnut cabinets in a > ice of latest types and designs. gent’s Infradyne; Remler Super; Short Wave — 7 ; Kits; 9-in-Line Super; New Acme Reflex; A complete line of “B” batteries, eliminators, including the Cockaday; Neutrodyne; Browning-Drake; all famous Raytheon Eliminators; latest types loud speakers, famowpeakers, “A” power units. Everything in radio at classes of radio frequency. Super Heterodyne money saving prices. and every other approved popular circuit. The New Ampliphonic Six The Latest Two-Dial Receiver WITH THE Genuine Amplion Unit Genuine dark tone and shaded walnut cabinet. Stands 39 in. high. Top nators, etc., everything concealed sitely designed radio cabinet. 6-tube tuned radio frequenc tube and an additional tap for straight line condensers. Wonderf ket at more than twice the price. You must have this latest guide to Radio prices and Radio quality. Allof our vast resources and radio experience have been utilized to assemble for you in one gigantic institution, the best and newest things in radio. The Randolph catalog is indeed the radio market place of the world—a masterpiece of merchandising that befits our house—THE LARGEST EXCLUSIVE RADIO Radio Bargains measures 27x16 in. Beautifully etched burl walnut anels. Built-in loud speaker with Amplion unit. arge doors open to smaller doors enclosing a large compartment for batteries, chargers, elimi- 6 Tube Tuned Radio Frequency two dial con- trol receiver. 3 stages of direct and trans former amplification. Has provision for power battery voltage. Very latest construction in- cluding solenoid coils, bakelite sockets taking all the latest X-type tubes, modified uS°7@so - volume, nothing like it on the’ mar- RADIO KITS approved by the world’s fore- We Save You Money because we handle radio exclusively and sell a tre- mendous volume of every- thing in Radio. Volume purchases reg- ulate prices. We command rock bottom prices from manufacturers, and in many cases we contract for entire factory output of exclu- sive products. You will benefit by our great volume of pur- chases and sales, by securing anything you may want in radio at a substantial saving. in this exqui- increased “B” Without Accessories Symphonic Five Brown Spanish leatheroid finish cabinet with gold engraved walnut panel to match. Contrasted beautifully with the black fine tuning knobs. Two small knobs control volume and clarity. The volume control is of the finest smooth slow variation type. Roller bearing. Condensers are of the modified straight line frequency type, sub- These sets are typical examples of the bargains in eur catalog. You may order direct from this page, sending P. O. money order or draft for full amount. We ship freight or express, charges collect. We guarantee te back up every article with our own, as well as manufacturer’s, assurance of quality. stantially constructed and of latest design. All is sub-panel mounted, using the new X-type socket. Latest development in solenoid coils. Two stages of low ratio audio amplification with high grade transformer offers the true amplification re- quired for both low and high notes. $249° Without Accessories The set complete with five t X201A tubes, two 45 volt “B”’ batteries, one 100 Amp. Hr. storage battery, complete aerial equipment, one battery cable attached, including cone speaker o f the same type as $54.75 pictured .. . ColumbiaGrand 6-Tube Console Set Columbia Senior Six Beautiful table set. New localized control. One hand to tune with, three rotating drums easily controlled and easily logged. Dark finish etched panel mahogany finished hand-rubbed cabinet. Size 7x22. 6-tube set, giving tremendous volume, wonderful tone quality, latest straight line condensers, solenoid coils; sub-base mounting and new am- plification. Designed to sell for over 100.00. Price, § 50 without accessories Set complete with two 45 volt “B” batteries, 100 amp. hr. Storage ‘‘A” battery, one 4% volt “‘C” battery, six type X201A tubes, complete aerial kit, attached battery cable, quality cone speaker or Victor horn type loud $ 45 ere This set with all ies which incl Here’s a sensational bargain in a console radio with built-in — loud speaker and adjustable unit. Spacious compartment for all batteries, etc. Very latest type 6 tube tuned radio fre- quency receiver. Low loss modified straight line frequency condensers. Has three stages of low ratio audio ae: Designed to accommodate new power tube. ptt Ste th X-ty sockets. Beautiful gold etched panel with handsomely $42 § engraved designs. Price of set with accessories........ ae eae —— —— ee This Coupon Brings. t Great RADIO Book FRE RANDOLPH RADIO CORPORATION Beautiful hand rubbed, two-toned mahogany finished cabinet, size 18x19x36. Built-in COUPON NOW. Randolph Radio Corporation 180 North Union Avenue - Dept.185 - de 2 45 volt ‘““B’”’ batteries, Amp. Hr. storage ‘‘A’’ battery, 6 201A tubes, aerial and ground equipment—everything complete, nothing else $65, 95 to buy ° You Must Have This Book Space limitations here prevent our telling you more about the Randolph Catalog. Simply fill out and mail the coupon—or you may send a postal or letter—and this truly remarkable Radio loud speaker. book will come to you ABSOLUTEL REE.. MAIL THE © This seal on a radio. tool, or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See page 6. 180 N. Union Ave., Dept. 185 Chicago, Illinois Send me—free—your 84-page, 1927 Radio Book. Name Street and No. R.F.D. Bor “ide dcndsenduncescesedesusetedueneeussoqnadenasesenaeeaele City State___ Chicago, Il.

Page 176

168 POPULAR SCIENCE MONTHLY December, 7: STRFEINYOURHOME Sars

gut —_c F Send Coupon for = allt the very first to engage = proposition. man re of radio sets, and to us t is ev y nols ine--that' one ne of the rel the cael ant and steady expansion of their business which we have > ae other sets have observed year after year. We are personally acquainted with all officers superior per= 50 to $250 each but M of the Corporation and from experiences know them tobe men of honor. formance an the M b vphadetations stionsal sooo and s a We consider them to oe a Pty and — Miraco Radio a . icy and Havana, Cale apy time dealings” THE PROVIDENT SAVINGS BANE & TRUST CO. = Nacogdoches, Texas. Onmy Miraco | tey are on the alr. Alex Member Federal Reserve System. Capital and Surplus over $3,000,000 Sricss, coal 1 nave heard ‘stations from Gaba, to BaATe CestuEn sets seTs yt Pioneer Set Builders them easy to to Pittsburgh. Walter M Frisble.” | have siven Mirace a thoroug Midwest Radio Corporation ith Successful Year ean cell Sendcoa- mieenesitas| Eee || All theProof you want is waiting forYoul BL = over Mey coast to : n, En the p> yp 7 le Cuban tod Mexican stations _ Coupon or bay brings 1 reports from hosts of ~o in your. tangy 4 Bee Longe ayn proving that b ight-- BM | Others town ts at ro jactory ° st experience fan _. at ptm ee code ng up to four a as ng vou can alse! oon he ers, re) N ng aradio. 7 , batter savings pight we got WIAK mare fubeatsotdy el car proposition ‘bolesd epondin 70 CORPORATE andKFiLog ——, Puller Temple.’ money ray nthe pay es of Sets Cincinnati, O- : MIRACO OUTe OFFER IS] : renee as sus geee ht oot St. — of users er oan — MMiraco ayo literature, testinetSctory vores we ties gation, 8¢ bi ent all ee ei SW! Sige seend, our Htiraco te boot tea fal parcels ars of your applies. ) Ag -iam ) ies 00 ia ie epee omen Ane and | ") pa Paces better Get jote of distant NAME or

ane t t susp msching: . Tison. a ADDRESS niin jurely am |. Orvey © This seal on a radio, tool or oil burner advertisement signifies the approval of the INSTITUTE OF STANDARDS. See Page 6.

R. R. DONNELLEY & SONS CO.. CHICAGO

Page 177

hestertiel CIGARETTES ‘Such popularity must be deserved © Liccett & Myers Tosacco Co

Page 178

Wren the Thanksgiving feast is spread—and gay friends gather when you're joyously thankful for another year of health and plenty —have a Camel! Camels represent the utmost in cigarette quality. The choicest of Turkish and Domestic tobaccos are blended into Camels by master blenders and the finest of French cigarette paper is made especially for them. No other cigarette is like Camels. They are the overwhelming choice of experienced smokers. © 1926 WHEN it’s Thanksgiving. And your chosen friends are enjoying the good things of earth—have a Camel! For no other cigarette ever gave so much added enjoyment to a Thanksgiv- ing feast. No other was ever so welcome to your friends. Millions of experi- enced smokers are thankful each day for Camels. This distinctive cigarette brought the world a new measure of smoking satisfaction and contentment, for Camels never tire the taste or leave a cigaretty after-taste. Be- fore Camel it was impossible to get every good feature in one cigarette. So this festive day, with thanks for the good year that is gone—send up the fragrant smoke that is loved by millions. On Thanksgiv- ing Day have the best. Have a Camel! Our highest wish, if you do not yet know and enjoy Camel quality, is that you may try them. We invite you to com- pare Camels with any cigarette made at any price. R. J. Reynolds Tobacco Company Winston-Salem, N. C.

Page 179