Popular Science Monthly 1923-03: Vol 102 Iss 3

Page 1

FB? 1923 PERIODICAL, ROOM UNIV. OF MICH, pene Most Wonderfully Illustrated Magazine in the World seneka:. Livrary Beginning “The Story of Man and His World” faRcH —— How to Drive Your Car Like an Expert ("%°) ' 43 25 CENTS | — a tha FE i SIR ERIE Sig RT EE BORER ER ae eee ee hes Sn 7 ~

Page 2

Your selection of Starrett Tools does you credit. I’m always glad to see a youngster start off the Starrett way—it’s the right way. I’ve seen a lot of them start in my day and those that stick and “Aer nee are the ones who've got the tools to handle every ob right. it of the “crack” men in the metal working trades.will tell you the same thing—some of them right in our own shop have been living with Starrett Tools for forty years now. They know it pays to own the best. Starrett Catalog No. 22W describing over 2100 fine precision tools free on request. Write also for the Supplement, showing the newest tools used in the best shop practice. Youre on the right track- son. THE L. S. STARRETT CO. The World’ s Greatest Toolmakers— Manufacturers of Hacksaws Unexcelled ATHOL, MASS. J Z Oo ea (WY 4 rs Md AWS oO LY N Yankee One Inch Micrometer U: St la | eit To 1} For MB as. ig: one up to se Starre ols 2 ¢ Be 4811 one inch. Frame is made of drop forged steel, nickel plated, dull finish. Has im- proved speeded screw with means for ad- justing to compensate for wear. An unus- : ually accurate “‘mike’’ at a most attractive price. Popula

Page 3

Popular Science Monthly People express themselves in their possessions. Not by the cost but by the merit of those possessions. Victrola No. 130 $350 Victrola No. 130, electric, $390 Mahogany or oak Other styles $25 to $1500 AVictrola — == REG US Pad OF HIS MASTER'S VOICE” 7 Important: Look for these trade-marks. Under the lid. On the label. Victor Talking Machine Company, Camden, New Jers-

Page 4

Q Popular Science Monthly POPULAR SCIENCE MONTHLY MARCH, 1923; Vol. 102, No. 3 Published in New York City at 25 cents a Copy; 225 West Thirty-ninth Street Mar $2.50 a Year In This Issue—A Great New Serial and 100 Articles, Including: ar ; : : Page Page F A Millionaire Radio Fan’s Hobby................ 24 Mysterious Birthplace of Eels Discovered........ 50 B : Jism New Low Voltage Tubes for Radio Sets........... 53 The Story of Man and His World................ 27 , a , iiaiisiiesd: i iataibiinbias ome ental A Trip to the Arctic in a Flying Boat....... aes 59 By E. E. Free Science Opens Wonder Caves to Tourists.......... 60 Record Glider Revives Langley’s Design.......... 33 Will Women ' ile: Bin Mens Ceamee? 63 Upside Down Exercises to Keep You Fit.......... 39 How New Chicago Post Office Keeps Mail Moving 66 Secrets of Successful Auto Driving.............. 43 By Harold F. Blanchard Suspended Railways May Bridge Cities The Home Workshop—page 77 Novel Inventions for the Household.............. Better Shop Methods—page 82 A Foretaste of Features in Our Next Issue tories a small band of American scientists are laboring desperately to wrest a marvelous natural secret from the green plants around us—a secret that may help us avert a threatening world-wide fuel famine. These men—among them being dis- tinguished members of the American Association for the Advancement of Science—believe that today we are consuming our oil, coal, and wood at a rate that means early exhaustion of the world’s supply. ‘‘And then what will happen?” they ask. Civilization would totter, they believe, unless a new source of energy could be found. To find this energy they are turning to the sunlight. For it is really only the stored-up energy of the sun that we use when we burn coal or oil. There- fore, we must find out how coal was made, and to do this we must discover how living plants use sunshine to form the material that was laid down, ages ago, in the form of the coal we mine today. This secret of trapping the sun’s energies is still locked up impenetrably in the green leaves of common plants. The fascinating story of how science is striving to learn this secret will be told in the next issue of PoPpu- LAR SCIENCE MONTHLY. [: THE seclusion of their labora- “If you can keep your neck and abdomen strong, you can safely be guaranteed a 50 per cent longer life than the average man.’ So writes Dr. C. Ward Crampton, noted health expert, who prescribes the above ‘‘star gazer” exercise as one of a novel series to promote longer life. See our next issue aide to Secretary of War Weeks, in his nation-wide campaign for better American manhood, will tell in the next issue of POPULAR SCIENCE MONTHLY what your physical shortcomings are and just what kind of exercise you should practise to remedy them. Scholar, machinist, laborer, and bank president—Doctor Crampton holds up the mirror to each and shows just what correcting recrea- tion and exercises he requires. DRY cell vacuum tube radio set for $20! Six months ago this sum would have bought you a small crys- tal receiving set; in the next issue of POPULAR SCIENCE MONTHLY our staff radio expert tells you how to assemble at the same cost a set that will receive from four to five times as far as the average crystal set. You would have to spend $60 or more for an assembled set of equal efficiency. An accompanying article describes a novel three-stage vacuum tube set, using power tube amplifiers, which was built to obtain maximum loudspeaker results. AROLD F. BLANCHARD, staff automobile expert, has prepared a money-saving article for the April POPULAR SCIENCE MONTHLY, telling of the simple tests every motorist can apply to his car to determine what repairs and adjustments are needed in preparation for summer driving. : OZENS of other fea- O YOU need exercise? Of course you do; but do you know that there are three distinct classes of exercise and that your particular “exercise diet”’ should be prescribed by an expert just as care- fully as medicine? Dr. C. Ward Crampton, POPULAR SCIENCE MONTHLY Issued monthly. Single copy, 25 cents. Yearly subscription to United States, its possessions, and Canada, $2.50; foreign countries, $3. Entered as second-class matter Dec. 28, 1918, at the Post Office at New York under the act of March Pa 1879. Entered as second-class matter at the Post Office Department, Canada. Printed in U. S. A. Copyright, 1923, bythe Modern Publishing Co. The contents of this magazine must not be reprinted without permission. H. J. Fisher, President; R. C. Wilson, Vice-President O. B. Capen, Secretary and Treasurer ture stories—informa- tive, entertaining, money- saving — will make the next issue of POPULAR SCIENCE MONTHLY fhe most interesting publica- tion of the month. On newsstands every- where March ninth ART COLOR PRINTING CO., NEW YORE

Page 5

ithly = _| ¥ ° 5° Page There never was _a writer with the com- the wilderness, the scent of crisp air, the James Oliver Curwood at an_ unprece- aged wer of James Oliver Curwood. overpowering sensation of great, untram- dented price! At last this world-famous is have that gripping, broad in- meled spaces. author is brought within the reach terest of big things done in a big way. Here are the humor and tragedy, the everybody. By acting quickly—that is the Whether you read about “Baree, of grief and gladness of a ay and glorious condition, remember—you can obtain a Kazan,” the story of the little outcast country. ore than 2,000,000 copies of | wonderful six-volume set of James Oliver well Seg. or about “The Hunted Wo- these books have been sold. The tales Curwood for practically half price! man” the appeal fairly takes you by the have been eagerly sought by moving pic- set, which is beautifully bound in dark heart. You find yourself gripped by this ture companies. : maroon cloth, with the titles lettered in gat writer’s power. As no man has done And now you have the opportunity of gold, has sold regularity for almost DOUBLE fore, he brings to you the atmosphere obtaining a beautiful six-volume set of the present price of the North, the appeal and mystery of James Oliver Curwood used to sleep with a young grizzly bear, and asa result of this clos ‘ study his novel ‘‘The Grizzly King’’ is one of the most en- trancing and realistic animal stories ever written March, 1923 From the Great White Way to the Great White Spaces Get away from the grind of your daily routine. James Oliver Curwood is waiting to take you, while you sit in your easy chair, to the magic outdoors of the great Northwest, where interesting adventures make your blood run fast. This great author ‘knows the animals of the wilderness more intimately than any other writer. His absorbing tales of their adventurous life are laid in the range of country where no hunters go., Pack up your troubles and follow CURWOOD into Adventureland Cr to the great magic land of the __ wilderness! You do not have to stir out , as a Northwest — come where the _ of your easy chair to do it. 8 a breath of Romance stirs in the blood of James Oliver Curwood takes you to ne. St: ee Es poy men and women—come to the land of | the North Country, where splendid ad- BAB pts at : | adventure, strange, enchanting, won- ventures are always happening—where drous. Stand under the great open sky romance steadily spins her golden web —gaze at the wondrous Red Moonand__ of enchantment. Here is great drama, the North Star—hear the cry of the played by great and fearless men who wolf pack—thrill to the magic of the quicken your red blood and lift you forests—sit by the soft glow of the clear of care and worry, carrying camp-fire—come tothe top of the world you far and happily into Adventure- and feel the spell of the vast white land! 6 Complete Novels—James Oliver Curwood Now at a Special Price “The Hunted Woman,” ‘“‘Baree, Son of Kazan,’’ ‘‘God’s Country and the Woman,”’ “The Grizzly King,’’ ‘‘The Courage of Marge O’Doone,’’ ‘‘Nomads of the North.” If you are tired of ordinary nove ¢ > if you are “fed up” with the ag , 4 ~ drum of your daily routine, if ¢ — you want to feel the clean a white snow of the great . sf yy, . Northwest under your » feet, if you want to live among real men and real women. follow Curwood into ad- , ventureland. Don't bother to send any money. Mereiy mail the coupon and , 4 the six volumes of Curwood will be sent to you at once. When they arrive # m you have the privilege of examining ¢ Nelson them for seven days, and then paying for them in smal] monthly install- ments. This offer is good only while the present special edition is available. Take advantage of it now—mail the coupon at once and make sure of your set. Dept. C-363 Garden City, N. Y. > Kindly send me the ° six- volume beautifully : bound set of James Oliver ” Nelson Doubleday, Ine. 4 Curwood at the special low i Dept. C-363 4 price, for free examination. I Garden City @ will either return the books at A fe) your expense in 7 days or send 43 you $1.50 and then $2.00 a month . © _ for three months, making a total of © only $7.50. By sending cash with your order you ca secre this set for only . RI cy R ee rh OO OM 25 Prom: fem gk ah ni arson a ment ee ee ee | |

Page 6

Popular Science Monthly Read the World’s Most Amazing Story DOO OPOOMOVO OOOO A CLOOUD MMOL MLL AOL OLY | | e it HIS slinking, fear-ridden, half-human creature, emerging from the black ~~ night of time toward the dawn of civilization, was your first ancestor—the ape-man, whose story you will read in coming issues of POPULAR SCIENCE MONTHLY. Millions of years ago he skulked ‘through the forests of what we now call Asia. He dwelt always in a black fog of fear. He was in terror of the savage beasts around him, of the hail and lightning and thunder; of Z g a MUI LL dedecddddcdddddcdedeedeedlecdedeeededecceecdecddeectecdlecddleddcdddccdhddddcddccddddddea ~ { ; oak r A, Lan the cold and darkness. He was dwarfed by all the menacing powers of nature. He was only a trembling experiment. He might have been utterly stamped out— and with him would have vanished - the promise of our human race to come. But two things saved him: He had hands with which to clutch stones as weapons, and within his savage skull there was the glim- mer of a mind. How this creature developed a real brain and a human form; how he learned to in- You owe it to yourself not to miss a Mee cdc dededddddeaddddeddeeddeadddddeddteeccdeddeedeeddedesacdhddddddddddddmmmyyys§ WMA | SQN WMMMb UMM Wl WT LEELA Cee ee Li Mg dddddde MULL lll MULL MLO UDAP LAL From model by Dwight Franklin vent tools, to hunt in bands, to kindle fires and build a hut, to tame wild animals and plant grain—these great discoveries of science are told in the most fascinating serial ever published. It is “The Story of Man and His World,” by Dr. E. E. Free, beginning in this issue of POPULAR SCIENCE MONTHLY, to run throughout the year. It will show you a breathless panorama of man’s conquest of nature, and of the great fundamentals of science that everybody wants to know. single instalment

Page 7

of 1g of in of

March, 1928

: AID. Bees ems TU AA > 2ee \®@ «4

xx

Men of the Hour in Science and Discovery Makers of Tomorrow Probes Life Secrets NE of the world’s most famous desert explorers, Dr. D. T. MacDougal, general secre- tary of the American Association for the Advancement of Science and a tireless worker in the field of botany, has actually succeeded in devising an artificial cell that behaves much like the living cells of plants. ~ y means of remarkable appa- ratus shown above he is able to simulate many properties of living protoplasm, such as the process by which living plant cells absorb food materials.

Teaching Us to Travel by Air Comrie arrangermcnts for a 5000-mile air trip to the Arctic Circle in a palatial flying boat, Charles F. Redden hopes to confirm further his belief in the practicability of long distance com- mercial aviation in America—a belief that induced him to organize the Aeromarine Airways, Inc. Instead of merely talking about a “glorious future for commercial aviation,” Redden set out to make a record in aerial transportation. In the second year of operation, his company carried 9107 passengers 739,047 passenger miles without a mishap. His proposed journey to the Arctic is the first step to establish . regular aeromarine service tween New York City and the Far North. With him will go half a dozen businessmen-sportsmen bent on an arctic hunting expedition. Plans for the voyage are de- scribed on page 59 of this issue. Close-Ups of Some of the

I thousands of strange fossils that are giving us amazing new knowledge of life on earth in prehistoric times, making it possible for science to piece together, bit by

Luther Burbank Kare best loved and most pic- turesque of America’s great scientists this month rounds out his fiftieth year of labor in plant wizardry—an event that is being celebrated by California, his home state. During half a _ century of achievement, Luther Burbank has evolved more new species of valu- able plants than any other man. In next month’s issue he will tell in his own words the fascinat- ing story of his life work and of his dream, at the age of 74, of apply- ing the laws of plant raising to creating better humans. A Famous Young Explorer N LONG and hazardous exploration trips through Chiria, Roy Chapman Andrews (at left) has collected bit, the world’s history. This young scientist of the American Museum of Natural History (who incidentally is one of the world’s leading authorities on whales) has explored Alaska, the Dutch East Indies, Borneo, Asia, and right now is in Peking, preparing for his third expedi- ‘ tion through the Gobi Desert of China, where he has discovered the remains of giant reptiles and what scientists believe to be the first mammals.

»ee« LS. < eS wee — ee 4 =o = Pees

Page 8

Popular Science Monthly = : + Be 4 tae hohpiness or Ct amuty 1 15 chout t tn come, said Confucius ,“itcan be known _ be forehend. jnsure complete, = radio happiness v vith : ) SONG RE O 2 AEC

Page 9

hly

March, 1923 25 Waterfall Plunges from Power Plant “Safety Valve” ‘sowins a great stream of water

the surge chamber, and from there directly into two pen- stocks 1370 feet long. The flow is governed by two butter- flowing through a mountain tunnel nearly two miles long, then rushing with tremendous force through 15-foot pen- stocks, or power house supply conduits, at fly valves, 10 feet nine inches the rate of 1800 cubic feet a second. in diameter, said to be the What would happen if valves in the pen- _largest in the world. stocks were suddenly closed, causing this When it is necessary to great body of surging water to gather its divert the water from the full force and strike a terrific blow, like plant, these valves are closed, some gigantic sledge hammer, against the the surge chambers overflow, walls of the conduits? and the water is diverted to That is the problem that confronted en- one side, plunging over a pre- gineers in constructing the Pitt River power cipitous cliff to the bed of the plant, which supplies the San Francisco river 400 feet below. Bay region in California. By experiment- This plant is but one unit in ing with miniature models, they learned a gigantic power development that to prevent the pipe lines from bursting _ project which, when completed, under hammer blows from sudden changes is expected to have 600,000 in pressure within the pipe, they would horsepower capacity. require a chamber 60 feet in diameter and 55 feet deep to take off the surge, or massing of waters. Such a surge chamber they built at the penstock end of the 10,111-foot tunnel. At normal times, water flows from the tunnel through

nT WATER

PLUNGING over a precipitous cliff to the river 400 feet below, this pic- turesque waterfall represents a tremendous force of excess waters from the Pitt River power plant, Calif.—a surging mass that, if suddenly arrested in the penstocks by the closing of valves, would act as a gigantic sledge hammer, breaking the pipes i bingncn seething water flows from a surge chamber—the safety valve of the power plant —stationed at the head of the penstocks and at the end of a two- mile supply tunnel through a mountain, as shown in central diagram. When pen- stock valves are closed, the surge chamber overflows, the overflow being diverted over the cliff as shown above The photograph at the left shows the magnificent Pitt River power house. Compressed Air Shoots Round Bullets from High Power Rifle

MMUNITION costs for hunters may be greatly reduced through the in- vention of a high power pneumatic rifle by A. V. Dickey, of Seattle, Wash. The gun uses compressed air under 600 pounds pressure and is said to have a muzzle velocity of 200 feet a second greater than that of the ordinary small caliber powder rifle. carrying one of these bullets into the gun chamber. Pulling the trigger releases a hammer that strikes a firing pin attached to the air release valve. The instant the valve re- mains open is sufficient to allow a quantity of air under a pressure of 600 pounds to escape, forcing out the bullet.

es ee Ee a AY 6 See te, BR EE raver fof 8 ey ye a ge

7 ne geet A lever attached beneath the rifle is connected with an air FOLLOWER PRESSES BULLETS INTO ROTARY DRUM DRUM CARRIES CHAMBER

COMPRESSED

J . AIR CHAMBER pump. This lever is moved back and forth until sufficient pres- wr tained in the air reser- voir in the stock. Spherical _ bullets are then insertedina [eZ chamber behind the pease breach, a cocking slide on the right side “ Ingenious is moved forward, of compres

sure has been ob- es) P| - - - -

BULLETS TO CHAMBER ~~ FIRING PIN <i ae wm me a Brees riRiNe TRIGGER PIN TO OPEN RELEASES VALVE HAMMER zi CATCH of ration A air gun

The operator pumps air into a reservoir in the stock of this high wered pneumatic rifle. Spherical ullets are inserted, and the trig- ger, when pulled, opens a valve, releasing enough compressed air to drive out the bullet at high velocity

Page 10

26 Porous Concrete “Boards” Are Fastened by Nails WELT EAN Popular Science Monthly Nailed to wooden studding, porous concrete slabs an inch thick form the walls of this attractive garage. The structure of the material is shown in the actual extremely light in weight yet strong enough to withstand a crushing pressure of 600 pounds to the square inch have been developed recently by a New Jersey manufacturer. Reinforced by wire netting, these con- Tie porous concrete slabs that are size cross section at the left After about 24 hours of steam treatment that removes all traces of the chemical, the slabs are in a porous state. At this point they are cooled and placed in a steam curing room, where they are kept heated and moistened for two or three days until they crete boards, only an inch thick, can be possess the strength necessary for building operations. When used in connection with stucco fin- ish, the siding slabs are nailed to wooden studs with the wire mesh reinforcement out- ward. This makes a good base for the stucco. nailed to studding much as lumber would be. Because of their peculiar air-cell structure, they are said to be exceptionally effective heat and sound insulators; while their resistance to heat, steam, or water, it is claimed, make them comparatively fire- proof. Mixed with Wax-like Pellets In manufacturing the slabs, cement and sand are mixed with a specified quantity of small pellets of a secret chemical composi- tion resembling paraffin wax. After water is added, the cement, sand, and pellets are mixed thoroughly, then poured into a steel form over wire netting reinforcement. As soon as the cement has set, the slabs are removed from the forms, placed on steel cars and hauled to a steam tank where, under the action of exhaust steam, they are heated rapidly. This heat melts the waxlike pellets, which drip out of the slabs into receptacles beneath the steam tank. Se ‘SOPNDING LAPPARATUS ne WEIGHT CARRIES APPARATPS TO'ROTTOmM ~~ The brass pipe sounding apparatus, Depth is determined by measuring with weight attached to sink it rise of water in glass tube Carried in cars to a steam tank, in background, the unfinished slabs are subjected to heat that melts the waxlike pellets, producing pores Water Pressure in Tube Measures Depth of Soundings N INGENIOUS sounding _instru- A ment now in general use consists of a brass pipe inclosing an air-filled glass tube and a lead weight that carries the instrument to the bottom of the body of water where soundings are to be made. Depths are determined by noting the ex- tent to which water pressure compresses the air in the glass tube. The tube is open at the lower end, while the inside surface is covered with a water soluble dye. The in- strument is suspended from a thin wire. The water pressure at any depth is pro- portional to that depth; hence, as the in- strument tube sinks, the water entering the brass pipe rises higher and higher in the tube, dissolving the dye as it rises. When the instrument is raised, the depth of the sounding is determined by measuring, on a scale graduated in fathoms, the extent of the tube that is free from dye. March,

Page 11

thly

fin- den ut- C0.

March, 1923 “27 The Story of Man and His World Beginning the Most Fascinating Serial of Science Ever Published

R. E. E. FREE, America’s best writer of popular science, begins herewith a wonderful series of articles on the secrets of life and mysteries of evolution. He tells the story of how the Life Force first took shape in the sea, a billion years ago; of how it rew into countless strange new forms; of how worms, izards, reptiles, and apelike creatures each in turn inherited the flame of life and passed it on to still higher animals; of how finally Man himself emerged. - And Doctor Free tells not only the Story of Life, but E. E. Free, Ph.D., the Story of Science, by which we have learned Life's

Ro: scientist, engineer, H lis h h read Nature’ ict = secrets. He tells how men have ature’s picture- oT couilt eaeaee writing in the rocks, explored the heavens, probed the Especially Written By Dr. E. E. Free for Popular Science Monthly Prepared with the co-operation of some of the world’s leading scientists secrets of invisible atoms, discovered queer animals in far corners of the globe, and finally pieced all these clues together into one majestic drama of the ages. Behind this drama some may see moving a Divine Plan of things; others simply the thrilling work of blind chance; but none can fail to be inspired to awe by the natural wonders so vividly presented in Doctor Free's straightforward narrative of fact. Thanks to the co-operation of many eminent scien- tists whose help Doctor Free has had in preparing each article, the most amazing recent discoveries of science are now put within reach of the average busy man for the first time.—Tue Epiror.

First Article: The Dawn of Life What Your Body Is Made Of E KNOW today that the earth is The Story Told very old, older by millions of in Pictures years than the scientists of twenty years ago would have believed possible. We now know that the great drama of life on earth, the drama in which you and I are playing our little parts, has been going on for more than a billion years. Think what this means. A period so in-

; 24 LBS. OF comprehensibly long that a man’s whole 685A. lifetime is but a few seconds in comparison! -COAL (CARBON) Yet step by step back into this tremen- ; dous abyss of time we are now able to trace ty the evolution of man, the story of how OF every living thing in the world developed IRON out of tiny life germs first born in the sea some thousand million years ago. Suppose you could have been present then—what would you have seen? In pools along the margin of the sea you might have discovered a speck or two of transparent jelly; here and there on the surface a little scum of slime. You would not have recognized them for living things alone. ; Behind the seashore rose smoke-crowned volcanoes. Against the barren cliffs surged storm waves of the primeval sea. Earth- quakes rocked the land. Lightnings

flashed; thunders rumbled; down over the Yeoz OF _——— rocks there poured the floods of rain. SETRD SUGAR And in the midst of all these natural - wonders the greatest of them all would have gone unnoticed. ‘For the greatest of them, } —_ the most significant, the most important SALT in earth history, were undoubtedly just those small slimy specks washing about in the seashore pools. These slime specks, or something very like them, became the parents of every RY OE

living thing on earth. They were the first i ancestors of man. 6O CU. FT. Where these first living particles came NITROGEN, HYDROGEN The human _ body grows from a single egg cell, such as that IODINE shown highly mag- IVALENT nified at left. . Less TO Vio OF ONE than a hundredth of DROP OF an inch in diameter, TINCT. OF IODINE it can produce an adult man com of perpen of sep- arate tissues and containing all the AND ABOUT 10 0Z. OF OTHER ELEMENTS,|INCLUDING POTASSIUM chemical elements 4 illustrated at right FIDORINE: SULDHUR,AND MAGNESIV

PENG. ce eno Dp, Pas The Same Story in es coma? Percentages

This picture illus- trates what you would get if you ana- lyzed the ‘‘contente” of an average man. These chemical cone stituents of the nor- mal human body have a market value of about 98 cente! The column below shows the percent- ages by weight of the elements mak- ing up the various tissues, while on the opposite side of the picture are shown the normal quanti- ties of each sub- stance. Note that the body is mostly composed of water 66% WATER

~~ 3.1 MS NITROGEN —~<— 2:F% HYDROGEN ~<— 15.8 % CARBON

am) —~<— 2.5 Yo CALCIUM pany <— 2% PHOSPHORUS ] —<— 6.7% OXYGEN Besides the above elements the body contains minute quantities of salt, sugar, potassium, iron sulphur, ma and

4 um, fluorine, totaling a fraction over four tenths of one per cent.

seinpecnncencaae tense tienen ea “s ~ =" = be

Page 12

26 Popular Science Monthly Porous Concrete * ‘Boards” Are F astened by Nails SRA Nailed to wooden studding, porous concrete slabs an inch thick form the walls of this attractive garage. The structure of the material is shown in the actual HIN, porous concrete slabs that are extremely light in weight yet strong enough to withstand a crushing pressure of 600 pounds to the square inch have been developed recently by a New Jersey manufacturer. Reinforced by wire netting, these con- crete boards, only an inch thick, can be nailed to studding much as lumber would be. Because of their peculiar air-cell structure, they are said to be exceptionally effective heat and sound insulators; while their resistance to heat, steam, or water, it is claimed, make them comparatively fire- proof. Mixed with Wax-like Pellets In manufacturing the slabs, cement and sand are mixed with a specified quantity of small pellets of a secret chemical composi- tion resembling paraffin wax. After water is added, the cement, sand, and pellets are mixed thoroughly, then poured into a steel form over wire netting reinforcement. As soon as the cement has set, the slabs are removed from the forms, placed on steel cars and hauled to a steam tank where, under the action of exhaust steam, they are heated rapidly. This heat melts the waxlike pellets, which drip out of the slabs into receptacles beneath the steam tank. size cross section at the left After about 24 hours of steam treatment that removes all traces of the chemical, the slabs are in a porous state. At this point they are cooled and placed in asteam curing room, where they are kept heated and moistened for two or three days until they possess the strength necessary for building operations. When used in connection with stucco fin- ish, the siding slabs are nailed to wooden studs with the wire mesh reinforcement out- ward. This makes a good base for the stucco. .Carried in cars to a steam tank, in background, the unfinished slabs are subjected to heat that melts the waxlike pellets, producing pores Water Pressure i in Tube Measures Depth of Soundings iAP ARATUS nS WEIGHT 2 APPA RATHS TO ROTTOM WOODEN GAGE GLASS | TUBE The brass pipe sounding apparatus, with weight attached to sink it Depth is determined by measuring rise of water in glass tube N INGENIOUS sounding _instru- A ment now in general use consists of a brass pipe inclosing an air-filled glass tube and a lead weight that carries the instrument to the bottom of the body of water where soundings are to be made. Depths are determined by noting the ex- tent to which water pressure compresses the air in the glass tube. The tube is open at the lower end, while the inside surface is covered with a water soluble dye. The in- strument is suspended from a thin wire. The water pressure at any depth is pro- portional to that depth; hence, as the in- strument tube sinks, the water entering the brass pipe rises higher and higher in the tube, dissolving the dye as it rises. When the instrument is raised, the depth of the sounding is determined by measuring, on a scale graduated in fathoms, the extent of the tube that is free from dye. March tra\ of

Page 13

nthly 5 ling fin- den ut- CC. March, 1923 The Story of Man and His World Beginning the Most Fascinating Serial of Science Ever Published Especially Written By Dr. E. E. Free for Popular Science Monthly Prepared with the co-operation of some of the world’s leading scientists

E. E. Free, Ph.D., scientist, engineer, traveler and writer of popular science

R. E. E. FREE, America’s best writer of popular science, ins herewith a wonderful series of articles on the secrets of life and mysteries of evolution. He tells the story of how the Life Force first took shape in the sea, a billion years ago; of how it ew into countless strange new forms; of how worms, ial reptiles, and apelike creatures each in turn inherited the flame of life and passed it on to still higher animals; of how finally Man himself emerged. And Doctor Free tells not only the Story of Life, but the Story of Science, by which we have learned Life's secrets. He tells how men have read Nature's picture- writing in the rocks, explored the heavens, probed the

First Article: The Dawn of Life E KNOW today that the earth is very old, older by millions of years than the scientists of twenty years ago would have believed possible. We now know that the great drama of life on earth, the drama in which you and I are playing our little parts, has been going on for more than a billion years. Think what this means. A period so in- comprehensibly long that a man’s whole lifetime is but a few seconds in comparison! Yet step by step back into this tremen- dous abyss of time we are now able to trace the evolution of man, the story of how every living thing in the world developed out of tiny life germs first born in the sea some thousand million years ago. Suppose you could have been present then—what would you have seen? In pools along the margin of the sea you might have discovered a speck or two of transparent jelly; here and there on the surface a little scum of slime. You would not have recognized them for living things alone. Behind the seashore rose smoke-crowned volcanoes. Against the barren cliffs surged storm waves of the primeval sea. Earth- quakes rocked the land. Lightnings flashed; thunders rumbled; down over the rocks there poured the floods of rain. And in the midst of all these natural wonders the greatest of them all would have gone unnoticed. ‘For the greatest of them, the most significant, the most important in earth history, were undoubtedly just those small slimy specks washing about in the seashore pools. These slime specks, or something very like them, became the parents of every living thing on earth. They were the first ancestors of man. Where these first living particles came secrets of invisible atoms, discovered queer animals in far corners of the globe, and finally pieced all these clues together into one majestic drama of the ages. Behind this drama some may see moving a Divine Plan of things; others simply the thrilling work of blind chance; but none can fail to be inspired to awe by the natural wonders so vividly presented in Doctor Free’s straightforward narrative of fact. Thanks to the co-operation of many eminent scien- tists whose help Doctor Free has had in preparing each article, the most amazing recent discoveries of science are now put within reach of the average busy man for the first time.—Tue Epitor.

in Pictures

What Your Body 1 Is Made Of The Story Told

2 Cu, FT.

RE OXYGEN, is 60 CU, FT. 1 NITROGEN, {! CUFT. 4 S HYDROGEN : The human _ body grows from a single egg cell, such as that IODINE shown ‘highly mag- EQUIVALENT nified at left. . Less 10 Vio OF ONE — a hundredth of DROP an inc ameter, it can produce an TINCT.OF1ODINE adult man com of sponte of sep- arate tissues D ABOUT containing all the apy a a — chemical elements NE PHUR,AND eM

illustrated at right

The Same Story in Percentages This picture illus- trates what you would pine oe if you ana- ‘contente” } an average man. These chemical cone stituents of the nor- mal human body have a market value of about 98 cents! The column below shows the percent- ages by weight of the elements mak- ing up the various tissues, while on the opposite side of the picture are shown the normal quanti- ties of each sub- stance. Note that the body is mostly composed of water 66% WATER

~~ 3.1 M.NITROGEN —~<— 2:F% HYDROGEN ~<— 15.8 % CARBON

aa ~~ 2.5 Yo CALCIUM Pal ~<— 2% PHOSPHORUS ii ] ~— 6.7% OXYGEN Besides the above elements the ~ y soe minute Cg of salt, sugar, pepe oe on. sulphur, iodine, m: and fusrine, totaling 6 a ee over four tenths of one per cent.

en!

mein

Page 14

Popular Science Monthly | yarch, 1 SULPHUR BOTTOM WHALE (LIVING) 87 FEET LONG ABOUT 90 TONS . a . PREHISTORIC BRACHIOSAURUS -87 FEET LONG, WEIGHT ABOUT 60 TONS. MOST MON- STROUS CREATURE KNOWN EXCEPT THE WHALE 2\ 4 2 lve MLL LLL ccc LL. ‘ jethbdlda This The Smallest Living Things “— 1—Imagine a man 1980 feet high—2 4 times the height of the Woolworth feermccomiecencinemnen PORTED eg a nig ——— ged pe niar: n exac e ota ia ° . . } ae pan ony hen ents of dhe from, we do not know. Distinguished consists really of a great assemblage of tiny that lif Cor ba alas ao dee _ scientists have believed it possible that the separate particles which scientists call micros¢ actual size shown below. The flagel- | germ of life first came to earth from another “cells.” There may be as many as a billion reasons dl oot os gag oo 7 planet; hidden, perhaps, in the crevices of of these cells in a cubic inch of flesh. Each from 81 form of life consisting of many cells ' ~ a meteorite or merely as living dust floating | human body asa whole contains thousands wired f a na _—star 6 HUM an “|, THE GERM OF _ eae gelling cannot positively say _ of billions of them. = ae RED BLOOD =3K: TYPHOID Z tag : . ‘ ‘ ‘ i CORPUSCLE oK salem ____, But it is more probable, I think, that Cell Units Perform Varied Duties —_ ae mia / living matter originated right here on cell in _ earth; that in the course of ages, combina- These cells are the units of life. There ‘ tions of chemicals took place spontaneously are many kinds of them in your body, each Ind y in the primeval sea; that as time went on, kind with a different duty. Inside your : * these combinations became more and more _ enlarged self you would see some cells busy still _ complex; that finally, without any very making juices to digest food. Others would alway: _ sudden change or clear transition, they be lengthening and contracting again as can lis , were alive—they were breathing, growing the muscles worked. Still others would be some _ particles of living matter. building bone where the skeleton was grow- few dr ‘ ing. Most wonderful of all, you would see om, AT RIGHT, Secrets of Life s Origin in Us some cells set apart for nerve duty. Grow- gathe A SMALL ing out of each one of these, you would cover ROTIFER, But how, you ask, can we know what notice a long threadlike tail. These tails living THE SMALLES1 the original living matter was like? Strictly are gathered into bundles to make up your of vie aa" speaking, we do not really know at all. But nerves. Even your highest organ—the little L _ We can make a pretty safe guess at it, a brain—is made up of cells, most of them plant ABOVE _ guess based on first class scientific reasons. _ tailed like the nerve cells, their tails con- of th | A-FLAGELLATE y One of these reasons you can find inside necting with innumerable other cells in the mals. PROBABLY , yourself. If you could somehow enlarge nerves or other parts of the brain and so worle RATHER LIKE __ yourself until you were some 5000 feet tall making up the intricate communication ng; THE ORIGINAL —about ten times as high as the Washing- system with which you think and govern inter LIVING ORGANISM ton Monument—you would be able to see your body’s actions. shap that your bones and muscles and other But beside the fact that human beings yet | re a tissues are not simple materials like glass and all other creatures are composed of this or wax, but that each one of these tissues cells, we have other reasons for believing Al Photo at left by Amer. Mus. of Natuxal History the ' Wie VILE + ae ie - 3—In the human blood we find 4—Here is one of the “‘single ' tiny cells that celled’’ creatures’ that : live independ- make up the ‘plankton’’ { ently. They are of the sea. Millions like it i the white cor- float in every cubic inch of F seers Mlb puscles, one of surface sea water. The : ne ; 2—Scientists read the story of life by which, enlarged earliest living thing was 5—Life first took form as a single studying fossils, which are shapes of more than 2000 probably a single celled cell. Later, groups of single cells aucient animals preserved in the times, is shown “plant animal,”’ even took to living together. The rocks. The photo above shows a above in the act much simpler than this. strange microscopic creature fossil ‘‘trilobite’’—half crab and half of ‘eating’ a The ‘‘plankton’’ feed by above, called ‘*Volvox,’’ consists of insect—just as he was buried in the disease germ by absorbing sunlight and such a colony of cells, most of ocean mud half a billion years ago flowing around it food chemicals them alike

Page 15

athly WMO

call ion ach nds

March, 1928 29

The Largest Flying Creature that Ever Lived Top pictures courtesy Amet. Mus. of Natural Historv

once lived where the state of Kansas is now.

This huge flying dragon, Pteranodon, measuring more than 26 feet from wing tip to wing tip, His wings consisted of membranes between his body and an overgrown little finger, some nine feet long. Note three other fingers like claws on his wings. He was a member of the family called Pterodactyls

11—Still living in East Indian forests,

that life itself began as a single cell—a microscopic drop of jelly. One of these reasons is that all living things today grow from such a single cell. And not only does every living thing—plant, fish, insect, man —start from a single fertilized egg cell, but . it grows to its final complex structure simply by division and subdivision of this cell into intricate cell colonies. Independent Cells Can Live Alone Still another reason is that cells do not always live in such colonies. Certain kinds can live alone, each cell for itself. Examine, some day, under a powerful microscope, a few drops of water from a pond, or from the sea, or from one of the little pools that gather in roadside ditches. You will dis- cover a new world, a world crowded with living creatures. Scattered over the field of view of your microscope are clumps of little greenish globes that really are minute plants; now and then you will catch sight of the darting, wriggly forms of tiny ani- mals. Along the bottom of your water-drop world you may see another animal creep- ing; a sluggish one, without any visible internal organs, continually changing in shape, looking merely like a speck of slime, yet unquestionably alive. Scientists call this creature the amceba. All these myriads of creatures that fill the water-drop world are so small that the unaided eye of man would never have sus- pected their existence. And most of them are single living cells, a good deal like the cells of your body, except that each one of them is independent and lives by itself. There are even some one-celled creatures like this that live inside your body as neces- sary parts of it, but without being attached to other cells and, so far as we can deter- mine, independent, just as though they were separate living creatures that merely condescended to make our body their home and do enough work to earn their keep. These free-living cells inside us are the white corpuscles of the blood. Under the microscope they are merely little specks of translucent grayish jelly. They look for all the world like the creeping jelly-drop ameceba that you saw under your microscope in the ditch water. These white corpuscles float around in the blood, visiting all parts of the body together with the ordinary red corpuscles that give the blood its color. So long as we are well, they do not seem to have very much to do. How White Corpuscles Attack Germs But suppose disease germs invade the body somewhere. The white corpuscles immediately mobilize like a well-trained army at the point of the germs’ attack. Wherever they find one of the invading germs, they dispose of it by the simple ex- this lemur, the Tarsius, is close to the line of descent of man. Some fifty million years ago, lemurs lived in

many parts of the world, including North America. From them devel- oped monkeys, apes, and man

y beet *. <%, & rF By A px

Courtesy Amer. Mus. of Naturai History 10—The ancient giant reptiles were among the most spectacular creatures developed in the evolution of life. This curious lizard from New Zealand— —the tuatera resembles some of them

Be Res 6 ond 7—Photograph ofa fresh-water hydra, taken from the only motion picture ever made of this curious animal. The hydra, found in ponds almost every- where, is about one six- teenth of an inch long

$ : i ec wind RN ai as Se

7—Representing one of the simpler forms of the great group of many-celled micro- scopic animals that probably develo from cell colonies like olvox (see opposite page), the hydra has eight waving arms about his head. These arms seize food and cram it into the mouth, at the end of the body between the arms. Thus the cells that were all alike in earlier . “‘cell colonies’’ have now be- come specialized, and the creature has a body with various rts carrying on different jobs. The little bulge | on the abfe of the body is a ‘“‘bud,’ beginning of a new hy Ya This bulge will grow Snaee, develop a set of arms of its own, and will finally drift off by itself, a complete new animal. The hydra also reproduces oesually Photo courtes Carpenter-Goldman L Dicehedion

OPO OOM LOM CMM OMOEA LESS Se STOEL GA 9— Venus’ fly-trap—one of the strang- est of plants—has on each leaf three little hairs: When an insect touches

8—The sea uirt, beginnin life asa backboned animal, ~ generates to plantlike growth one of them, the halves of the leaf close, trapping the tuckless insect, which the leaf then digests

Page 16

30 pedient of eating it up. The way in which they eat it is very interesting. Having en- countered a germ, the corpusele proceeds to flow around it. Little knoblike projec- tions are pushed out of the corpuscle’s body on each side of the germ; these meet on the farther side and join, so that the luckless germ is actually engulfed inside the body of the corpuscle. Once in there, it is soon digested and troubles our body no more. Now one of the most curious and inter- esting facts in all biology is that this way of taking up food by flowing around it is exactly the way in which the. ditch-water jelly-drop—the amceba—takes up its food. This tiny free-living creature not only looks just like our body guest, the white cor- puscle, but also eats like it. And both illus- trate the fact that living matter is made up of individual cells and that some kinds of these cells can live alone. All Cells Made of Same Material And not only are all living creatures alike in being composed of cells, but al! these cells have inside them very much the same kind of material, a jelly-like substance that scientists call protoplasm. It has much the appearance of uncooked white of egg, though usually a little stiffer. Living creatures are of the most diverse forms—a starfish, a snake, a man, a tree. One would not expect them to be composed of the same material. Yet they are. They are all made up of cells and all the cells con- tain protoplasm. So far as we ean deter- mine, it is very much the same kind of protoplasm. How is this to be explained? Quite simply, if we accept, as most scientists do, the idea that all these diverse creatures are descended from a single ancestor, an an- cestor who consisted of a drop of proto- plasm living as a single independent cell in the primeval sea. But, although the protoplasm of all cells appears to be much alike, you must not believe that it is exactly alike or that modern protoplasm is exactly the same thing as the original living matier. In the millions of years since life began on earth, protoplasm has changed just as everything else has. It has become more complicated. Different varieties of it have been developed to suit the kinds of work carried out by different kinds of cells. Protoplasm Eats, Breathes, and Moves The things that protoplasm does are enough to prove that it is complicated. The living cells composed of it are able to eat, to reproduce their kind, often to move about. All of them that have been investi- gated have another characteristic: They breathe. Human breathing is typical. You take air into your lungs. Oxygen from the air combines chemically with a certain sub- stance in the red corpuscles of the blood. These corpuscles laden with oxygen are then carried to all parts of the body. They give up their oxygen to the body cells. These cells take up the oxygen and use it, giving back to the blood a chemical compound of oxygen with carbon, the compound called carbon dioxide. This is what breathing always is: Proto- plasm takes up and uses oxygen. It gives off carbon dioxide. Every animal breathes in this same way. Every plant does like- wise. The one-celled animals, which have no lungs, breathe by taking up oxygen directly through their surface, just as the individual cells inside our body take it up from the blood. (Continued on page 118) Fi Ni 4 PRIMITIVE HOOFED ] ANIMAL ~'SNAKES ROACHES { COMMON EARTHWORM “FIRST | ae INSECT | @ RTE: Popular Science Monthly B EGG-LAYING MAMMAL AMPHIBIOUS | J LIZARDS £ My PRIMITIVE | WORM

Page 17

March, 1923 bape atresia A ng a Baciey st nay t na ppllihint ame mse meen eat phere set Sip Te A Picture Story of Evolution HIS remarkable chart of the family tree of man gives you quickly a vivid idea of how life, Originating as a single cell in the sea, spread over the earth, developing into the myriads of queer forms of plants and animals and ending in man. Start with the white circle at the bottom of the opposite page and follow upward from the primitive the four great branches into which this tree of life is divided. IRST is the branch of plants. Second is that of the molluscs, culminating in the octopus and giant squid, the most intelligent creatures living in the seas. Third is the great branch of the insects whose highest creatures, the ants and bees, represent the perfection of those social instincts that make each individual a slave to the rules of the hive. FPINALLY there is the great branch of the verte- brates or backboned animals. At their highest point we have MAN. This is the branch of individual intelligence, of creatures who think for themselves in- stead of obeying blind instincts, asdothe ants and the s. An early human type—the cave man—is shown. You will find innumerable fascinating points in the chart; note, for instance, the close relationship of bear and dog; the tiny ancestor of the modern horse; how the seal is related to catlike animals, etc. aps a Sena ERE ES EA RE A OT OYSTER

Page 18

32 Popular Science Monthly Historic “Leviathan” Becomes Queen of the Seas F i - @g~ Pd /. hy. ne / r3 ; sda Se a ees From troopship to floating palace—the mighty ‘“‘Leviathan,”’ second largest vessel in the world, as she appears at Newport News, Va., in the process of transformation, at a cost of $8,000,000, into the most magnificent of al HE most stupendous task of its sort ever attempted in the history of shipbuilding is now under way at Newport News, Va., where the historic “Leviathan,” next to the largest vessel in the world, is being converted from a bat- tered troopship into the finest passenger liner afloat. When the monster ship that carried 104,500 United States officers and men in 10 trips to France during the war, sets out on her maiden voyage as a passenger carrier under the American flag early in the present year, she will represent the last word in sea- going luxury. Five years ago the ‘Leviathan,’ formerly the German “Vaterland,”’ was carrying U &U. WINTER GARDEN MAIN TURBINES He, OR This cross section diagram of the re-designed ‘‘Leviathan,”’ shows arrangement of luxurious passenger accommodations. On one trip during the war, this mammoth vessel carried 12,000 troops—a throng visualized in the larger inset, showing a more than 10,000 American soldiers on each trip to France (in one trip she carried 12,000). Two years ago she lay rotting at her pier at Hoboken, N. J., while shipping men called her a “white elephant” on Uncle Sam’s hands. They said the day of monster liners had passed, and that the “Leviathan” might as well be towed into the Atlantic and sunk. Now more than $8,000,000 and the daily labor of 2500 men are being spent on her to prove that America’s merchant marine, after all, can support a liner outclassing the world’s finest. Eleven electric elevators are being in- stalled. Oil will replace coal~ under her boilers. To protect the ship from any pos- sible increase of fire danger, marvelous new automatic safety appliances have been adopted to flood the boiler rooms with a smothering foam in an emer- gency. . Contrary to century-old conditions, a “‘andlubber” maritime architect funnels. section of the Harvard stadium. her tremendous proportions—Columbus’ flagship, the ‘‘Santa Maria,’’ placed on end, would not reach top of ‘ passenger liners has been employed to re-design the interior. Her elaborate lighting fixtures will glow with 15,000 electric lamps. The entire ship is equipped with an intricate system of telephone communication, 600 instruments being connected on a central board. To prepare food for the 5000 passengers and crew, seven complete galleys and four bakeries are being equipped. More than half a million dollars is being spent on the steward’s department alone. For the din- ing rooms there will be 150,000 pieces of china and glassware. On every round trip the vessel will need three tons of tea and coffee, and 186,000 pounds of meat. Since the only plans of the “Leviathan” in existence were in the hands of the Ger- man builders and were obtainable only at a prohibitive price, the American designers were compelled to adopt unique detective methods to remodel the ship. It was neces- sary to follow out all the wiring and plumb- ing lines and to ascertain accurately the sizes of hidden structural members. The smaller inset illustrates viathan’s’’ White portion represents section shown below March, R — ~n ete Ae Teo se" w

Page 19

wthly S ——.

March, 1923 33

Record Glider Revives Langley’s Tandem Wings

rior. slow ship of ents yers four ~~ han © Flight the The world’s record flight of M. Maneyrol’s tandem monoplane glider on the Sussex downs, England. Note the amazing lin- altitude gained by Maneyrol by taking advantage of air currents (at right). Inset shows the glider nosing into the wind ; of trip By Lorry Jacobs formance. “Every now and then the glider The wings, characterized by a pro- and hovered with its nose to the wind. Some- nounced backsweep—the front wing being REDICTIONS of two far-seeing times the wind’s velocity dropped and the placed at a larger angle of incidence than an”? American aeronauts have been re- machine began to glide downward and for- the rear—consists of light ribs, placed some- ‘or. markably borne out by the recent ward. The pilot then resumed his tacking. what far apart, carried on tubular spars of ita record-breaking motorless flight of M. At other times the wind blew the glider duralumin braced by duralumin N struts. ers Maneyrol, French airman, in a Peyret backward slightly, but by ‘diving,’ Man- The controls are constructed with a ive tandem monoplane glider in which he eyrol got away from the hill ‘where he differential formed by three bevel gears e3- stayed in the air for three hours, 21 min- took off.’”’ nb- utes, and seven seconds, winning the London While the tandem monoplane de- Structural de- the Daily Mail’s prize contest on the Sussex sign of Langley has been little used tails of the Pey- WING FLAPS downs, England. in powered flight because the rear ret Feces ze In the first place, the design of the ma- plane is far less efficient than the prea ° te g== tame fe chine that made this record follows the front one, Peyret realized that the control f i essential tandem lines of the famous tandem arrangement, when applied PILOTS COCKPIT t steam driven ‘“‘aerodrome” used by Prof. to a glider, facilitates control. H Samuel Pierpont Langley for the : i! i second successful flight in history, © 7s Sa eee ccna se rsa <6 years ago. an peo ee Secondly, the successful meth- RUDDER} ods used by Maneyrol in piloting i his glider fulfilled the promise h made in the November POPULAR ‘ssae . SCIENCE MONTHLY by Augustus Post, secretary of the Aero Club of America, when he said: “During the period of increas- nalts ing wind velocity, a pilot of the future will turn his plane head on so that when the “stick,” or con- . to the wind and steadily gain trol column, is pushed forward, . height. As the wind decreases in the flaps of the front wings are ' _ velocity, he will turn at right raised and those of the rear wings angles. And at the beginning of lowered. When the stick is push- a period of minimum wind speed, ed to the left, the starboard flaps he will turn tail to the wind.” It of both rear and front wings are was this scheme of flying, com- depressed, those on the port side bined with an advantageous and being elevated. Any combination continuous updraft along the of forward and sidewise move- take-off hill, that won for Man- ment of the control stick is pos- Tn flight bled that of Ot | is obtained “The flight resemble at o 3 . : Directional control is obtaine a bird,” says an authoritative chet connie smuann aon gies ee ee by means of a rudder manipu- report, describing Maneyrol’s per- seven seconds, establishing a new world’s record lated from a footboard.

Page 20

Popular Science M onthly Storage Hopper Speeds Up Loader * MEANS of a storage hopper that can Universal swivel be adjusted to hold a specified quantity spout from storage hopper Compact Oxygen Apparatus for Mountain Climbers DVENTUROUS scientists who re- cently attempted to scale Mount Everest in the Himalayas might have been successful if they had been equipped with a newly invented portable oxygen apparatus, designed especially for mountain climbers and aviators, which supplies just the right amount of oxygen at any elevation. The amount of oxygen required by a mountain climber varies from 61 cubic inches a minute at 13,000 feet to 183 cubic inches a minute at 26,000 feet. Thus at any given elevation, as indicated by a barom- eter, the valve is set at a corresponding figure, allowing the correct amount of oxygen to enter the breathing bag. A small flap valve prevents exhaled air from enter- ing the bag. Inability to obtain sufficient oxygen re- sulted in the failure of the Mount Everest expedition to climb beyond the altitude of 27,364 feet. At the 23,000-foot level, one of the climbers became ill and oxygen was used more extensively; but because of the weight of the apparatus, progress was slow. of material on a new tractor-loader, manu- factured at Columbus, Ohio, batches of spots material on the truck material in de- quickly sired amounts are elevated to the hopper and held in readi- ness for the next receiving truck. The fact that the eleva- tor is kept at work continu- ously greatly increases the capacity of the loader. A universal swivel spout adds to hop- tm - es son ate tee ~~ a per’s efficiency. Elevated material is stored in hopper until truck arrives -Calendar-Desk Pad Fed from Paper Roll Din tereioerd with a roll of paper such as that used with an adding or calculating machine, a handy desk pad recently placed on the market enables the user to record data, from day to day, on a continuous sheet of paper, much as stock quotations are recorded on ticker tapes. The base of the calendar has a bronze finish. When the exposed surface of the paper has been used up, the new surface is ad- vanced by pulling on the end of the roll. The paper can then be torn off or left as a continuous record. A permanent calendar attached in front of the roll can be used indefinitely. . How: light from. the curved lamp passes through teeth under examination Dental Lamp Casts Light through Teeth ao ee of dental diagnosis have . been perfection of a mouth lamp that passes light through the teeth. The fact that the light from the usual mouth lamps is not sufficiently in- tensive for this purpose has long been a handi- “cap to dentists. In the new lamp the source of light is a filament, and the rays are projected through a lens that produces Light rays from filament, passing through a lens, are intensified in part overcome by the recent intense illumination. Thelampiscurved, sothat when placed in the _ patient’s mouth, it projects the light at right angles directly through the teeth. Since the lamp tube contains a vacuum, the out- side remains cool. Falling Ton Weight Tests Strength of Axles CSpeeeag a single defective locomotive axle may cause a disastrous train wreck, manufacturers submit a certain percentage of each batch of axles turned out to tre- mendous shock tests. In the final test each axle is supported near the ends while a weight of 2240 pounds is dropped on it twice, the axle being turned through an angle of 90 degrees between the two shocks. These two blows are considered sufficient to reveal any flaws in the material that may have escaped notice in previous examinations. The height from which the weight is dropped varies with the diameter of the axle. Thus, for a 6 7/16-inch axle, the weight would be lifted to a height of 414% feet and then dropped. Saree amare IO i > Locomotive axles are tested by a weight | dropping on them mo’ me’ san cy¢ aln des wa ing the st¢ so) coinin: Potosi wheels clock, the st pins w upon power

Page 21

vel om per ‘ial ick ts sand. making quick stops, is in the form SWITCH SPRING The problem, as analyzed by this of a leaf spring, which holds the cut- , cyclist, whose work takes him into out switch in circuit, making it nec- etn age ag tn eae axle almost inaccessible mountain and essary to break the circuit to ope- serted under spring, reck, desert country, consisted of finding a rate the motor. closing the cut-out and ' tage way to give the machine a “boost” In order to keep the cut-out stopping the motor ; tre- while working single handed—operat- switch circuit broken wh le the cy- ing the motor while pushing and lifting _clist works behind the machine, asmall block holds the cord attached to the cut-out \ rted the machine—and also a means of of fiber was inserted under the spring. To switch, and the machine goes ahead as inds stopping the motor once the machine this a length of stout cord was attached. long as he follows it. To stop it, he ‘ med was out of the hole. Here’s the way he Now, when his sidecar is stalled, the just stands still; for the cord held in a _ the solved it: motorcyclist simply ties the handlebars. his teeth will instantly pull out the i & ered To keep the stalled machine straight | He then starts the motor, puts the machine _ fiber block and close the short circuit 1a rial on its course, the motorcyclist simply in low gear, and engages the clutch, then _ of the ignition system. if ious tied the handlebars. Then, to prevent jumps behind the machine to lift and The plan might be applied to an the machine’s running away and _ push it out of the mire. In his teeth he automobile in a similar way | 1 t is | the ‘ the ‘. y '% | Mules Drive Wooden Geared Money Presses | — yy ores minting machinery more machinery. Eight mules provide the power than 300 years old is still in use for and it is estimated 100 tons pressure can be coining medals in the government mint at applied to the dies. Potosi, Bolivia. Although the wooden gear This pin gear, as it is called, has become wheels resemble those in an old fashioned almost obsolete. It is still seen occasionally & clock, and it might be expected that either in clocks and in feeding devices on milling { 2 the short wooden pegs or the ladder-like machines. Wherever wood must be used, pins would be broken if the gear were called however, the pin gear is the perfect design, March, 1923 35 : Drives Motorcycle out of Mud and Stops It with His Teeth | Y THE clever use of stout twine and a cut-out switch, a Western motorcyclist has devised an ingenious method of extricating a stalled sidecar motorcycle outfit from heavy mud or Holding in his teeth a cord that controls the motor through an ingenious cut-out switch, the cyclist starts the motor, then boosts the machine out of the mire being damaged, he fitted an ingeni- ous motor cut-out switch to the right handlebar. This device, a modification of the usual cut-out switch used by motorcyclists for With handlebars tied, the machine goes straight ahead. fo stop it, the cyclist need only stand still, for the pull on the cord in his teeth shuts off the ignition FIBERBLOCK Leta == OLS, — = METAL CLAMP YELL a HARD RUBBER SWITCH BLOCK MOTORCYCLE HANDLEBAR ~g i RUBBER BAND AROUND CUT-OUT upon to transmit any large amount of power, excellent coins are struck with the since the strain is always applied at right angles to the grain of the wood. “~~ Snow Skating Latest Sport A NEW winter sport has come to us in the form of snow skates, invented by Peter Barlow, of Minnesota, which can be used in gliding over snow only half an inch deep. The wooden runner has a broad steel shoe and is fastened to the skater’s shoe in the same way that ice skates are clamped. The turned up toe serves to pack down the loose snow and to prevent the skater from tripping as the skates sink in. The ancient money press in the government mint at Potosi, Bolivia, show- ing pin gears resembling works in an old clock. This press is 300 years old

Page 22

36 NEW method of equipping the home with storm windows, said to be more satisfactory than the pres- ent clumsy outside sash, has been de- vised by a concern in St. Paul, Minn., which utilizes the regular sash as a base for a second pane of glass. The inside edge of the window sash is cut to receive a metal strip, the side of which is pressed into a groove to into a frame that just fits the window and is held in position by keys provided at several points along the Double Glass for Storm Windows receive the pane. This strip is made upe edges. The purpose of all storm windows is to provide a dead air space _ be- tween two sheets of glass so that the amount of heat lost will be re- duced to a min- imum. While the old method Above: Second pane of glass fitted into metal strip inserted in inside edge of the sash At left: Releasing storm window with screwdriver of attaching ad- ditional windows during the inclement weather of the winter months has done this, yet there have been many oppor- tunities for improvements from points of view of economy and beauty. The new sash does not mar the beauty of a building and, because of this, it can be left in position at all times. The joints are so tight that no dust can penetrate to necessitate clean- ing the windows between the panes. To remove the sash, it is necessary only to turn a screw in the key seat with a screwdriver. This releases the frame and the sash can be withdrawn. While the sash is made in standard sizes and can be substituted for the ordinary sash in a standard window frame, the molding is especially de- signed for the storm glass frame. Cable Fence along Highway Protects Motorists bd ALL highways were lined with a cable fence such as is used on the Lackawanna Trail in Pennsylvania, motor accidents caused by swerving off the road might be minimized and the number of deaths cor- respondingly decreased. Two three-quarter-inch cables are stretched between posts on those sections of the highway that run along the side of hills orembankments. Thus, should a car strike the fence with sufficient force to uproot two or three of the posts, the cable, which is con- tinuous, would still hold and would prevent the car from crashing down the declivity. S A special service to readers, the Editor will be glad to supply, wherever possible, the names and addresses of manufacturers of de- vices mentioned in this issue. Popular Science Monthly Portable Stackless Stove Keeps Workmen Warm FOR the use of workmen in smal] shops where there are no heating facilities, and in buildings under construction dur} the cold weather, a portable coke stove hay recently been placed on the market by 4 manufacturer in Trenton, N. J. The stove is made of cast iron and has a single opening at the side through which the coke is fed. An opening at the bottom provides the draft necessary for combustion. No stack is pro- vided, since the stove is used in places where it is usually possible to discharge the flue gases into the atmosphere. Coke is fed through square opening Sixteen Million Books eom 10 to 20 million books have been published since the invention of mov- able type in 1454, some authorities placing the number more accurately at about six- teen and one half millions. These have been issued in the following order: fifteenth cen- tury, 40,000 volumes; sixteenth century, 570,000 volumes; seventeenth century, 1% million volumes; eighteenth century, two million volumes; nineteenth century, 8% million volumes, and 4 million since the beginning of the present century. Two-Deck Bus Built Close to Ground gr sesegrsbangd to increase safety and com- fort for passengers, a double-decked city type motor bus of unusual strength and stability is being built by: California manu- facturers for interurban transportation. To insure stability, the frame of the bus is set only 14 inches above the ground, while the gage of the car—the distance between wheel treads—is 70 inches. The frame of the chassis is of six-inch rolled structural steel channel, riveted at all joints. The two decks provide seats for 46 per- sons—24 in the interior and 22 on the upper deck. Cross seats in the interior are reached through side doors equipped with drop win- dows, while seats on the upper deck are reached by a flight of steps leading from the front end of the bus. . Drop windows of plate glass running in felt grooves disappear into the doors, which extend to the runningboard. Driven by a four-cylinder gasoline en- gine of 62 horsepower, the car will develop a maximum speed of 49 miles an hour. Be- cause of the exceptionally low center of gravity, the bus holds the road well at curves and is practically free from danger of overturning. Baht. ' The double-decked safety passenger bus, showing low-hung body, stair- way entrance to upper deck, and side-door entrances to interior = Lamy NE tak both a the roo light fr This with a: top of translu reflect¢ dur clu olo

Page 23

moy- it six- y, 1% 7, two a 8Y e the ) win- k are m the ng in loors, e en- velop er of ll at anger March, 1923 Special Home Saves Time for Fire Chief Below the fire chief’s rooms is his garage HE San Francisco fire department is making new efficiency _rec- ords by having a specially con- structed _resi- dence for the fire chief, mak- ing it possible for him to at- tend a fire as quickly as the engines. When there is a fire, an alarm wakens fire chief and drivers, and automatically opens garage doors. Lamp Attachment Provides Indirect Lighting NEW attachment for electric floor and table lamps makes it possible to obtain both a desirable diffused light throughout the room and the reflection of a brilliant light from the ceiling. This indirect lighting adapter is provided with a screw that will fit into a socket in the top of the lamp, and is constructed of a translucent glass bowl surmounted by a reflector. When the adapter light is used, Translucent bowl sheds dif- Reflector form- ing upper part of this lamp fused light gives indirect throughout lighting the room the lower bowl sends out a diffused light and the reflector sends light rays toward the ceiling. With this new invention, any home can have indirect lighting, considered the best method of illumination from a. hygienic point of view. Origin of Righthandedness ‘Tt righthandedness developed when man began to use metal instruments during the so-called bronze age is the con- clusion of Sarafin, eminent French arche- ologist, as the result of a study of imple- ments used at various periods. Bristles at Both Ends of Novel Toothbrush NEWLY invented toothbrush equipped with bristles at both ends, affords a means of cleaning teeth better than the ordinary brush. The smaller brush is held in the handle by friction and can be removed instantly when it is desired to use the big brush. Thus it is kept from contact with the hand. The small brush efficiently cleans the inner sides of the teeth and the surfaces between them. 37 Five Photos Are Taken on Same Plate J. APPARATUS that photographs an object from five sides simultaneously, and on the same plate has been designed by the photographer of Johns Hopkins Hos- pital, Baltimore, Md. The object to be photographed is placed on the floor and the camera positioned so as to obtain a direct view. Mirrors are placed By means of mirrors, top and sides of the object are photographed simul- taneously on the four adjoining sides of the object so that a direct view of each of the sides is recorded on the plate. The finished picture consists of a central main view and four auxiliary side views. In the old way, five separate exposures were required. Pullman Car Walls Built in One Piece Sections are put to- gether on the ground and hoisted into posi- tion by cranes and fastened there by gangs of workmen, who place the stand- ards into their proper location. Y BUILDING the longitudinal sec- tions of Pullman cars in one piece, the man- ufacturers have added greatly to passengers’ safety. Shop riveting is much more satis- factory than field riv- eting, it is found, with the result that the sections have a much greater power to re- sist impact.

Page 24

si Popular Science Monthly “Thermos Bottle” Holds Molten Iron in Ford Plant O ELIMINATE double heating of metal used in auto castings, the River Rouge, Mich., r foundry of the Ford Motor Company em- x Marel ploys a container, operating on the principle of a thermos bottle, in which the molten iron, coming from the furnaces, is maintained at white hot furnace temperature until the casting room is ready for it. The usual method has been to cast the molten iron into pigs made up of the proper chemical composition. These pigs are melted a second time whenever it is desired to make castings—a duplica- tion that results in considerable loss of time and labor. The new container, with capacity of 25 tons, consists of one cyl ndrical shell within another, the inner one being lined with firebrick. At each end is an opening, one to receive the molten metal, the other to act as a spout in pouring the castings. The low conductivity of firebrick makes it pos- sible to keep the iron at FROM FURNACES « ’ white heat for five hours, during which time the con- tents can be used up for cast- ings. The proper chemical com- A position of the metal is ob- tained by tests of the iron in the container. Since the ore is not uniform, it is nec- essary to “doctor” it after OLDING molten iron at white heat until ready to be etl smelting. Thus if it is found transferred to the foundry, the “thermos bottle’ con- ent that a batch contains too tainer shown above in Ford’s River Rouge plant, represents a of | little carbon, the metal in striking advance over the usual method (at left) in which the cau the container is mixed with molten iron is cast into pigs. These pigs are commonly al- for a precise amount of cupola lowed to rust in the open, then they are remelted for casting. | . By the new method, molten metal enters one end of the wo iron of greater carbon _—" container, and when wanted is poured from the other end of : tent. The result is the de- into monorail buckets that carry it to the foundry pe sired chemical composition. m« e e of Sander for Motor Bus Stops Skidding 4 Ma of the accidents caused by the skidding of motor cars may be pre- vented by the use of a sanding device in- vented by August Schon, of New York City, and successfully tested recently on New York municipal passenger buses. This anti-skid apparatus consists of a circular drum, attached to the under side of the chassis in front of each rear wheel. The drum holds eight hermetically sealed con- tainers in each of which are three pounds of sand. The tripping of a lever near the driver’s seat releases the sand. The sand, dropping Tests with this New York municipal motor bus, carrying 40 passengers and equipped with the sanding device shown at right, showed that the sand, poured in front of the rear wheels, stopped the car within a third of the usual distance after the brakes were applied Photo courtesy Motor to the ground in front of the rear wheels, gives them an immediate grip on the road surface. In fact, it is claimed that a bus carrying 40 passengers and equipped with the sand- ing apparatus can be stopped within three feet when traveling at a speed that would otherwise carry it nine feet with brakes set. The apparatus can be attached to touring cars without interfering with the entrance to the tonneau, for the nine-inch drum can be mounted in front of the rear mudguard, the sand flowing through a hole bored in the runningboard beneath the drum. \G a + TKED BLADE. Rotary Scissors for Tailors A NEW rotary cloth cutter, invented by John Holtzman, of Brooklyn, N. Y., has been designed to replace the shears as a cutting agent in large tailoring establishments, where it is said to turn out better work in shorter time. It-consists of a rotary cut- ter that presses, while rotat- ing,’ against a fixed blade. This cutter is rotated by "| means of a toothed gear * wheel, the lower part of which rolls along the surface upon which the cloth is laid: Thus by grasping the handle and inserting the fixed blade of the tool under the cloth at the point where the cut is to containers. Attached beneath the chassis in front of each rear wheel, the sander consists of a cylindrical drum holding eight sand A lever at the driver’s seat releases sand from one container at a time start, then pressing down on the handle and moving in the desired direction, the opera- tor can cut material in any pattern desired. The new tool, while based on much the same principle as ordinary shears, is said to produce a cleaner cut. —s

Page 25

onthly unt con- ats a - March, 1923 Let a wall support legs as illustrated Run around room on hands and knees From kneeling position lower your chest to floor Lie flat and raise each leg vertically Lie flat and raise both legs vertically Upside Down Exercises to Keep You Fit Medical Expert Recommends Reversals in Posture to Stir Circulation of Stagnant Blood, Energize Under-Fed Nerves and Tone Sagging Digestive Organs that Have Grown Lax through Ages of Walking Erect By Edwin F. Bowers, M.D. Author of ‘‘Teeth and Health,’’ etc. stand on your head a certain number of times every day, physicians now agree that you might guard against many annoying ills of later life, from which few of us suffered in childhood, perhaps just be- cause we did stand on our heads or per- formed other similar feats. The rather absurd looking, but really worthwhile exercises illustrated at the top of this page are urged upon us by health ex- perts, to remedy the slumping of our inter- nal organs caused by today’s unnatural modes of living. The chief health benefits of thus figuratively “standing on our heads’”’ are these: |: YOU could hang by your heels or ogi) A Blood-Stirring Gravity Couch UPPLEMENTING the exercises shown at the top of the page, this tiltable table or “sravitizer’’ has been devised by Dr. William West, osteopathic physician of New York City, to relieve ailments traceable to our fail- ure to exercise blood vessels and bodily organs by varying our postures. Lying outstretched, as shown above, the patient’s body is inclined head downward for a specified period. This movement the patient himself may control by means of a lever with adjustments pro- viding for 40 different degrees of inclinations It exercises blood vessels and stirs normal blood circulation through bodily tissues, thereby stimulating the natural processes of repair. It puts elastic “‘tone’ into the blood vessels of the brain, so that nutrition of the brain cells and elimination of waste become normal, and the maximum mental efficiency is achieved. It tends to draw back into proper posi- tion abdominal organs that have fallen from their normal place. Finally, it stirs to activity a vital, little known watery substance—the cerebro- spinal fluid—that should normally bathe the brain and circulate through the spine, but tends to become stagnant. To the fact that we walk about on two legs, instead of running about on all fours, may be traced the ills that these exercises ‘overcome. Indeed, when some apelike ancestor of ours, millions of years ago, first awkwardly elevated himself on his hind legs, thus first setting for mankind the fashion of walking erect, he sowed the seeds of a host of human ailments, although at the same time he made possible the development of our hands, brain, and speech—the sources of all civilization. The erect posture changed the center of gravity of our internal organs, causing the stomach and intestines to hang unnaturally from the backbone, by tissues that have a tendency to relax, and let them sag déwn- ward into the abdominal cavity. This relaxed condition, so doctors of all schools of medicine are now agreed, is responsible for, or contributory to, scores of the common ailments from which we suffer more or less all our lives. A Source of Many Ailments When we have “the blues,” or a bad temper, or suffer from headache, dizziness, insomnia, nervousness in its thousand and one forms, indigestion, flatulence and obsti- nate constipation; when we wear a worried, haggard look; when our skin is sensitive to the touch, and either abnormally dry or profusely covered with sweat; when general catarrhal symptoms manifest themselves and bodily resistance to disease is lowered, we may be suffering from nothing more or less serious than this fallen state of the heavy organs of digestion. If you will realize these facts, you may take more seriously than the average man EACH CL! does the various sets of exercises pre- scribed by physi- cians and physical culture experts—the phonograph record exercises now popu- - lar and the outdoor sports of golfing, swimming, and row- ing. In fact, so im- portant is the prob- lem that an osteo- pathic physician of New York, Dr. Wil- liam West, has re- cently invented a mechanical device called theyp“ gravi- tiser,” a gravity FOOT STRAP CK OF RATCHET ONE DEGREE couch which, he

Page 26

40 claims, relieves many ailments that may be traced either directly or indirectly to our failure to exercise blood vessels and organs of the body by varying our postures. Physicians detect a condition of fallen stomach and abdominal organs by a medi- cal examination in which the positions of the abdominal organs are outlined by tap- ping the body, or by administering food containing a bismuth compound. In the BRAIN CEREBELLUM ARROWS Popular Science Monthly dominal muscles, and one that any person can practice easily, is this: Lie flat on the floor and slowly raise your feet and legs until they form a right angle with your body; then slowly lower them, at first repeating the exercise only ten times, morning and night, gradually in- creasing the number to thirty, or even forty times. Here are other simple exercises that will INDICATE FLOW latter case, X-ray photographs show the URRY Gee OF CEREBRO- prove helpful: shadows of the metallic element in an ab- ss iaiaabciaaiaal dominal cavity. When we suffer a falling of the intestines, the liver, spleen, and kid- neys are usually also involved, complicating the situation by becoming sluggish. Thus it is that bowels lose their ‘‘tone,’’ slowing up the wormlike motion of the muscles of the intestinal walls that finally pass intes- tinal debris out of the system, permitting the accumulation of quantities of waste matter in the bowels. This in turn results in the absorption of poisons developed by decomposition of the accumulated matter. Causes of Falling Organs A general falling of the organs (called “visceroptosis”), involving the large nerve network, or nerve center, in the abdomen-— second in importance only to the brain itseli—may produce any one of a wide variety of diseases. Falling of the stomach and abdominal organs occurs among all civilized peoples. Among its causes are the wearing of cor- SPINAL CORD ——4 A Health Giving Fluid Walk around the room “‘on all fours.” At intervals assume the ‘‘knee-chest” position—that is, while in a kneeling posi- tion on a bed, turn your head to one side and lower your chest to the bed. Lie with knees flexed and massage your abdominal organs, always taking care to force the organs upward. Supplementing such exercises as these is the gravity couch, or tiltable-table, upon which the patient lies outstretched, and by means of a lever inclines his body, head downward. It is 2D00CC equipped with adjustments to provide for 40 different de- grees of inclinations that progressively increase the in- fluence of gravity on the body, one degree at a time. The device makes use of the principle that the blood in the human body, since it is inclosed in elastic and nerve-con- ; trolled tubes, is not P sets, girdles, and other clothing that distorts Hat ge lenel _ ——— , instantly influenced the body; improper breathing, sedentary ns ope ig e oreaiiy bathes by gravity when the t habits and lack of exercise, inadequate the brain and spinal cord. Unless position of the body t rest, high heeled shoes, overeating, Over- stimulated by exercises, this fluid is reversed, but re- : drinking, excessive use of tobacco or other _ stagnates, causing mental and phy- sponds only after the ‘ narcotics and stimulants, or plain worry. sical depression lapse of five seconds. ' In extreme cases of falling of the stomach and abdomen, the bowel, instead of slipping down like a solid structure, collapses upon itself as if it were a wet cloth thrown into tubular form, creating folds, creases, and wrinkles that frequently cause acute illness or chronic distress. Even the normal per- son may realize in a degree the effect of a falling abdomen or stomach. Let some one stand behind you, raise your abdomen and support it for a few moments. You will ex- perience a feeling of lightness and buoyancy vastly different from the dragging, heavy sen- sag into its usual, but un- natural position. In addition to the exercises of stooping, twisting, and turn- ing that have been recom- mended by physical culture ex- perts, an excellent method of strengthen- ' _* ing the ab- ' FRORE STOMACH One Result of Erect Posture Thus, because’ the walls of the blood vessels do not release their tension until five seconds after the pa- tient’s body is_ in- clined, the device may be used safely within that time, to exercise the blood vessels and bodily organs to the In health, your body should contain about 80 cubic centi- meters — about two tenths pint —of cerebro- spinal fluid. A sation that follows when the erious excess limit of their endur- ' lifting support is removed, and may cause ill- ance. ; the abdomen is permitted to ness In whatever por- tion of the body the blood flows, or can be made to flow, by gravity, the natural processes of repair are stimulated; for this flow restores circula- tion in tissues where blood circulation has been feeble and inactive. Nerve cells that may have been starved or poisoned are fed and stimulated. Blood vessels in remote canals of the bones are reopened. Indeed, every organ of the body is energized by the flow of blood through it. Meanwhile, the tilting of the body backward swings the stomach and abdominal organs back into their normal positions and tends to maintain them in these posi- tions by strengthenifig the support- ing tissues. It is claimed that the blood vessels of the brain are thus exercised, tending to relieve depres- sion, and restoring mental efficiency. Finally, the watery fluid that bathes the brain and spinal cord is stirred into activity. Remember that our spinal cord and brain are entirely HE above X-ray photograph of an ex- treme case of fallen abdominal organs. When compared with the normal position diagram at right, shows how the large bowel collapses upon itself through lack of proper exercise, creating creases and wrinkles that clog the abdominal passages and often cause acute illness by the accumulation of waste surrounded by this cerebrospinal fluid. Exercises such as suggested in this article, stimulate the normal activity of this life fluid in the brain and spinal column, thus helping to banish dis- ease, strengthen resistance, and increase our good spirits and efficiency. f VERMIFORM APPENDIX

Page 27

ithly eTrson your angle hem, ten r ing your e is pon | by t is nts hat in- dy, of ood dy, | in on- not ced r- March, 1923 Mammoth Stadium Will: Hold Babe Ruth’s Longest tj - am ¥. Fr. Os 41 This modern i pica the Imperial Stadium at Wembley accommodate 126,000 spectators —80,000 more than did the ancient Roman Colosseum, shown in ruins at the right Park, near London, wil for centuries as the greatest amphi- theater in the world for the presenta- tion of sport spectacles, is to be dwarfed by two huge modern stadiums, one of which will accommodate three times as many persons, while the other will have twice the capacity. They mark a double climax to the two decades that have passed since dedication of the Harvard Stadium in 1903, and that have witnessed construction of the Yale Bowl, the monster stadium at Ohio State University, and numerous other outdoor theaters for the athletic spectacles of which the American public is so fond. The greatest arena of modern times will be England’s Imperial Stadium now in construction at Wembley Park, near Lon- don. It will accommodate 126,000 persons, all of whom will have a clear, unobstructed Te: Roman Colosseum, which stood view of the playing field, although only 35,000 will be seated. In actual seating capacity this British amphi- theater will be surpassed by the new American League baseball stadium in New York, now nearing comple- tion, which will seat 85,000 persons for baseball games, and perhaps 15,000 more for football, fights, or other athletic exhibitions. The Colosseum, most famous of all structures used for gladiatorial spectacles in the days of Rome’s glory, accommodated about 45,000 spectators, according to estimates, although not more than 30,000 were seated. The new Wembley stadium, which will be the center of all great English national ath- letic contests, and perhaps the site for the Olympic games, will cover 2% times as much ground as the Colosseum. The outer wall will be half a mile in circumference. The American League stadium, seating more spectators than any structure in the world, will cost $2,000,000. The field alone would hold two of the arenas in which gladiators amused the Roman public in ancient days. ; iveaa ft kt ted hep ht po, 439 Ye FEET No chance for Babe Ruth to knock a ball ‘‘out of the lot’’ in the new baseball stadium of the New York Yankees, shown above. ~~ BABE RUTH'S LONGEST HOME RUN This is now the greatest of modern amphitheaters, seating 85,000 spectators for baseball games and 100,000 for other athletic contests

Page 28

Popular Science Monthly Improved Photo Sculpture Creates Masterpieces English invention by which a specially taken photograph is reproduced in bas- relief on alabaster, ivory, or wood, have been made since the photo sculpture ma- chine was first described in the October issue of POPULAR SCIENCE MONTHLY. By increasing the accuracy of the process, the new improvements have achieved astonish- ing perfection in detail, as shown in the photo bas-relief on this page. It will be remembered that in the method described in POPULAR SCIENCE MONTHLY a beam of light is projected from a magic lantern on a person’s face or on a statue to be reproduced, a lined glass plate being used in the lantern in the place of an ordi- nary slide. This glass plate projects spiral lines, like those of a phono- graph record, on the subject to be reproduced. A photograph of the subject is then taken, and on this photograph the spiral lines appear. From the negative, a print is made on opal glass, which is used to guide the carving machine. Deviations of the spiral lines govern the movements of the cutting tool and so reproduce the photograph in bas-relief. Glass Negative Guides Tool The improved machine works on a similar principle, except that parallel lines instead of spiral lines are used, while instead of the opal glass print, the glass negative itself can be used to guide the cutting tool. Mounted on a massive, sloping bed plate, the new sculpturing machine is op- erated by two electric motors. A horizontal motor drives a sliding frame that carries the carving tool and moves on a horizontal plane over the material to be carved. The other motor, mounted above the cutting tool, rotates it at high‘speed. A two-handled control shaft is geared both to the vertical shaft on which the GS lEneiish inve simplifications of the cutting tool is mounted and to the sliding frame, which carries a pair of micorscopes. After a negative guide plate con- taining parallel guide lines is made, the sliding frame is swung upward, and the negative plate is clamped to the bed plate, and the material to be carved is also held firmly by clamps. The sliding frame is then lowered and the vertical motor started, causing the drill to rotate at high speed. The horizontal motor then is started and the frame begins to move from left to right. By manipulating the double- handled shaft, the operator brings the intersection of cross hairs in the mi- S|— L Above is a negative used in carving a sculptured reproduction from a photograph. Parallel lines guide the cutting tool croscope over the end of one of the lines on the negative plate and main- tains it on that line to the end of the cut. Since the microscope and drill move in unison, every transverse de- viation of the line from the straight results in a deeper or shallower cut of the drill. The operation is repeated on every line. Making Bronze Bas-Reliefs ing machine The ‘remarkable _ bas- relief, at left, from a photograph by the improved sculptur- own above, gives evidence of the beauty and precision of the new process carved NEW small thresher that sells at a price within easy reach of the small grain farmers, should prove a great time saver, for with it the farmer can follow up the reaper, thresh his grain immediately, load his wagon with the grain, and scatter the straw Small Thresher Saves Time for Farmer about the field to be plowed under as fertilizer. A tractor draws the thresher about the field and the grain wagon is hitched alongside. Should it be desired to save the straw, the machine can be operated as a stationary engine. At the end of each cut, the drill is raised, the motor reversed, bringing the frame back to position. For a bronze bas-relief, a plaster cast of the machine carving is made, upon which the metal is electrolytic- ally deposited. Radioactivity of Bottled Water Is Negligible yore of the foreign or domestic com- mercial bottled water sold to con- sumers on the claim of radioactive content really contains sufficient radioactivity to warrant its purchase, according to the re- port of investigations completed by the water and beverage laboratory of the United States Department of Agriculture, Washington, D. C. In the examination of 46 samples from 15 states and eight foreign countries, the bureau found the highest quantity of radio- activity of a temporary nature in a bottled water from Massachusetts. The largest amount of permanent radio- activity was in a sample from a deep well in Ohio. It was found, however, that it would be necessary to consume 2810 gallons of the Massachusetts water, or 1957 gallons of the Ohio water daily to obtain an efficient dose of radioactive salts. During the tests radioactivity of samples was determined by means of electroscopes. Law Marc

Page 29

March, 1923 43 Secrets of Successful Auto Driving How to Shift Gears Noiselessly—Other Useful Tips from an Expert By Harold F. Blanchard H many automobile drivers are satis- ithly fied with the way they shift gears from high to second or from second to low? Do you know how to make the most effective use of the appliances on the dashboard and of the levers at your side? And do you know how to safeguard yourself and your car against the chance of accident—a disturbing chance that continually hovers over the aver- age motorist (whether he is aware of it or not)? There are a hundred and one little tricks of successful driving that a veteran motorist learns, sometimes by bitter experience; and it is my purpose this month to pass some of these tips along in the hope that they may steer you away from common pitfalls and so increase your enjoyment and safety in driving. Can You Shift Down? First, consider the gearshift. Most motor- ists can slide from low to second and from second to high without a clash and without interrupting the motion of the car; but when it comes to shifting down—that’s quite HIGH I-2 2 NEUTRAL ae another matter. In fact, it’s one of the most difficult problems of successful driving, par- ticularly in hill climbing, and one that com- paratively few drivers have mastered. The steeper the hill, the more difficult the problem the becomes. in- Right here I want to let you into a secret he of gear shifting that has worked so success- be earn ja fully for me and for others who have tried ff se eon NO “ill it that it is worth passing on. I learned ‘et le- this secret from a motorist whom I met UNIVERSAL JOINT ht back in the hills of Vermont, and it’s so an of simple, the wonder is that everybody Move the gear ed hasn’t tumbled to it. lever with assur- Until I struck some of those grueling pa gg t a Vermont hills, I hadn’t given much thought . psn na lies to uphill shifting. Like the majority of motorists, whenever I had to make a shift is down, I shut my eyes, gritted my teeth, and ee —_ ered ' yanked the lever. Sometimes I made a lot ’ ‘i deste F of noise, which I. knew meant that I was Here’s What Happens When — pg eg r chipping little pieces off the gear teeth; and You Shift Gears B, often I lost considerable momentum. But : : ee ats ; 7 “a on those terrific back road hills it was a — picture and diagrams ahove illustrate drive shaft, which is square or splined. Splines question of quick and sure shifting, or the a whee ny SE i pes are simply keys integral with the shaft. risk of breaking ated neck. In short order Shifts, The main numbered diagram shows the For high gear, 2 is moved forward and engages I learned how to shift quickly, but T'was entire transmission gear mechanism as assem- gear number 1. Thus the clutch shaft and the still noisy about it, until I was taught the hJeq in the ordinary car, while the small dia- drive shaft rotate as one, and “direct drive” is simple trick, which is this: grams, numbered correspondingly, show the obtained. Sree? the E hen Sh me positions for ne pe cage Ei - “ i Pee . = ] } ar 1 is connected with the rear end o e or second gear, 2 is moved back into mes 4 - the ngine—t sit ift clutch shaft and always rotates with it. Gears with 7 and Gauuens passes through gears 1, 8, Suppose you’re climbing a hill that is a 2 and 3 are mounted on the main shaff, whichis 7, and 2. . ; i i d through a universal with the drive : little too steep for high gear. When you Connecte ough a di For , at a h with ‘ are about halfway up, you realize you must shaft. Gears 4, 6, 7, and 8. are mounted im- or low gear, 3 is moved forward to mesh wit : : a alls | movably on the countershaft and always ro- 6, and the power passes through gears 1, 8, 6, 2 shift to second, The throttle is wide open, tate with gear 1, while gear 5 is mounted onits and 3. 2 You know, in general, that to make @ own little shaft and is always in mesh with 4. ; ‘ silent shift from high to second, from second Gears 2 and 8 are the “sliding gears” that are For revérse,-3 is moved into mesh with 5, and i died to low, or from high to low, you must in- crease the speed of the engine approxi- mately to the rate demanded by the lower gear. But how? Here’s the answer: Hold the throttle w‘de open and depress the clutch just enough to allow the engine to speed up the desired amount—THEN SHIFT. You can perform the entire operation in almost the time it takes to snap your fingers. You can’t go wrong, and if you judge your engine speed with even fair ac- curacy, your shift will be absolutely silent. The clutch is out for such a brief instant that the loss of momentum is negligible. I have shifted from second to low by this moved by the gear lever. They slide on the the power passes through 1, 8, 4, 5, and 8. method on a 80 per cent grade without noise and with no noticeable loss of speed. If a down shift must be made on a slight up grade, down grade, or level, you need not open the throttle wide. A good rule is to hold the throttle pedal just where you have had it. In shifting from high to low, remember that the engine must be sped up much more than if you were shifting from second to low. Also remember that while 20 miles an hour is a moderate speed on high, it is a terrific speed on low. It is entirely safe to shift from high to low at from 15 to 20 miles an hour, provided you speed the engine up enough. In any case, too much engine speed is better than too little. I’ve observed that many drivers, when shifting upward, are puzzled as to what to do when they wait too long, missing the gear. After trying to effect an engagement by clashing, they stop the car and start over again. There is an easier method. If you’re shifting from second to high, for

Page 30

44 example, and miss high, immediately slip the lever to neutral, engage the clutch, and speed the engine up to a point somewhat beyond that demanded by high gear; then shift as if nothing had happened. Logical, isn’t it? ; Similarly, if you’ve been coasting down a long hill with shift lever in neutral and engine idling, when you get to the bottom, speed the engine up above the high gear rate before shifting. Unless you do this, you may have a ‘“‘mud hook,” is made just for the purpose. It is of metal, with a broad base that is chained to the tread of the tire. Mounted crosswise on the base is a metal cleat two inches high. With two of these hooks on each rear wheel, your car can walk out of almost anything. To get through a short stretch of deep mud, or even a single deep puddle, just “keep going,’ usjng second or low, as Popular Science Monthly race driver, and some of the most dangeroug rides have been with motorists who thought they were being “‘careful.”” I believe there is no such thing as an unavoidable ac- cident. True, there are plenty of accidents in which two cars are involved in which one driver is absolutely innocent; but never have I found a case where both drivers really did everything in their power to avoid an accident. Doesn’t the appalling increase in automobile acci dents emphasize the need of trouble engaging the gears. If you coast down a hill with lever in neutral and At the Wheel— What to Do and How to Do It education for the driver? _ Let’s consider a few in- engine shut off, there is no way of getting back into gear so that the momentum of the car may be used to start the engine. The engine must be brought into motion with the electric starter. When Engine Is Shut Off If you wish to coast with engine shut off and yet do not wish to use the starter, be sure to leave high gear en- gaged, coasting by holding out the clutch. At the bot- tom of the hill engage the clutch gently, with the switch on and the throttle closed, so as not to strain the mech- anism. In using the engine as a brake, it makes little differ- ence whether the switch is on or off; but if you run with it off, be sure to keep the throttle closed, not only to Choke Light Switch = ee aw ° owe (pa i+ (@™* (4m SPEEDOMETER AMMETER A t yea 1G LIGHT SWITCH SS oe — GEAR LEVER Don’t forget to push the choke in after the engine has started; otherwise the engine will suck in raw gasoline that will prevent proper lubrication. NITION SWITCH EMERGENCY BRAKE stances where accidents might have been avoided easily: “A” swings around a cor- ner at a fair rate of speed while a _ pedestrian walks into his path. . Instead of slowing down, ‘‘A’”’ presses the horn button to shoo the man out of the way; but the horn fails him. Local Rights of Way “‘B” approaches a road in- tersection at a fair rate of speed. He has the lawful right of way. But at the same moment another car, piloted by a stranger who doesn’t know the local law, approaches on a side road, “B” stands on his rights and there is a collision. “C” drives 15 miles an hour — the lawful speed — down a street crowded with save fuel, but also to avoid muffler explosions when the switch is turned on. When driving down a long Ignition hill, use second gear in order Switch to keep your brake linings Ammeter from burning. This advice applies to all cars with service and emergency brakes acting on the same drums. Oil Gage If the brakes are on different drums, it will probably be sufficient to use the brakes Speedometer alternately for about an eighth of a mile at a time. On the Ford, use the service Gear Lever brake and reverse pedal al- ternately. E mergency Brake Mud a Cause for Worry Spark Don’t attempt to drive on snowy or icy roads without chains applied to the rear wheels. Look out for slip- Throttle pery, muddy hills in travers- ing unknown side roads in a mountainous country. When driving on unknown : roads, mud is really the only oer thing to worry about. Sand mene or stones or severe bumps all may be negotiated success- Be sure to turn lights off when you put the car away. Never leave headlights on when the car is standing, but have at least one light burning front and rear to prevent collision. When you attempt to start the engine, be sure to turn the switch on all the way. Form the habit of watching the ammeter mea- suring the current from the battery. When it fails to work, find out why as soon as possible and avoid battery trouble. Watch the oil pressure gage. Operating the engine when the gage.fails to register will usu- ally result in burned out bearings. Be sure that your speedometer is accurate. At least twice a year ask some motorcycle officer to pace you for a hundred feet or so. Before starting the engine, always be sure the gear lever is in neutral. After the car is under way, try the emergency brake to see that it is off and so avoid burning out brake lining. Drive with spark fully advanced, retarding it only to prevent knoéking when the throttle is opened wide with engine running slowly. Re- tard spark half way when cranking. Open the throttle from one eighth to one quarter for starting. Never ‘drive with your horn.” Don’t depend on it. It may fail you when you need it most. When the thermometer indicates an overheated engine, get out and see what’s wrong. playing children. One of them gets in his way. He tries to stop, but it is too late. . Ten miles an hour would have prevented the accident. “D” is running 40 miles an hour when his right front tire blows out. The steering wheel is jerked from his grasp and the car turns over. A tight hold on the wheel would have prevented the accident. Horn Prevents Disaster “E” is driving at a mod- erate pace along a country road. He dims his lights for an approaching car and then runs over a man walking at the side of the road. Blow- ing his horn at the moment would have prevented the calamity. It must be admitted that better brakes might prevent a large percentage of accidents. The braking equipment on most cars ig sadly deficient. But it is difficult to imagine an accident that might not have been avoided by exer- cise of caution. fully, even though some time may be lost; but it takes more than slow driving to combat deep mud. Chains will be required on the front wheels for steering, as well as on the rear wheels for traction. If no chains are available, remember that any farmer can supply you with hemp rope from three quarters to one inch in diam- eter, which will serve the purpose. In the deepest mud even chains and rope are useless, but a special device, known as required. If the car stops, don’t spin the wheels, or you are likely to get mired to the hubs. Back out of the mud gently but firmly. Then take stock of the situation. Detour if you can; put on chains, ropes, or mud hooks if necessary; inspect the road for an easier path; and, finally, if you must follow your original tracks, do so with all the speed you dare. If you stop again, back up and buck it again, and so on. The safest ride I ever enjoyed was with a The trouble is that most motorists drive with little or no “factor of safety.” If this term is new to you, I might explain by saying that an elevator cable is usually made 10 times as strong as the calculated maximum stress; thus the factor of safety is 10. In machines where life is not en- dangered by possible breakage, it is usual to allow a factor of safety of five. The factor of safety is a necessary precaution to allow (Continued on page 45) gall for has tha ing

Page 31

ous ght ere ac- nts one ver ers ing eci | of in- nts led Or- 2ed lks of ses the out ine 10t er- ive his by lly ty n= or ow March, 1923 Novel Auto Accessories for Safety and Comfort The neck of this 214- gallon folding bucket for filling the radiator has an automatic valve that opens when rest- ing on radiator pipe A newly devised spring hinged gasoline tank cover cannot be lost and provides added safety against explo- sion by releasing va- pors generated by ex- cessive heat Because this windshield, against which a motorcycle rider was hurled, was of a new type of non-splintering glass, the occupants were uninjured A new leather spring cover contains an oil hole equipped with dustproof spring cap, and provides efficient lubrication (Continued from page 44) for flaws, lack of uniformity in the strength of material, unexpected stresses, wear, and rust. But most motorists drive as their whim dictates. They fail to make allowances for lack of experience, lack of alertness, unfamiliarity with the roads, recklessness of other drivers, faulty brakes, or un- expected developments. As long as conditions remain ideally favor- able, they skim through, but sooner or later they run _ into trouble. It is advisable to be twice as careful as you think you ought to be, simply because it is impossible for any human being to be fully alert every instant that he is behind the wheel. No matter how good a mind he has, it will wander. Hence the constant need for alertness as a factor of safety in driving. To maintain a proper factor of safety at all times, we must view our driving pessimistically. When on the road we see a smashed car and its victims, we are kidding our- selves if we say, “That will never New priming cups, mounted on four special head bolts and installed in an hour, facilitate starting of Fords ‘TO CARBURETOR ve The Vacuum Tank HE function of the vacuum tank is to draw fuel from the gasoline tank and deliver it to the carburetor, utilizing suction from the intake manifold. The tank incloses two chambers, a float, and valves. In the upper chamber are intake pipes connecting with gaso- line tank and intake manifold, while an outlet pipe in the lower chamber runs to the carburetor. When the float is at the bottom of the upper chamber, as in dia- gram, the valves controlling the gasoline pipe and suction pipe are open, and the upper chamber fills with fuel. Thereupon the float rises, closing these two valves and opening an air vent. The fuel then flows through a one-way flapper valve to the lower chamber, thence to the carburetor. As the upper chamber is emp- tied, the float drops and the cycle is repeated, This instrument simplifies headlight focusing by projecting the rays on a ground glass screen happen to me.” We should never think of taking a chance if we thought that we might suffer for it the very next instant. The atti- tude that we can take a chance once in a while and get by with it is wrong. Just as wrong as that of the motorist who believes in his luck. We can’t monkey with the law of averages and get away with it. The more chances we take, the surer we are of having an accident. The only way to be safe is to drive always with’ an extra dose of caution. I’ve found that it takes imagi- nation, experience, and unending alertness to drive safely mile after mile. In order to drive safely, we must learn to recognize crises of all sorts far enough in advance to take whatever steps are necessary to avoid them. New drivers will do well to be especially cautious until the trio— imagination, experience, and alert- ness—are fully developed. Finally, here’s a mighty good rule to follow: Never outdrive your headlights or your brakes. ——— nee Ronee Sete ene re 9 ea an ce law FE —_ av wetaewer™

Page 32

46 rt — . 4 = i - =. ee te, x ne *. A vast web of suspended airways, hung from cables high above the tops of city skyscrapers, is proposed to carry rapid transit railways on two levels Proposes Suspended Railways to Bridge Cities! ONFRONTED with traffic problems © that seem beyond solution under present conditions, faced with ever increasing streams of automobiles, and im- pressed with the need for ade- tures now in use. Lafferty includes in his plan a motor speedway at a much lower level, under the airway—a plan that is directly in line with that proposed by Popular Science Monthly

Entrances would be by elevators running through towers Richard Enright, New York police com- missioner, in the hope of relieving the terrific congestion of automobile traffic in America’s greatest city.

quate rapid transit, authorities of greater American cities, especially New York, are des- perately trying to find some way to meet the situation. How will these critical prob- lems of transportation be met eventually—on the surface of our streets, underground, or above us? An Expert's Prophecy Gustav Lindenthal, designer of the world’s greatest railroad arch bridge and of the colossal suspension bridge that will span the Hudson River, de- clares, in a signed article on the opposite page, that the cen- tury in which we live will be the final chapter in the greatest era of iron bridge construction in history. Is it possible that the last word in suspension-cable steel bridges will be a vast network of hanging airways, carrying trains of an aerial rapid transit system high over skyscraper roofs out to the commuters’ suburbs? , Just such a system of aerial transit actually has been pro-

jected by R. C. Lafferty, New : York engineer, and is now being considered by the New York Transit Commission to supplant, to some extent, the subways and elevated struc-

Three of ihe World’s Greatest Suspension Bridges patiebeneneocenenennne SPAN 1596'-0" SADDLES

CABLES ANCHORED BY STEEL PROPS AND IRON DEAD MEN EMBEDDED IN CONCRETE

econ «ae

CABLES ANCHORED BY — MASSIVE BUTTRESSED castes FIKED ‘SPAN 1750'-0 APPROACH BUILDINGS L TOWERS BEND AS CABLE

LENGTHS VARY nit) H ee l a nniill | iitutit ————— em On ete DPD ELI hs ORL Tal hacen PRR N ne ice Nic ie tok ok ee ROR RE RO RD RD RY i => Z Cees rom ia ie ee rene: STEEL rowers

CABLES ANCHORED BY ra 1 aeadied IMMENSE STEEL PROPS CABLES FIXED ” TOWERS ROCK ON BALL AND SockeT CABLES FIXED AND DEAD MEN EMBEDDED | BASES AS CABLE LENGTHS VARY (N CONCRETE | m |

ie eee ° alg’ i <@ A iat MASSIVE STEEL TOWERS ee py 9: These diagrams show the construction of: Top: Brooklyn Bridge, connecting Manhattan and Brooklyn. Center: Philadelphia Bridge to connect Philadelphia and Camden. Bottom: Detroit Bridge to link Detroit and Canada

“The 1 cities is ahead,” § 1920 we | than in | automob and 33 | 39,210 at pus Cire hour pe grown t¢ “We ‘ mobiles, three ye: the pric W. C. | cheaper crease W “Traf Americz culties | increase waterfr of ever channe Com Enri stretch Island side st of aut even h of incr for ad Lafi stallat viadu transi unsig} Chica pylor dista swun the r two « long elimi | by h abov car 1 rail and pow grip wou whe Ss pen

Page 33

onthly i ould ators ough -om- the c in | March, 1923 “The trouble with most of our large cities is that they have failed to look ahead,” says Commissioner Enright. ‘In 1920 we had 50 per cent more automobiles than in 1916. The estimated increase in automobile traffic this year is between 30 and 83 per cent. In 1919, for instance, 39,210 automobiles passed through Colum- bus Circle, New York City, within a 12- hour period. Today that number has grown to about 70,000. “We are doubling the number of auto- mobiles, by conservative estimate, every three years. And, with Henry Ford cutting the price of his automobiles and men like W. C. Durant predicting the day of still cheaper automobiles, it is likely the in- crease will go on at an even greater rate. “Traffic congestion affects every one in America, not only in discomforts and diffi- culties he encounters in his own city, but in increased cost of living. Congestion at the waterfront in New York adds to the price of every article that passes through the channel of that waterfront.” Commissioner Enright’s Proposal Enright has proposed long viaducts, stretching half the length of Manhattan Island on both sides, with ramps leading to side streets at long intervals, to take care of auto traffic and relieve congestion. But even he admits that this does not take care of increasing pedestrian traffic nor provide for adequate rapid transit. Lafferty’s plan makes possible the in- stallation not only of Enright’s proposed viaducts, but also of airways for rapid transit. He would eliminate the present unsightly elevated structures of New York, Chicago, Boston, and Philadelphia. As supports for his proposed airway, Lafferty proposes to use strong steel braced pylons, or abutments, set into bed rock at distant intervals. Strong suspension cables swung between these pylons would support the roadbed. He provides for four tracks, two on an upper deck, on which would run long cylindrical steel cars. He would eliminate excessive wear and tear on cars + by having them run on monorails, one rail above the car and the other below it. The car would be supported on the lower mono- rail by a large bearing wheel at each end, . and would be driven by small horizontal power wheels forced by compressed air to grip the track from each side. The car would be held upright by means of, idler wheels running on the upper tracks. Since it would be unnecessary to de- pend on weight for traction, Lafferty’s proposed car would weigh only 20,000 pounds, as compared with the 88,000- pound subway car of the same capacity, now in use. Entrance to the airways would be by elevators running through buildings situ- ated at street corners, where pylons sup- porting the suspension bridges would be placed. This feature, of course, would eliminate the present ugly stairways to elevated roads as well as the kiosks for subways. 47 Below is shown the proposed method by which long, cylindrical cars would run on monorails of an aerial railway. Traveling on single wheels, the car would be propelled by smaller power wheels gripping the lower rail — BEARING WHEEL bY hate this century will pass the age of iron suspension bridges. We are about to reach the furthest advance in the art of bridge building we shall ever know. Indeed, the Hudson River Bridge project, most stupendous struc- ture ever proposed, may mark the ulti- mate in bridges. Although the twentieth century will go down in history as the great era of steel bridge building, there is little doubt that the year 2000 will see the end of these projects. By that time iron will have become too costly, because of the dimin- ishing supply of iron ore. We can look back. to the time when a suit of armor was almost worth its weight in gold or silver. We cannot see far enough ahead to predict that iron will again become such a costly product, but we do know that it will cost too much to Close of Greatest Iron Bridge Era Is Near By Gustav Lindenthal, Designer of the Hudson River Bridge be used in great quantities for bridge building. Only a century ago the age of iron bridges began. From the early simple bridges of iron were developed the greatest structures of the present—the Brooklyn and Williamsburg suspension bridges, the Firth of Forth cantilever bridge, and the Hellgate bridge, the greatest railroad arch structure the world has ever known. Railroads today are building the finest bridges. Within the past 10. years the price of steel has almost doubled. The available supply of iron in the world is slowly but surely decreasing. There may be improvements in the uses of newer materials for some parts of bridges, but in the main it is safe to assert that we are about to say the last word in iron bridge building. fein tise eR -a-= aalennane neuen We ie, The projected suspension bridge across the Hudson River with central span nearly three quarters of a mile long. Its designer, Gustav Lindenthal (at right), says it may repre- sent the highest possible limit the world will ever see in iron suspension bridge construction © Paul Thompson — 3 Chines =O pp ne

Page 34

48 Stepladder Folds into Small Space NEW ocol- hapsible, rigid stepladder is a valuable addition to household ac- cessories. The ladder has a skeleton frame of wood fastened to- gether with nickel - plated steel catches. Each step is of two pieces hinged in the center and, when in use, is supported = at the center by steel braces. The top step is protected by guards. The ladder folds into 234 by 714 by 52 inches. nae wancedeesetee eS This rigid step- cashed ladder, when folded, can be hung on the back of a door, as shown be- Mercury Circuit Breaker Controls Pressures A GLOBULE of mercury inside a glass bulb filled with an inert gas is being used to control pressures by making and breaking electric circuits. The tube is usu- ally attached to one arm of a Bourbon tube. When the pressure increases, the tube tends to straighten out and the action shifts the mercury from one side of the control tube to the other. One or more elec- trical contacts locat- ed within the tube dip into the mercury when the liquid is in certain positions. As the mercury slides back and forth in agreement with the movement of the Bourbon tube, the electric circuits are made and broken. The tubes have been made for pressure differences of .2 of an ounce, and will handle electric currents of 10 amperes at 110 volts. Because of the inert gas that instantly kills any tendency of the mercury to arc, the little tubes are said to have a long life. How mercury opens and closes circuit Writing on ‘‘Everlasting”’ Pad Disappears N “EVERLASTING” tablet for mem- oranda, recently invented, consists of a rectangular sheet of metal, with edges bent over to form a frame, and coated on the upper side with a black composi- tion of waxlike consistency. Over the black coating is a sheet of very tough tracing pa- per, held in place by a metal strap across the top. Memoranda are written on the tracing paper with glass pointed stylus. As long as the thin paper remains pressed against the black coating the letters formed by the im- pressions of the stylus are visible; but when the paper is lifted away, the writing per- manently disappears. Popular Science M onthly British Learn French by Radio from Paris oy gaat persons in London and vicin; are learning to speak and understgy, the French language as the result of the broadcasting of music and speeches the Eiffel Tower in Paris. Thousands gf British citizens listen in. Most of the London department stone are selling a cheap standard receiving gg from which good results are obtaij Hearing the spoken French over the ragiy and supplementing this with textbook study, makes it much easier for students ty understand and speak the language. Electrical Sealing Device Eliminates Fire Hazard T HE recent invention of an electric geal. ing machine marks the first important improvement in methods of applying seal. ing wax since King Solomon’s time. The March, 1 new appliance eliminates the fire hazard olny that accompanies the present crude method of heating the oo wax over a flame, , as well as effect- ing an appreci- : able saving of of wh time, wax, and import postage. route f The wax is extend placed in a con- contin tainer, where it ube m is melted by poe means of an elec- canal tric heater. Plac- platea ing the machine and t over the spot . Th where the seal is nas to be, and press- nalizi ing a small lever — releases a small Electrical sealer. i amount of seal- showing wax heat- onth ing wax. Pres- ing pot sure on the seal =o handle brings the seal down on the melted Ulm. wax, completing the operation. the ’ The New York concern that manufac- -— tures it claims that the new sealing machine! 7 effects a saving of 50 per cent in wax, 50 for t per cent in time and 20 per cent in postage. pepe The additional expense of the electricity “= consumed is comparatively small—one half: P a cent an hour for continuous operation. bi Mar end lift and camping utensils, which can be attached with a thumb- clamp to im- provised han- dles, have been invented recently by a Canadian— William J. Feldkamp, of Brant- ford, Ontario, to save packing space and weight—serious prob- lems for all campers. Handles may be made at the camping site from split or forked | sticks and attached to the uten- sils—fork, spoon, toasting spit, or pancake turner—by means of a ANDLELESS “ = Handleless Camping Utensils Save Space | clamp operated by a thumb- screw. When the time comes for breaking camp, these han- dles may be thrown away.

Page 35

paler, heat- melted anufac- nachine} vax, 50 ostage, ' ctricity ne half: tion. nb- for an- wn March, 1923 Elevator Locks to Lift Barges over Dry Plateau 49 To carry boats through the pro map), 26 massive counterweight ESPITE unsettled industrial condi- D tions, engineers in Central Europe are planning the _ construction of what will be one of the world’s most important artificial waterways—a water route from the North Sea to the Black Sea, extending 2100 miles across the European continent, and linking the Rhine and Dan- ube rivers in Germany. Tremendous en- gineering problems are involved, for such a canal would have to traverse the Alb plateau lying between the upper Danube and the Rhine, at a height of 1830 feet, in a region where water is scarce. The scheme involves the ca- nalizing of the Neckar River,a FF. tributary of the Rhine, up to Plochingen, Wiirtemberg—a point 35 miles distant from Ulm _'000 onthe Danube—and anextension 6507). _____--- on canal between the Rhine and Danube (see ift locks like that shown above would be required wait Entering the lock, the boat floats in a water-filled trough suspended on cables that pass over drums at the top of the lock. The elevator trough is lifted by counter- 1650 | traversed by 1300. from the Rhine to Showing the tremen- oe dous grades to be ‘Ky canal the Danube hen et +. 27 PLATEAU AND CANAL weights and electric motors the lower gate is closed, im- prisoning the boat and sufficient amount of water to float it. Power is then transmitted to the endless chain for the lifting. The counterweights are sufficient wecnne RIVER ee —— to balance the trough and its of navigation up the Danube to 300 4. load so that just enough power Ulm. Between these two points ell the canal would have to be car- ried over high plateaus by systems of locks. The absence of an adequate water supply for the operation of locks involves the most serious problem, which engineers propose to solve by using immense mechanical lifts. Twenty-nine of these lifts will be required since the plateau rises nearly 1500 feet above the Rhine end of the waterway at Mannheim and 300 feet above the Danube end at Ulm. The proposed counterweighted lift lock is a massive structure of concrete and steel, capable of lifting 1200-ton boats 50 100 150 200 MILES 86 feet. The elevator consists of a trough filled with water in which the boat floats. This trough is suspended from the structure by wire cables that pass over drums at the top and are attached to counterweights. Electric motors, operating endless link chains, supply the power. To elevate a ship the trough is brought to the lower level; then a safety mechanism opens the lower gate. The boat is drawn into the lock by means of a cable operated from within the lock and when in position 300 is required to overcome friction in the operating parts. When the trough has reached the upper level, the safety mechanism again allows the upper gate to be opened and the boat is free to continue its journey. Thus the water is conserved in the upper reaches and there is no danger of the canal running dry. It is estimated that 50 ships could pass through the canal daily. This canal would be as important as the Suez and Panama canals, for it would provide a short and cheap route from the North Sea to the Mediterranean and the East. Fortune for Inventor Who Saves Mountains of Grape Pulp ORTUNE awaits the man who discovers a profitable method of con- verting into salable jellies, cream of tartar, oils, and extracts the enormous quan- tities of grape skins and pulp wasted each year by grape juice factories. Reports of the Depart- ment of Agriculture show that the average quantity of grapes crushed yearly for beverage purposes in the five years ending in 1918 was 22,000 tons. Of this Photo courtesy U. S. Department of Agriculture More than 4000 tons of valuable grape pulp is wasted each year at grape juice factories in piles like this amount 660 tons was dis- carded as stems and 4400 tons as wet pulp. From the stems it would have been possible to obtain 13.2 tons of cream of tartar. The seeds in the pulp would have yielded 89.3 tons of oil and 526.7 tons of oilcake. Even the hulls would have added their share in the form of nearly 50 tons of tannin extract. Experts estimate that 8300 tons of wet grape skins goes to waste annually. ee —_J

Page 36

50 Mysterious Birthplace of Popular Science Monthly Eels at Last Discovered

Pa found in our rivers.

Of a; “ Fo iene : ‘ i ’ wR Pe ee

Here are typical American eels such as are The chart below shows the newly discovered breeding ground for eels, with the progressive sizes of the larvae at stages of their journeys to the American and European coasts

a * sf

Photo courtesy N. Y. Zoological Society

7 HERE doeelscomefrom?” This apparently simple question has for many years excited the curiosity of scientists. Strange to say, the eels familiar to us in aquariums and museums have been a complete mystery to naturalists. Nobody had been able to find baby eels. No- body knew where they were born. The grown eels appeared mysteri- ously along the coasts of Europe and America, and disappeared just as queerly. Where did they come from? Now, a Danish zoologist, Dr.

No Lareneonfeund more fon .6inch long Actual hatching ground No larvaeare found more than 1.8 inch - ATLANTIC esenaleg aid _ selting out or breeding Larvae less than inch

L. Achual hatching ground AMERICA Larvoe kess thon #1nch A difficult problem confronted Doctor Schmidt when two species of eels, the European and Amer- can, differing radically when full grown, were found together at the spawning grounds. How did the newly born eels know whether to start for Europe or America? Since the journey to Europe takes a year longer than to America, Doctor Schmidt concluded that those European larvae which started for America, arrived there too soon, before they had grown

sufficiently to reach the stage where they could live in fresh water.

Johannes Schmidt, after years of research, has returned from an adventurous ocean voyage with the report that he has discovered a breeding place near the Ber- muda Islands, in the Atlantic Ocean, from which all the eels that inhabit the waters of our rivers have migrated. In 1904 a small transparent leaflike fish about two inches long was captured off the north coast of Scotland. Doctor Schmidt concluded that this was the larva of the common eel found in European waters. He set out in a small ship and fished all over the Atlantic Ocean, charting as he went, following trails which led him to the capture of smaller and smaller larvae, until he finally reached their breeding grounds. How the Eel Develops The history of the eel, as discovered by Doctor Schmidt, shows that the larvae during their first year gradually move away from the breeding zone, and by their third summer are off the coastal banks of ~ Europe, in the case of the European eels, where they are about two inches in length. Then a strange change takes place, for the larva shrinks in width and length, becom- ing round instead of flat. It is then known as an elver, and begins to ascend rivers into fresh water, where it lives and ‘feeds for from six to 20 years. At some time during this period the reproductive organs suddenly develop, the eyes become larger and the female as- sumes a silvery bridal coat. Then the eel starts its journey back to the spawning grounds. What happens to the eel from the time it leaves the river to the breeding time remains a mystery. However, it is known that the fish never returns after laying her eggs. Therefore they perished before maturity. Similarly, he believes, no American eels are found in European waters because they require fresh water long before they can get it.

Steel Arms Unload Ore from Lake Boats

WO carloads a minute is the rate at which these huge mechanical arms transfer ore from lake boats to freight cars at Ashtabula, Ohio.

Buckets are suspended from long steel plungers, the upper endsof which are — pivoted to walking beams supported by movable trucks on rails

<

Pa ae a ae | dT, ee |

Page 37

March, 1923 51 Science to Salvage Fuel from Mine Waste Piles States, due to diminishing available coal and to unfavoiable industrial condi- tions, is commanding the attention of scien- tists and inventors, who are experimenting with methods of salvaging vast piles of ‘‘coal waste” containing enormous quantities of fuel. The waste at the mines consists largely of slack—fine screenings of coal dust and dirt- culm, an inferior slatelike anthracite, and gangue, or mineral matter found in coal veins. Improvements in heating apparatus that per- mit industries to burn much finer coal than heretofore have aroused inventors to attack waste piles which, until recently, have been considered as not worth the cost and trouble of salvage. Minerals Separated from Coal One ingenious new salvaging machine works on the principle that gangue, particularly that containing iron, may be separated from the coal if brought into contact with a magnetized or electrostatic field. Ts critical fuel shortage in the United FEED HOPPER HARGED 4 iii Sh gaat The process consists first of crushing the coal waste and then sifting out coal particles of such fineness that they would be likely to Species form an explosive dust. An explosive-pre- Amen- venting gas is used also to treat the coal, to en full insure safety and also to remove some of the at the moisture that might retard separation. The As coal mine waste passes through a lid the crushed coal and gangue are then dumped into ‘series of electrostatic fields in this sal- - . vagin machine, mineral matter is ther to the apparatus for separation. sorted from coal by charged electrodes, | From a feed hopper, the mixture drops to a as shown in diagram e takes feed roll that tends to keep the flow slow but oe oe oe ne ea nerica, constant, then to the first of a series of electro- typical of the piles of waste containing | that static fields, where some of the iron-containing vast stores of fuel waiting to be sal- which gangue is charged by electrodes. In passing vaged at our coal mines | there from one electrostatic field to another, the grown mineral matter, as it becomes charged, is re- at the side of the machine oppcsite the the operation makes the separation more where pelled by the charged electrodes and thrown minerals. complete. An alternating current with a water, to one side. Meanwhile, the non-conductive Thus, in one operation, most of the voltage of 15,000 to 25,000 has been found before coal passes undisturbed from one field to gangue particles are separated by repul- __ to give satisfactory results in charging the Ss, no another, finally falling into a container sion from the coal particles. Repeating electrodes. opean j water e e 5 Eyeglasses Fitted on Plaster Casts of Patients’ Noses a B* MAKING plaster casts of the noses nose bridges of all his patients for future Markings are made on the plaster cast of patients who come to him for eye- reference—which is found very useful, par- to indicate exactly where the nosepiece of ‘Ss glasses and spectacles, Dr. Nelson Y. Hull, _ ticularly when filling emergency orders for the glasses should rest. In many cases, of New York City, is able to provide glasses new pairs of glasses. Doctor Hull has found it easier to make 1 that fit perfectly, even if the patient accurate adjustments on the cast does not appear in person at his office after the first visit, when the cast is made. ‘ Since no two noses are alike, the nosepiece of glasses for each individ- ual patient must be delicately curved and adjusted. Some noses are very hard to fit because of unusual con- tour, and for this reason patients have sometimes been subjected to tedious fittings. By using plaster casts, Doctor Hill not only obviates this inconvenience, but keeps permanent records of the On a plaster cast exactly duplicating the contours of a patient’s nose, spectacles are fitted as shown at the left than on the patient’s nose. Cows Thrive on Sawdust {peer cows give just as much | milk when a third of their food consists of hydrolyzed sawdust— that is, sawdust resolved into other compounds by taking up water. The Wisconsin Agricultural Ex- periment station reports as follows: “Two groups of three cows each were fed for 70 days. One group received a ration of alfalfa, hay, corn silage, and a concentrated mixture of 60 parts yellow corn and 20 parts linseed meal. The ration for the other three was the same except that hydrolyzed sawdust, made from Western white pine, was gradually substituted for ground corn at the rate of two pounds of: sawdust for one pound of corn. ‘*When the percentage of sawdust reached 40 per cent, two cows failed to eat the mixture well; but when the proportion of sawdust was re- duced to one third, no difficulty was experienced.”

Page 38

Popular Science Monthly Rainbow Colors Betray Cutting Faults in Tools Stresses 1 in Materials Measured by Remarkable New Apparatus Photos © Popular Science Publishing Co., Inc. How a Good Tool Cuts A sharpened steel tool planing a plate of translucent nitrocellulose in a polar- How a Poor Tool Cuts An improperly shaped planing tool in action. The tool acts as a wedge ized field of light. The color bands in front of the cutting edge indicate variations in radial compression stress in the material, while the bands in the rear measure tensional stress behind the tool. Note that the shaving breaks away at the edge of the tool, indicating true shearing action, as compared with wedgelike action of a dull tool, shown in the third picture HEN you cut a piece of steel or V \ other metal with a dull tool, just what happens in the metal? Every mechanic recognizes the necessity of having keen edges on his cutting tools; yet the exact effect of dull tools on the material—in terms of strain and stress, in splitting and in jagged surfaces—has re- mained a mystery. To obtain scientific knowledge of these facts This remarkable photograph shows the action of a milling cutter, a rotating tool with multiple cutting edges. Since the profile of the cut is a curve, the shaving increases in thickness. Black stress patches in the shaving indicate that it is not sheared off as it should be, but is being wedged and torn off by jerky action of the cutter due to the fact that material under tension elongates, and becomes distorted. Simi- larly, compression thickens the material with corresponding distortion. Thus, a definite pull on a translucent body may be expected to cause a definite distortion, and if light rays are passed through it, the shade and degree of coloring should be in propor- tion to the amount of stress. forced between the shaving and body of material, tearing away the shaving by jerks and producing a rough surface on the material. Note that the im- perfect tool has pared off a second threadlike shaving by a double cutting action. Because of the tearing action of the tool the shavings split away in advance of the cutting edge mous saving of power now wasted by in- effective tools. Engineers will be greatly assisted in attaining “‘the one best way of workmanship.” In the polarized light experiments, nitro- cellulose, a transparent substance, is used. While the material is being cut on a lathe, milling machine or planer, polarized light is passed —— it in the vicinity of the cutting edge. When this light is projected on a —of tremendous value in every modern work- shop — engineering ex- perts of University Col- lege, London, recently discovered a remarkable way of studying the cut- ting action of tools by means of rainbow color- ing of translucent ma- terial under stress, when subjected to polarized light. By this method they have obtained colored photographs, re- produced in black and white on this page, of such materials as they The polarized light used in these experiments was obtained by pass- ing sunlight through a crystal of Iceland spar. A light ray is caused by a vibration in the ether, which moves back and forth across a straight line that marks the direction of the ray. When this ray is passed through Ice- land spar, only those vibrations that strike the crystalline structure longitudinally are permitted to pass, while the other vibra- tions are arrested. The peculiar property of the emerging ray is that all its vibrations are in a single plane. It is known as polar- ized light. The light affects transparent materials under stress in such a way as to produce colors that crdinary light would not reveal. It has long been known that vivid colors are produced when polarized light is passed through a substance under stress. This is appeared during the cutting process. LANTERN screen while the cutting operation is in progress, it is noticed that rings of color precede and fol- low the tool as it plows its way along the ma- terial. These rings are of varying shade and in- tensity and seem to circle about the tip of the tool. Further tests on sta- tionary materials under Translating varying degrees of stress in material under load in terms of rainbow colors, this ingenious apparatus for studying the action of cut- ting tools, explained in diagram below, projects polarized light through the translucent material under observation, and onto a screen. In photo, model was not shown MODEL . UNDER LOAD POLARIZER =} ANALYZER CRYSTAL CONDENSER CRYSTAL ' While such a test can be conducted only on materials light can penetrate, the ex- perimenters have assumed that steel and other metals that must be cut follow similar laws and can be studied “by proxy”’—that is by analysis of a translucent substance. Should this be the case, it will be possible to design tools scientifically, instead of by haphazard guesses based on experience in the workshop, as at present. Photo-elastic measurements will indicate exactly the proper depth of cut that should be made when turning or planing a particular ma- terial and will undoubtedly result in enor- SCREEN known loads have re- sulted in the compila- tion of a color scale by which the colors can be interpreted in pounds of stress. Thus, in a cutting action, a series of concentric circles of color precede the tool, advancing like a rainbow through the material and ranging from black at the tip of the tool to reds that become paler at a distance from the cutter. This indicates that the material is under compression due to the forward motion of the cutter. The black indicates stresses sufficient to break apart the substance. Behind the cutting point is another series of similar circles; but these are indi- cations of tension, showing that as the cutter progresses it still pulls forward on the material being cut. Thus, by compar- ing the colors produced in material by edges of varying degrees of sharpness with the scale, the exact effect of various cutting edges can be determined. Experimenters found that when a dull tool was used, the stresses were enormous, as shown by black fringes about the tool.

Page 39

March, 1923 , 53 i New Low Voltage Tube Makes Radio Sets Simpler — Expert Reports Remarkable Success with Simplified Receiving Outfit. By Armstrong Perry [Oe life for the vacuum tube, be applied to any style of tube outfit. The development in-these low-voltage tubes means not only portable radio enjoy- ment, but it means tubes of longer life; simply because they are cooler the grid, standing between the filament and plate, varies the flow. Connected with the antenna, the grid receives the incoming im- | pulses and uses them to alternately hasten and retard the flow of the greater economy, a more simple and convenient receiving set, and one that may easily be carried about from room to room or to a friend’s house—these things are made possible by the use of the new low-voltage electron tubes that re- quire only a dry cell to light the filament. Despite the whirlwind spread of radio in the past year and a half, there are still literally hundreds of thousands of people who would like to enjoy the advantages and pleasure of having a receiving set in the home, and somehow haven’t got around to installing one. The fact that the electron tube set has required a storage battery for the tube filaments has unquestionably deterred many of these possible purchasers. Not only has the storage battery seemed to them likely to be cumbersome and hard to place in a room, but in addition they have hesitated because of the nuisance of having the battery frequently recharged, and the fear that its acids might ruin rugs. Portable Outfit for Beginners Today these radio beginners may start with a single circuit set and the new low- voltage tube lighted by a dry cell battery of the kind used to ring the doorbell. Of course, when the storage battery can be permanently installed, and can be re- charged without disconnecting or moving, it remains the stand-by of the full-fledged radio fan. It is essential to loudspeaking results with power amplifiers, and sooner or later every radio user gets to the point when he wants to own a two-stage radio set with a loudspeaker, so that all the family and guests may enjoy the evening’s enter- tainment. So it will be seen that the storage battery is still to be reckoned with. But the fact remains that for the beginner who wants a simple and portable outfit, the new dry cell tubes have saved the day. When a well-known concern advertised a receiver using tubes that would operate with only a dry cell to light the filament, and the usual compact and light B battery, heated, throws I was skeptical but hopeful. Ilost no time them off; the plate, in trying out one of them. That wasayear positively charged, ago. For some time the low voltage tube could not be purchased except in connection with a complete set. Now it is available to any one who has the price, and it can between its than the tubes we have been using. Some progress has been reported in designing a tube that will optrate with a cold filament, but to date the incandescent wire seems to be neces- sary for practical pur- poses. There must be a flow of current through the tube without contact internal metal parts, because it is by altering the flow of this current that we get sounds louder than can be produced by using only the current the an- tenna brings in. A crystal detector set, using only the energy brought in from the dis- tant transmitting sta- tion, is limited in its range. The electron tube set, using the -energy from the distant station as a trigger to release many times more energy from a local source, is much more efficient. Electron Tube Principle In order to produce a flow of current through the electron tube, it seems necessary at pres- ent to heat the filament because it will not throw off electrons otherwise. Electrons are the minute divisions of matter that when flowing, make up the electrical current. The filament, when pulls them in, and A two- pon sas comrentey spaced and care- pound dry fully adjusted, are cell does contained inside a the work small hollow cylin- ° ism 40 der that acts as pound storage The new low-volt- age vacuum tube shown above is a marvel of fine and compact work- manship. The delicate grid and ~ the tube plate ae current and thus make it ripple like the waves that radiate from the trans- mitter. These ripples are changed by the action of the phones into sound waves exactly similar to those produced by the speaker, singer, or mu- sical instrument at the broadcasting station. In the ordinary types of tubes that we have been lighting with our storage batteries the fila- ments glow brightly. To heat them to incandes- cence a comparatively large amount of current is needed. Metals dete- riorate rapidly when heat- ed. When overheated, as the filament is when we accidentally make a wrong connection and , Shoot 22% volts from the |! B battery through it, it may burn off in a few sec- onds. At best the fila- ment is shorter lived than Tube Glows Dimly The low-voltage fila- mentis long lived because we wish it were. \ it glows dimly. I took a set using the dry cell tube up to a roof one day, hastily improvised an aerial, and turned on the juice to hear a speech in }j a town 50 miles away. The filament appeared to be as coldly pas- jj . sive with the juice on as it did with it off. _I turned the rheostat knob as far as I dared. No result. Hoping against hope, I put on the phones. # Instantly I began to hear the speech. The ' Sea trouble was with me, not with the tube. I ¥ cmanpere. she sine of the bulky stezngy bet had forgotten the maker’s admonition that § ery in relation to the ordinary high voltage — the filament shines so dimly that in bright ¥, ee we omens oy sunlight the glow of it may not be seen. } ell in relation to the new low vol tube neater (at right) wane Not so long ago I visited a fellow who had })

Page 40

mous, however, on the question of tubes. I asked a salesman who is an expert if he would help me assemble a good low-voltage tube set for a friend. “Yes,” he said; “‘but you’re crazy to get -one. They are not nearly as efficient as the sets that use standard tubes and storage batteries.” This man, whose word I have learned to rely on, was giving me the best advice he could from his point of view. The difference in the evidence emphasizes the fact that different men have unaccountably different _experiences with the same kinds of appa- ‘ratus. It is hard to find two experts who “jagree on any proposition where tubes are concerned. Tubes Withstand Rough Usage _ At my club I saw an expert install a ‘glorified set using six low-voltage tubes. One thing about it that impressed me was / the ruggedness of the tubes, which looked vexceedingly delicate, but stood up under very rough usage. _ Radio experts, when testing out a set, _ change about the tubes a good deal, like its larger cousins, but one of the prongs is fatter than the rest, so that it is impos- sible to put any of the prongs into the wrong holes and thereby connect the filament with a voltage intended for the plate only. . Soon after the new tube was made avail- able to the public, some genius put on the market an adapter that made it possible to use the low voltage tube in sockets de- signed for the older types of tubes. Now any one who owns a tube set can try out the low voltage tubes without change of wiring. Any one who has tried to light the old style tubes with dry batteries and has dis- covered that the batteries run down in a few minutes, naturally asks how long a dry cell will operate the new tubes. The new tubes, while using 1.1 volts as compared with the four to six volts required by the old, pull only 0.2 amperes as compared with 0.75 to one ampere required by the higher voltage tubes. The power consumption of the old type tube is three to five watts in the filament; in the new type it is only 0.25 watts. So an ordinary No. 6 dry cell may carrying bulky apparatus. More important still—the dry cell tube receiver will carry the joys of radio to thou- sands of persons to whom it is still an un- known mystery. Contrary to the general impression among radio men that almost every one was initiated to radio last winter, I discovered during a recent trip through small towns and country districts in six states that more than 90 per cent of the folks I met had never heard anything about radio. Most of them never had seen a radio set. Thousands to Learn of Wireless To these thousands, salesmen with port- able sets now can carry radio. In demon- strating their goods they will find an enthu- siastic welcome. Finally, think of what the portable re- ceiving set will mean in carrying cheer to shut-ins, entertainment and education to out-of-the-way places, and _ up-to-the- minute information to offices ‘and work- shops. No longer is the enjoyment of radio programs confined to those who can and this man was no exception. He tried every tube in every socket times without number. In his hurry—his audience was due in 15 minutes—the A Low Voltage Tube Set for $20 afford a storage battery. The in- troduction of the dry cell tube has halved the cost of a vacuum tube outfit. 54 Popular Science Monthly Mar recently been bitten by the radio bug and stand punishment is phenomenal in view last 90 hours or more, provided it is not had purchased a set with a dry-cell tube. of the delicacy of the filament, which is used more than one hour in 24. The life of It was all right as far as it went—broughtin eight times thinner than tissue paper and a dry cell is shortened by drawing on it for stations over a radius of two or three hun- only a hundredth of an inch wide. In __ long periods. dred miles—but he wanted a heavier vol- welding the filament to end supports and The ordinary types of B batteries are C ume of sound, so he bought a two-stage am- attaching these to the springs that absorb used with the low voltage filament tubes. plifier and a storage battery to light its shocks, the tube makers perform an oper- The plate takes the ordinary voltage—22 \, foun filaments. I listened in with An increase to 30 volts may thelr and without the amplifier, improve the results slightly. A re and so far as I could judge, The first of the low volt- abot the low-voltage tube de- age tubes was not adapted with livered just as good average for use as an amplifier, but caus results as any other I had the manufacturers have now grov cested, both when the de- produced an amplifier tube of ' tector was functioning with- that also can be lighted by the! out amplifiers and when dry batteries. It can be oth its output was fed to the used for increasing the sol amplifiers. I heard Chicago, power of a crystal detector 1 Detroit, Louisville, Schenec- set. floe tady, and other broadcast- fish ing stations without diffi- Radio on the Road nev culty and I was then in ice eastern Pennsylvania. This victory of the dry spi cell tube in making possible pre Many Users Satisfied a light, compact receiving ab! set of long range, marks an the Recently in Washington important epoch in the ex- col it was noised around the tension of radio usefulness. by government offices that the Now we can take our au navy was selling crystal de- , radio set with us where- lat tector sets of very efficient ever we go, receiving the design at a low price and : best that the air has to ca that they could be con- i offer. We can pack our ta verted into tube sets with- 5 receiving set in the bag ro out difficulty. Two or three ; >). with our collars and 0" thousand sets were sold to ; : A toothbrush. On our m government employees and Above is a ears. jgganee pera yo set, H q 1 34 hunting or fishing trips, tl other citizens, I am in- Feegnely marketed, using an ordinary diy coli (MAM or on our auto camping formed, and one reliable that makes it possible to use the low voltage ‘=, » expeditions we can tote it dealer told me that he sold tube in any tube set without changing sockets : r along with little trouble. | 25 many as 50 low voltage Orrin. Ue ant a tes com EP With a portable tube _ tubes in a day for use with the circuit before the dry cell tube is inserted. Other- receiver and an antenna these receivers. He said wise the tube may burn out plug for connecting with that no complaints had been lighting circuits, the traveler can keep in 4 received and that the users touch with the world from his hotel room. t were evidently satisfied with their per- ation that for delicacy has anything the Or, by stringing a short length of wire or I formance. watchmaker does “skun a mile.” using a coil aerial on his automobile, he can Radio experts and dealers are not unani- The low voltage tube has four prongs, make it a traveling radio station without ( tubes rolled all over the place and fell off of boxes and were subjected to varying voltages, yet they all zame through alive. Not one broke or burned out during the time they were under my observation. This ability of low voltage tubes to UR radio editor has just completed a re- markably simple and easily tuned low- voltage tube set at a total cost, including phones and aerial, of about $20. Every reader will be interested in the construction of this outfit. It is to be fully described in the April issue. To make a long story short, radio has caught up with the cartoons which, in the hectic winter of 1921-22 pictured for us the manifold pos- sibilities of this marvelous agency for carrying the human voice to listeners hundreds of miles away. Ba Dannie Bi eee i 7

Page 41

ot of or a O Fy a a “tO ONS OS March, 1923 55 Hunters with Lasso Capture Polar Bears Alive whose business has outgrown their art, except in the movies, have found a new field in the Far North, using their lassoing skill to capture live polar bears. A recent expedition employing about a hundred men skilled with the coiled rope, recently caught about a thousand full grown bears in this way. Some of the bears were killed for their meat and skins, while others were kept alive to be sold to zoos. The polar bears bask on ice floes. The hunters’ boat, a fishing schooner, was ma- neuvered in and out of the ice floes until a bear was spied. Seeing the boat ap- proaching, the bear invari- ably took to the water and the hunters found that they could effect a capture only by following him with an auxiliary high-speed power launch. When the power boat came within casting dis- tance of the bear, a skilled rope artist threw a lasso over the animal’s head, manipulating the rope so that the bear struggled to CY we of the Western ranches Captured alive, a full grown polar bear is hauled aboard ship after the animal is las- soed, as shown at right. Nearly 1000 bears were caught i in this manner during a recent polar hunting expedition release himself. The result was that the bear worked his head and shoulders through the loop and the rope could then be tightened. with- out danger of strangling the animal. As soon as the bear was securely roped, the launch towed him long- side the ship and he was drawn aboard by means of a derrick. The hunters report that the sport was equal to anything they have ever experienced, for long battles were sometimes necessary before the animal could be hoisted aboard the schooner. Automobile Body Skeleton Serves as Chassis Frame radically different in principle from the conventional design, was an in- teresting feature of a recent Paris automo- bile show. Although the question of just how a car of this general type would per- form over rough roads, is a disputed one, experts generally agreed that some of the principles employed may find wide use in the future. An important advantage of the new frameless car is its extraordinarily light weight and comparatively simple con- struction. The body of the car is the only structural member connecting the front and rear axles. Metal sheeting cut out with a die performs the double service of carrying the weight of the body and its contents as well as taking the place of the chassis frame. Metal Frame Can Be Enamelled It is this arrangement that gives the car its light weight, while the strength is as great as that of a heavy frame. A secondary advantage is that durable baked enamel finish can be applied throughout, whereas the present wooden frame prevents the use of high temperatures required in the ap- plication of this process. The suspension and air brake ar- \ “FRAMELESS” automobile chassis, Photos courtesy Automotive Industries A light sheet metal skeleton —the only structural member connecting front and rear axles—takes the place of a chassis frame in the new ‘frameless car RY THIS CYLINDER | SERVES BOTH AS SPRING AND SHOCK ABSORBER Spring suspension and brake ar- rangement of front wheel, showing cylinder mounting in which coiled springs and a piston operating against water pressure absorb shocks rangements on the front wheels are other unusual features. The front wheel is mounted to slide on a vertical guide pressing against the action of coiled springs and, through a piston, against water pressure in a vertical cylinder situated alongside the wheel. This arrangement eliminates the springs and shock absorbers now in use. Brakes are provided on all four wheels, those in front being operated by a wire cable attached to a lever, the movement of which governs the brake band. All four brakes are operated simultaneously by pressing on a single foot pedal. A Vacuum Clothes Brush 6 lire! are saying good-by to the whisk- broom in barber shops in Chicago. Attendants are using a small vacuum type dust collector, weighing no more than the electric flatiron. It is far more hygienic than the whiskbroom germ scatterer. Spice erie i ps grits Soot te

Page 42

neg ae 56

Popular Science Monthly

—

cern in Kansas City, Mo., provides a clean- erand quicker method of killing animals. The mechanism consists of a suction pump to which is at- tached a hose equip- ped on the end witha sharp blade. As used in slaughterhouses, a centrally located vac- uum pipe provides the suction for a bat- tery of blades. The animals are hoisted and suspended from a rod by chains attached to their hind legs. The “sticker” in- serts the blades in the ani- mals’ throats and the suc- tion draws the blood from their bodies in 43 seconds. Thus, the animals die in a

7 a Suction Knife to Revolutioniz Slaughterhouse Methods ESIGNED to elim- Blood is LY, eZ ae mae | inate the barbarity — al a= ' oil, bas iin. " = of slaughtering methods quick Vb! 1 | now in general practice, a suction | new butchering device, men ee manufactured by a con- wine Sang below Spe

Nae >. — sz <= = 4 eneoa In the slaughterhouse, suction for a battery of knife blades in- serted in the animals’ throats is supplied from a vacuum pipe most humane way and their blood is conserved and kept clean through- out the entire operation. In cleanliness, the in- vention will transform slaughterhouses, where butchers now wade in blood as they work. Although the present tendency in butchering is to relieve suffering as much as possi- ble, yet killing by the present methods requires from two to fixe minutes. The saving that may be effected by the new slaughtering implement may be realized when it is considered that the line of cattle, sheep, and swine killed each year in America for food and serurrs, would extend a distance of 181,0C0 miles, or about five times the distance around the world.

Three-Wheeled Auto Built of Old Parts Three - wheeled auto as assem- bled from old parts parva a few spare Ford parts of standard type and connect- ing parts made at home, J. O. Michaud, of Fort Kent, Me., has built a serviceable three-wheeled automobile. The Ford parts used were three front wheels, front wheel steering spindle, rear axle, drive shaft, pinion ring gear, and bearings. The chassis frame was of iron pipes, while the reducing coupling, the transmis- sion, and the drive shaft housing were made from available material. A nine-horsepower en- gine from an old car gave satisfaction. The entire i Se eee Ne car weighs 610 pounds. - ae

Easily Fitting Pipe Wrench Threadless and Nutless (y= of the recent additions to the pipe- fitter’s toolchest is a threadless and nutless pipe wrench, invented by Walter I. Brockover, of Tipton, Ind., which can be used on pipes of varying sizes without preliminary adjustment. The wrench consists of three parts: a handle and upper and lower movable jaws. The upper jaw and the handle each have two arms that are pivoted in such a way as to allow room for motion of the lower jaw about its pivot in the handle. In use, the wrench is hooked over the pipe and the lower jaw is raised to contact with the other side of the pipe. Bending the wrench by pressing down on the handle causes the lower jaw to move forward and the pipe is thus very firmly gripped by the teeth of the jaws. To release the pipe wrench, it is neces- sary only to raise the handle. The lower part is drawn back by this motion and the

Sea of Soapsuds Novel Window Display Lie

Shes, pa ee Y FORCING compressed air through a soap solution in an elec- tric washing machine, a furniture store has adopted a novel window dis- wnt

play scheme which has proved effec- tive in attracting the attention of passers-by. The sea of soapsuds pro- duced covers much of the display.

teeth are disengaged.

This r can bi leathe Scien! be ust ESE th le homes < toes, is scientist study 0! and sol used b bearing These home ir and kill this is e bats int ered by

. LS \ ig, : C 0) tT more auton mirro: Att diatel reflec’ Tor a maki straig N

Page 43

High w%ah is ed n= Id March, 1923 This monster South Ameri- can bat is first cousin to our leather - winged species. Scientists now say bats may be used to police our homes against insects the employment of the ordinary leather-winged bat to police our homes against flies, insects, and mosqui- toes, is now being carried on by certain scientists who have undertaken a thorough study of the subject. San Antonio, Texas, and some cities in Florida have already used bats successfully to fight malaria bearing mosquitoes. These men picture the bat making its home in a dwelling, darting here and there, and killing all invading insects. To prove this is entirely feasible, they introduced two bats into their own homes after being both- ered by mosquitoes. The result was that RR ee: emp that soon may result in Ned, ‘ Rs ue oe . \ ethyl i ped . \ , *t : ¢ \ AY the bats disposed of all of the insects in a single night. Two difficulties have arisen, however. In the first place, they have not yet found an adequate way to keep the.bats alive in captivity. They feed only while on the wing, and unless supplied with large num- bers of insects, do not get enough food when kept in a laboratory. Secondly, since the bat is little more than a winged mouse, women feel somewhat timid about having such a policeman around the house. The real importance of the research lies in the discoveries of the value of bats as de- stroyers of insects that damage crops on farms and as annihilators of mosquitoes. 57 Photo courtesy American Museum of Natural History yr Until recently the bat was one of the least known American mammals. There are 150 species, some of which have as large a wing spread as five feet Proposes Pet Bats to Drive Insects from Our Homes They are confident their studies will en- able them to devise a way to keep bats in captivity so that they may be domesti- cated to farm uses. ° The bat is a nocturnal animal, hiding in dark caves in the daytime. Some varieties migrate with the seasons, while others hi- bernate, hanging suspended from roofs of caves by their hooked claws, sleeping for periods as long as ten weeks. They never build nests. As soon as young are born—never more than two to a pair—they attach them- selves to the breast of the mother bat, remaining with her until they have gained strength enough to fly. Converted Auto Mirror Is Useful in Rowboat 7" A person rowing a boat, a knowledge of what is going on behind him is even more important than to one driving an automobile, and therefore the automobile mirror has been put to this second use. Attached to the side of the boat imme- diately in front of the rower and tilted to reflect images at the proper angle, the mir- ror affords a good view of what is ahead, making it easy to keep the boat in its straight course and avoid collisions. Nearly Two Billion Stars [ATEST estimates made by scien- tists of the Royal Observatories at Greenwich, England, are that there are approximately 1,600,000,000 stars. Of this number between 3000 and 4000 are visible to the unaided eye. The late Franklin Adams made a set of 206 photographs covering the entire sky from which it was possible to estimate the number of recorded stars at about 55,000,000. “Talking Lamps’? Warn Autoists of Danger “PTASALKING” signal lamps, with com- plete traffic regulations printed on their sides for the benefit of the passing motorist, are being widely used in some of the larger cities and at dangerous crossings. The lamps are of two types, one of which is a lamp box on a pedestal, sup- plied with red lamps that flash regularly nightandday. The other type is simi- lar, except that the lamp box rotates. Workman Studies Expert’s Actions in Movie N ORDER to instruct workmen in the best methods of manipulating a ma- chine or performing an industrial oper- ation, Major Frank B. Gilbreth, noted effi- ciency expert, has perfected a small stereo- scopic movie machine that enables the workman to study each movement of an expert in minute detail. When a man accomplishes results in a minimum of time with the least exertion, he is termed an expert. To educate other workren to become experts, this man can be used as an example. Stereoscopic mo- tion pictures are taken of the expert in ac- tion and printed upon a paper roll. To each of the separate pictures is attached a caption that calls attention to the faults or correct actions of the individual in the picture. Thus a study of an expert’s ac- tions can be made by the less experienced man by observing the film through a ste- reoscope while continually passing before the eye the successive movements that go to make up a complete operation. Each device for taking these pictures in- cludes a microchronometer, or rapid clock, that records the time on each picture, which shows paths of motion, as well as the exact time taken. =. ON ee o~ Pte a>) os ‘. ~ "v sr. 3 7 eres rs 7 St Pichon song a nT psig enc trae seh Sp ETT Rit aS “3 a >. = TN eet ee em oe eet eee Me - ste ope 8

Page 44

Popular Science Monthly March, | Why Boilers Explode —This One: Traveled 200 Feet} A Ti most spectacular recent boiler ex- Don’t neglect to test the safety valve N TE plosion—just one among the 500 that every day. | juxul annually snuff out from 700 to 800 lives ..> Don’t forget that a badly scaled boil cons' in the United States, causing property - SA is unsafe. known A loss of more than half a million ~ Don’t neglect the steam pressure companis dollars—occurred in a sawmill ~ gage or fail to have it teste and mov il ‘X three, W! i, the Arct Aa in an eff arine pressure of 80 pounds. Two years previous Arctic. to the accident, the operator had increased the pressure to 100 pounds, but later, it is T said, he adjusted the safety valve, as he thought, to blow off at 80 pounds as before. The s they W! Some Causes of Explosions I, M. U Cadillac Although the safety valve could not be ard E. found after the explosion, it is believed that Nationa it may have-been screwed up for a higher tion; — pressure rather than down. Pow , presider The price of carelessness —all that Aside from carelessness, some of the The wrecked boiler lying where it of Com remained of the sawmill chief causes of boiler explosions that could landed, 200 feet from the mill Inches, be avoided are summed up by experts in a at Le Roy, Ohio, when the shattered boiler few simple “Don’ts,” the most important occasionally—say, about once every year. was hurled high across a stream for a dis- of which are: Don’t try to raise steam in a cold boiler F tance of 200 feet from its foundation. Don’t fail to test the water gage every too quickly. The boiler was of the horizontal tubular day to make sure that the boiler contains Don’t depend on others to see that every- type, 30 years old. It was designed for a the proper amount of water. thing is all right. te e Master Gear Molds Perfect Gear Teeth in White Hot Blanks NCREASED accuracy and greater wear- die slowly meshing deeper and deeper until which the blank is mounted. The shaft I ing qualities in the production of the hot blank is a perfect mate for the die. that turns the die gear is connected by toothed gears of all types have been In twenty seconds the job is finished and _ bevel gears with an electric motor. achieved recently by the invention of a the machine is ready for another blank. The other end of this shaft has a large SBSERV revolutionary machine that forms gear The machine has four COMPAR teeth by rolling a plastic, white hot gear bevel gears, as shown in the THESE BEVEL GEARS DRIVE THE blank in mesh with a water cooled, accu- close-up view on this page. TWO SHAFTS IN UNISON rately formed master gear. Two large gears drive the Pe ' Detroi two shafts of the machine in A\ She wot wane™ f, a ‘a Gear Teeth Hot Rolled perfect unison. Inside one- Dei VY” FINISHED ) Redd of the big bevels is the die Die | ‘The Replacing the usual method of cutting gear and opposite, meshing : J the gear teeth cold from blanks in milling with it, is the finished hot cabin machines, the new hot rolling process is rolled gear. spread said to be one of the most important de- When the hot blank is two a velopments in the machine tool industry in placed in the machine,‘ it cw : Ty, yO entire a decade. Hot rolled gears already have is held securely by the ac- ‘ FB e.oWER FOR Close up of the gear roll- follow since the rolling process uses 5 ROM MOTOR: 7} FcOoLING ELECTRIC ing mechanism, showing - lakes all the material in the blank, : ee ee saree ak See Finer whereas the cutting process »)\ perfect unison, and, within, 3 necessitates cutting away a \ 4” the die and finished gear joy th large amount of the material. blank | big g2 The blank is heated white Pr vicron Cor hot in a small gas furnace at roller against which the feed for cc one end of the machine. Then cam bears, and is rotated by chairs it is mounted in the machine the large drive gear. This gear serva and a gear die is gradually hed al It FP is operated by auxiliary gearing mach brought into mesh with it as BEVEL GEARS .WHicti.! & ™ 7 —— from the motor shaft. nienc the two rotate in unison, the Meme KEEP THE TWO-SHARTS ¢ . : The motor does not run con- outfit Eas’ UNISON 6 tinuously in one direction, but |- head . instead, makes a fraction more have PNEUMATIC. OR than one revolution, then re- gram HYDRAULIC CYLINDER verses to make a little more ous § ea GEAR than a revolution in the other TI direction. The movement in ceive Ke -GMESSEONR — one direction is slightly less over Per | Bae beamed timgate arth ct a.Pecfert gear dle than in the other so that nel) itt BLANK aun t in diagram, until the leuk ts = meant two revolutions bring the same the , mate for the die teeth of the die into action. =

60 Ponular Science Moanshi..

Page 45

eet ty , Valve d boile Pressure tested Y year. | boiler every- nks » shaft ed by a large March, 1923 A 5000-Mile N THE most complete and | luxurious flying boat ever constructed, six nationally known American sportsmen, ac- companied by four newspaper and movie men and a crew of three, will fly from New York to the Arctic Circle next summer in an effort to establish an aero- marine line that will bring New York within 72 hours of the Arctic. The Sailing List The sportsmen who have said they will make the trip are I. M. Uppercu, president of the Cadillac Motor Car Co.; How- ard E. Coffin, president of the National Aeronautical Associa- tion; Harold H. Emmons, president of the Detroit Board of Commerce; Dr. James W. Inches, police commissioner of RADIO ROOM Workmen are shown above putting the finishing touches on the spa- cious flying boat in which six American businessmenesportsmen VENTILATORS © Aeromarine Airways, Inc. Businessmen-Hunters to Travel in Ship of Luxury SOLINE will travel from New York to the Arctic Circle over territory shown on the map at theright. The diagram below shows arrangement of cabins | | Te ——— JR ESS BSERVATION 7 COMPARTMENT — cuniRs CONVERTIBLE INTO BEDS Detroit; William E. Metzger, president of the Detroit Athletic Club, and Charles Redden, president of Aeromarine Airways. The flying boat, for which the hull and cabin are now complete, will have a wing spread of 104 feet, and will be driven by two 400-horsepower Liberty engines. The entire machine will weigh 7 4 tons, and will attain a maximum speed of 100 miles an hour. An Infinite Variety of Scenery The journey of 5000 miles will take from two to four weeks, since it will be made by easy stages. Leaving New York, the boat will go to Montreal, and from there will follow the Ottawa River and a chain of lakes northward through Quebec to James Bay, thence through Hudson Bay to the Arctic Circle, where the sportsmen will en- joy themselves shooting caribou and other big game. Complete equipment, an electric range for cooking, convertible beds that turn into chairs in the daytime, and an inclosed ob- servation compartment at the nose of the machine will be just a few of the conve- niences embodied in the boat. The radio outfit will have both the loudspeaker and head phones. Several broadcasting stations have arranged to give special radio pro- grams for the sportsmen, supplying continu- ous entertainment throughout the trip. The epoch-making air voyage was con- ceived by C. F. Redden who, while flying over Quebec recently, became impressed with the possibility of flying over water to the Arctic Circle. He declares that the journey involves no danger and will provide novel sport for the tired business man. 7 t1nAyn—a ELECTRIC RANGE COLLAPSIBLE TABLE STORAGE LAVATORY DAVENPORT A ROTARY soil tiller that performs simultaneously the operations of plowing, harrowing, rolling, and disk- ing, has received the approval of an English horticultural society. The motive power is supplied by a single cylinder engine, giving 4.17 horsepower at 1800 revolutions a min- ute. The power is transmitted through worm gearing to a set of eight spring Plow, Harrow and Roller Combined tines located side by side on a shaft extending across the machine. These tines, rotating at high speed, churn up the soil to a depth depending upon the setting of a shoe in the rear, which can be adjusted in five different positions. Part of the power is transmitted to a pair of wheels on either side of the machine, which serves to move the tiller forward at any desired rate. The ma- chine is kept in line by the operator, who walks in the rear of it. When it is desired to use the imple- ment as a power plant, it is necessary merely to throw out the clutches and connect the engine with the machine by belting. The entire machine weighs only 350 pounds. By turning a handle in this combi- nation power plow, harrow, disk and roller, the operator controls its movements. In diagram, note tines that rotate at high speed, churning the soi @l lean tit TE tI ie preter Neca pie ep caret ees On eS matter es ot eee SN ee TT et ee saciid oN et

Page 46

60 Popular Science M. onthly Science Opens Wonder Caves to Tourists’ Marvelous Lighting Systems, Safe Underground Paths, Automobiles and Good Roads, Combine to Exploit Nature's Age-Old Cavern Architecture N THE Shenandoah Valley of Vir- | ginia, where many of the historic battles of the Civil War were fought, science is putting the finishing touches on marvelous works of underground archi- tecture begun by nature millions of years ago, and is converting them into scenic attractions of rare beauty to entice the touring public. Electric lights, tunneled pathways, automobiles, good roads and many other

By Robert E. Martin uving® \ CAVERN AIR ROOM DRIED HERE

HEATING joi — a = CORRIDOR ~~

—_—

modern achievements are being com- ~ in some instances by the skeletons of long dead shellfish, and in other instances by the pre- cipitation of carbonate of lime—were bent and broken by pressure from below or from the sides, caused by shrinking of the earth’s crust or by local geologic action. Because rainwater contains carbon dioxid derived from the air or from decaying vegetation of the soil, it has the properties of dilute acid and is able to dissolve lime- stone, thus forming caves in the limestone formations through which it filters. The rain, of course, found entrance through cracks and crevices. It dissolved some of the limestone. Then, as the water evapor- ated, the lime was deposited again in the form of great “‘icicles,” of which those hanging from the roof are called “‘stalac- tites’”’ and those formed by drops that fall to the floor are called “stalagmites.”

e ~~ 4 STALAGMITES. ~“~sTALACTITES fierae. STREAM

How marvelous Shenandoah Valley caverns were formed. Strata of limestone, broken by the shrinking of the earth’s surfates, are attacked by rain water containing carbon dioxid, which dissolves the limestone strata, chiseling out caves above.

indicated by dark portions in diagrammatic cross section Dissolved lime 1 called ‘‘stalactites,’’ which hang from the roof, with cor- responding ‘‘stalagmites’’ on the floor of the cave into the form of great ‘‘icicles’’

iL “yi Photos © . Thro out by at time pothole quickly water ¢ them | materi: water some ¢ small into th Natur A ce age § creeks that t bed b found levels In m thoug the c to th botte mark Th and t of M popu miss Sher tour Pike has | cave prof

Page 47

March, 1923 itll: Midd ~ Photos © J. D. S:ickler Through the underground passages eaten out by the acid, water runs from the surface at times. The Shenandoah Valley is full of potholes that, lacking surface drainage, quickly empty rain water into underground water courses until cracks in the rock beneath them become filled with earth or stalactitic material. At one time a hole that had held water for many years suddenly opened as if some one had pulled out the stopper, and a small lake disappeared with a mighty roar into the bowels of the earth. Nature's Drainage System Makes Caves A cave system in limestone is really a drain- age system such as formed. by rivulets, creeks, and rivers. If a cave is dry, it means that the stream that formed it has lowered its bed by erosion and that the cave waters have found a lower level. In many caves, several levels—deserted creek beds—can be found. In most limestone caves water can be found, though hidden many feet below the level of the cave in an underground stream that flows to the sea. And, if no water is found in the bottom of a cave, there is a mud sump with marks showing where the water has run out. The newly commercialized Endless Caverns and the Shenandoah caverns, three miles south of Mount Jackson, have become tremendously popular. More than 10,000 persons paid ad- mission fees during the first 10 weeks after the Shenandoah caverns were made accessible to tourists. The perfect highway from the Valley Pike to the entrance of the Endless Caverns has drawn many more thousands, and smaller caves in the vicinity have reaped some of the profits. $250,000 Spent to Exploit Caves Improvements in the Endless Caverns, representing an investment of more than a quarter of a million dollars, include a great stone restaurant, a stone ledge over the en- trance, an adjoining farm that supplies the restaurant, an observation tower and search- light on a near-by hill, a power plant that floods the dark underground passages with radiance, and a proposed stone hotel. From the moment you follow the guide into a narrow passage that appears at first to be a blind alley, but turns out to be an entrance, you are dazzled by the glittering splendor of delicate and massive formations, a riot of exquisite coloring. (Continued on page 62) WWW. % WWMM r: WWOAAIOAAAAA ‘ dda dasamsa MMMM lll ‘ eu audi maiddididdddd Tas photograph of the spacious “Saracen’s Tent” in the Luray Caverns, gives an idea of the massive underground formations on which Nature has worked for centuries. Note size of MOI OW OME MMU EL OL LAO MMMM ALLL ULL LLL perry 61 An Underground ‘‘Ballroom’”’ HE entrance to the magnificent “‘ballroom” of the Luray Caverns is shown at left. With smooth paths, guard rails, and electric lights, caves such as this have been made as safe as hotels for tourists N > ES : SWRAAWMW WABI SEE SUSAAAAAAAAASSAAAAASAANAAN LGN add SSS wanted : , jg Be : * Paggeere WAM AAAAMAIN SSAA AAAI 4 gorgeous stalactites hanging from the dome and of the huge pillar at the left, as compared with the two men in the photo- graph. The cave’s natural beauty is enhanced by ingenious lighting net = = " ddan eect nelle Seni aE bp tie koa aexpee Poe aet PI LEE LE AI ALO at malta app ane Fae

Page 48

62 Trick Forces Tide to Lift Steamer Popular Science M onthly from Rocks ITH the aid of WV 5 Bfoct tide (8 | and an ingeni- \ ously constructed crib- bing, engineers recently succeeded in floating the steamer “Empress” from the rocks in the Bay of Fundy, after every effort to pull the vessel into deep water with tugs had failed. The Canadian Pacific steamer was on her regular run in the bay when she poked her nose high on a ledge of rock in St. John harbor in such a way that a point of the ledge be- came firmly hooked into plates on the ship’s bottom. When tugs at- tempted to pull the steamer away, they served merely to fasten the rocky hook more firmly into the ship. It was decided that the only way to float the steamer was to raise her entirely off the Steamer ‘‘Empress’’ on the rocks, showing workmen constructing cribwork that lifted her free of the ledge, ” a Pm Pa as in diagram ledge. Therefore, at low tide, a portion of the rock was blasted from beneath the bow, and there a cribbing was constructed so N that as the stern roge with the rising tide, the weight of the ship was thrown on the cribbing, Finally, at high tide, the hull was lifted clear of the ledge, and the bow rested on the crib. bing. Since the top of the crib had been thoroughly greased, it was an easy matter to pull the boat into deep water. The few plates bent by the collision were held in place by a concrete backing and the ship: was towed to drydock at Halifax. Caverns Open to Tourists (Continued from page 61) Perhaps most impressive of all sights is the Diamond Lake in the Endless Caverns. You reach a point in the caverns where you see a cleft about two feet high and about three feet from the floor. Suddenly the lights go out and the entire cavern is in darkness. “Face the end of the passage, please,” orders the guide. You comply, wondering what is coming. In a moment there is a “click,” followed by a flood of ruby- colored light that turns Diamond Lake into blood red water, reflecting countless rubies in the banks and ceiling over the tiny cres- cent shaped lake. Fantastic Forms and Colors Once again the cavern is in darkness; then soft yellow lights transform the lake cavern into a jeweled castle of yellow diamonds. Then green lights, creating an emerald lake that excites gasps from the spectators who remember Diamond Lake as one of Na- ture’s most beautiful scenic spots. There are other scenes in the Endless Caverns just as fantastic—the Palace of Fairies, where a forest of crystal formations suggests all manner of elfin, fairy, and gob- lin-like figures, enhanced by skilfully placed electric lights. There are formations of pure milky white, delicately colored stalac- tites and stalagmites of tints and shades rangeing from reddish brown (made by iron compounds) to soft gray blue (caused by the presence of manganese). There is the Hall of Giants, where tremendous stalac- tites and stalagmites lie prostrate, one of them weighing 400 tons and believed to have fallen nearly 4000 years ago. Perhaps the most awe inspiring of all is a milk white specter standing guard over what is known as ‘“‘Pluto’s Chasm,”’ a rift 40 feet deep, and 500 feet long. Dainty shawls of translucent calcite, falling in graceful folds ornamented with a narrow band of reddish brown; cascades of glisten- ing white, terraces, pools of crystal clear water, countless formations of white and colored calcite formations, combine to make the chasm one of the most beautiful pieces of underground architecture in the world. There are endless wonders in caves. To some persons the silence is ghastly; to others it is soothing. It is broken only by the dripping of water or the rolling of a pebble. Bats hang in clusters from the wall; sometimes you run across nests of wild animals, often containing bones; seeds brought in by birds or beasts send up shoots of pallid white; colorless translucent cave crickets hop about with proverbial liveliness; ghostly eyeless fishes and crabs swim about in the underground streams. In historical interest and in size Mam- moth Cave, Ky., surpasses all known cav- erns. It was made a show place as early as 1816, passing into various hands and finally to Dr. John Croghan, who bought it and 2000 acres of surrounding land for $10,000. O. Josh Wilson, oldest guide there, has shown the caves to no less than 36,000 peo- ple, receiving fees estimated at $108,000. Saltpeter miners, tuberculosis colonists, mushroom farmers, Indians, theatrical stars, singers, and even presidents, have .visited the place even thongh in the early days they were forced to go on mule- back. Other famous caverns are Wyandotte Cave in Indiana; Penn’s Cave, near Centerhall, Pa.; Washington’s Masonic Cave in northeastern West Virginia, where the first president is reputed to have held Masonic meetings; the caves of the Winds at Niagara Falls and in Colorado, and the caves of Arizona, New Mexico, and Ohio. All of these fall under the classification of exploited caves from which a_ business mounting into millions of dollars is derived. But the unexploited caves are the ones that are attracting the interest of the Cave Men’s Club of America. At every opportunity members of the club seek out little known caves, enter by ladder or rope, and explore the unknown depths, risking their lives and getting from the adventure thrills they feel are great enough to justify their trouble. Electric Iron Can Be Set at Any Temperature SING a new “even heat” electric iron, the housewife can set her iron for low, intermediate, or high heat; thus regulating the temperature to give the best results on the particular material being ironed. When a control button is set for low heat, a thermostat consisting of a laminated LAMINATED ROD eae EK POINTER SET ie AT DESIRED TEMPERATURE When heat passes desired temperature, bending metal rod breaks the circuit metal rod is so bent that any temperature above 150 degrees will cause a further bend- ing of the rod and will break the circuit until the excess heat has been consumed and the rod contracts to its original posi- tion, when thé current is again permitted to flow. When set for high heat, the thermostat acts at a temperature of 400 degrees. Any Heat of this electric iron is controlled by pressure on a button intermediate setting places a definite pres- sure on the thermostat and causes the cur- rent to be shut off at whatever temperature is demanded by the work in hand. March, W Forr Form OF F a Whe! Northw ber of recentl; stroke | ghe no record own te she iss! womat of mat An |

Page 49

A SG ( = et iron, r low, lating Its on heat, nated > TURE SET -D URE ire, ut iture end- reuit ‘med Dosi- -d to stat Any March, 1923 63 Will Women Athletes Win Men’s Crowns? Former Woman Swimming Champion Says Masculine Title Holders Must Look to Their Laurels—Girl First to Smash Record By Ethelda Bleibtrey Former Amateur Swimming Champion of the World OR the first time in history a woman athlete, in competition with a man, has broken a world’s athletic record. When Sybil Bauer, an 18-year-old girl student at Northwestern University and mem- ber of the Illinois Athletic Club, recently swam 440 yards back- stroke in six minutes, 24 4/5 seconds, she not only smashed the world’s record for that event, .held by her own teammate, Harold Krueger, but she issued a challenge in behalf of all womankind against the supremacy of man in the world of sports. An Era of Women Champions In itself, this college girl’s feat might be of only passing importance were it not for the fact that hundreds of women are crowding to the front in sports, creeping closer year by year to the championship laurels that until now have been worn exclu- sively by men in all lines of athletics. I predict that Miss Bauer’s swim- ming record definitely marks the be- ginning of an era when the world’s sport crowns will fall, one by one, before the conquests of the “‘weaker sex,” and that eventually women will wear as many of these prizes as men. I believe this so thoroughly that I am now coaching a class of super- swimmers at the Ambassador Hotel in Atlantic City directly preparatory to trials for some of these world records. The tremendous advance of women in athletics during the past twenty the front. Ethelda Bleibtrey—Former amateur woman swim- ming champion of the world and now coach of a class of women swimmers, some of whom, she predicts, will capture world’s records now held by men years, and especially in the past five years, has been a thrilling drama to me. Let us analyze some of the records in which women approach the marks set by men: The first woman in his- tory to capture a world’s athletic championship from a man — Sybil Bauer, 18-year-old col- lege girl, setting a new record for the 440-yard backstroke swim When I first began to swim, a mark of one minute and _ seventeen seconds was a splendid one for women swim- mers competing in the 100-yard event. They have gradually cut down that mark until they are approaching a time skaters. of one minute and soon they will be down to the time of 56 seconds, the record set by men. stroke marks, besides that for the 440 yards, will be among the first to fall. In golf, women are slowly but surely driving to Just how near they ‘are to the excellence of men in this vastly popular Other back- game may be ascertained from the fact that the longest drive by a man is 341 yards, the record set by Abe Mitchell, the British golfer. Yet Glenna Collett, an 18-year-old girl champion, who has not yet reached her full powers, has actually driven a golf ball 313 yards! Tennis Marvels Vie with Men In tennis, one of the first games women took up, man’s supremacy is being threatened. I am quite sure that Molla Mallory or Suzanne Lenglen could defeat all but two or three of our best men players. Made- moiselle Lenglen’s drives, according to Vincent Richards, the young ten- nis marvel who has played against her, are as hot and as difficult to handle as any man’s. Experts predict that Miss Helen Wills, 15-year-old star, will eclipse both Mrs. Mallory and Mademoiselle Lenglen. Englishwomen have become ex- perts in hockey, one of the roughest of games. Only a short time ago the Sheffield women’s soccer team from England played Philadelphia Field Club Men’s team at Philadelphia, Pa., and the latter, playing at full speed, were barely able to scrape through by a margin of one point. American girls also are proficient in hockey, and in ice racing. Miss “Gertrude Mohler attains speed very close to that of men Women are steadily gaining on men in basketball, offsetting man’s natural superior weight by their greater natural agility and team work. Even in baseball the Kansas City Bloomer Girls’ team recently played one of the best semi-professional men’s teams of New Jersey and emerged victorious. gridiron —are enjoyed College, Flying tackles, line bucks, forward passes—all the grueling plays of the by these girl football players at George Peabody ashville, Tenn. A golf champion at 18, Glenna Collett has driven a golf ball 313 ening or only 28 yards ess than the _ world’s record drive by Abe Mitchell, famous Brit- ish golfer ER eg ee eel ee es IE BG Tee Re + Tet ee _ — AS + we EE

Page 50

Popular Science Monthly Records that Show Women Athletes Are Running Close Second to Men Te oe gees eer -~ ‘ oa -~ i 7 ~ \ J >. Re oy f “Se \ ~ es aS ape es Pee So SO Se oat si ae a = \ \S / “Gayvans) Cd SN | — = ——_-— So -, | 20> mem” = | S41YARDS] PT CT Ge iy Ru =e i ; / MA ‘hoa ery x Cod aie eae ( —_ iw 4 NA, mF FS PRS \ WNL) , ; 4 / 70 We ——_—— JINR SE rats bY) yt Wey am é Me eI eee ON Tanta Aye y - by. WOW Spall APMP AC AA SSO Cn Hundred-yard dash Driving golf ball Throwing the baseball Running broad jump And women are now throw- ing themselves into a sup- posedly exclusive sport for men. The football team of ers College of Nashville, Tenn., attracted considera- ble attention last season. The first real track meet for women was held last summer in New York. Yet the marks set compare favorably with those of | young men of the same age | and development. School- | girls can now run the 100- manhood. Are You Getting the Right Kind of Exercise? he G P ce eal oe new truths about exercise in relation to your par- the George Peabody Teach- ticular job or profession—facts that you can use every day in the year to keep yourself fit—will be revealed for the first time in next month’s issue of POPULAR SCIENCE MONTHLY by a national authority on the subject, Dr. C. Ward Crampton, aide to Secretary of War Weeks in his nation-wide campaign for better American Doctor Crampton will tell you exactly what sort of exercise you need—whether you are a business executive, a clerk, a mechanic, or an outdoor worker—and why you need it. And he will give you some simple tests that will enable you to determine whether you are keeping your physical condition up to normal. Valeour Club, without pre- liminary coaching, ran a 440-yard relay, each running 110 yards in 55.3/5 seconds, a réally fast time for boys of their age. Will women ever ap- proach men in_ throwing || weights and other feats of sheer strength? One girl, || Margaret Mitchell, already has “put”? a 12-pound shot | 28 feet four inches, and is likely to shatter that mark soon. A high school boy of her age would do well to yard dash in 12 seconds or better, as compared with 10'4 seconds for boys of the same age; Miss Rhea Riedel threw a javelin 98 feet! Maude Rosenbaum threw a basketball 94 feet two inches; and Eleanor Churchill a baseball 224 feet four inches, as compared with a man’s record of Pocket ‘‘Gun’’ Shoots Tobacco into Pipe Y gnamented recent novelties for pipe smokers is a pocket “‘gun’’ hold- ing eight tobacco cartridges. The case is equipped with a plunger that forces the tobacco from the cartridge and rams it into the pipe. When not in use, the plunger rests in the groove that separates the two layers of to- bacco cartridges. A plunger forces cartridge of tobacco into the pipe 290 feet. Ellen Hayes hopped, skipped and jumped 33 feet six inches, and Maud De- vore broad jumped 16 feet 914 inches, or only four feet 10 inches less than the world record set by man. Just a few weeks ago, four girls of the heave it 35 feet. Sybil Bauer’s swimming record, of course, will spur women on to accomplish greater athletic achievements. What she did, others can do, and in a few years I believe you will see many of the marks set by men falling before sturdy women athletes. ‘“‘Feeler’” Car Records Bridge Clearance A SPECIALLY designed railway car, which not only measures accurately the clearances of bridges and of other objects along the line, but also records the curva- ture of rails and the height of one rail above the other where tracks are banked at curves, is being operated by the Pennsyl- vania Railroad. The car makes its record while traveling at four miles an hour. It has two templets, one of which has attached to it a number of hinged extensions or feelers of steel, spaced six inches on centers. In passing a bridge, the feelers strike the sides and top When ‘‘feelers’’ on this queer looking railroad car strike the sides or top of bridge or tunnel, they record clearance in feet. Another device measures curvature of rails | ee eee 7) {cee PRPR PR pp of the bridge and are deflected to the angle that permits clearance. The amount of this deflection is recorded automatically. For higher bridges a second templet is raised by a jack screw and similar readings are taken. The movement of a pendulum located in the center of the car, shows the height of one rail over another, while still another arrangement shows the curvature of the track. into and In 8 of 01 enol to ti accc 6,00 that be wou wid Popular Science Monthly :

Page 51

Fak Re WE Fee pre- na ning nds, OVS ving s of girl, ady shot d is lark y of | to irse, ater hers will ling —

‘ March, 1923 Millions of Tons i N YITH his coalbin depleted of its last shovelful, W. T. Cox, state forester of Minnesota, went out into his back yard during the past winter and dug up enough peat to keep him in fuel. In so doing he set an example for thousands of other families in his state, who ‘‘mined” enough of the long overlooked substitute to tide them over the coal shortage. In 65 of the 86 counties of Minnesota, according to Cox, there are more than 6,000,000 acres of peat lands. He says that nearly every farmer in the state could be independent of the coal dealer if he would only consume the substitute used so widely in Europe. Billions of Tons Available And Minnesota is not the only state in the Union thus neglecting its fuel resources, for the total deposits in the United States are said to contain 14,000,000,000 tons— enough to supply Europe, at its present rate of consumption of 20,000,000 tons a year, for 700 years. A large part of this peat is well adapted to power production. Peat ashes also are useful in tanning leather and in making antiseptics, cement, and fertilizer. Peat is a spongy substance, found in almost every bog or marsh. It represents one of the phases in the slow decay of vege- table matter through the ages. When plant remains fall upon drained soil, they are promptly attacked by bacteria and soon disappear. But when they fall into water, the acids formed retard the decay- ing by destroying bacteria, and a large proportion of the carbon matter in the plant material is saved. In color, peat varies from light brown to black, and in

<f of F uel Lie Unused in Peat Bogs

Why worry about a coal shortage when you can dig peat out of your yard and burn it in the furnace? Above is part of the winter fuel supply of W. T. Cox, Minnesota state forester. Blocks of peat that he spades from his yard, as shown at the right, are stacked in piles to dry for several weeks until needed for fuel consistency from that of bran mash to that of clay. Most coals were transformed from peat. Some advance has been made in the re- covery of commercial peat in other states than Minnesota. In the great Dismal Swamp, in Virginia, for example, peat de- posits covering almost 1000 square miles to a depth of from 15 to 20 feet are being mined by two large corporations that were awake to its marketable value. The harvesting of peat is still generally done with a hand spade with sides and back forming a mold. Blocks removed by this tool are placed in piles in the air,

and are turned time after time. Whé, dry, they are ready for burning. jn Europe a pressure method of drying pet in large quantities has recently been ip- vented. In its natural state peat has not the heat capacity of coal, but when pulverized toja fine flour and blown under a boiler, it is 4n excellent fuel for commercial work. The natural peat blocks, however, can be used effectively in a small furnace, stove, or fireplace.

HE feat of editing and printing 10,000 copies of the Yankton (S. Dak.) Press and Dakotan in 23 edi- tions in 23 towns in the course of a 300-mile automobile trip was recently accomplished with the aid of radio. From a radio car fitted with com- plete receiving apparatus, up-to-the- minute state news and Associated Press Print Radio Newspaper ‘On the Run” despatches sent by Yankton College wireless station, wére received. This, news, together with local news, was edited, set up, and run on a multi- graph press in a press car. Type was set while a stop was being made and the next edition was run off while the cars were on their way to the next town.

Here is the complete automobile newspaper plant. At left is radio car showing operator receiving news despatches, and at right is automobile multigraph plant

} he A Desk ‘‘Office Boy’’ : SIMPLE office desk device that does the work of office boy or secretary in informing visitors whether the business executive is absent, where he is, and when he may be expected to return, consists of a stand that supports a drum in which is a rotating cylinder. Upon this cylinder are 17 readings that cover periods of time in the ordinary business day. The de- parting executive need only turn a knob until the proper reading appears. When not used for this purpose, it forms a convenient paper holder and tray for pens and paper fasteners.

THE Editor will be glad to supply, wherever possible, names and ad~ dresses of manufacturers of devices mentioned in this issue.

March, 1923

67:

Page 52

66 bi old we * ae P. J. Madigan, in- ventor-mechanic of Chicago post office { bs * Se = a , **Keep the mail moving’’ is the central idea around which the entire equipment for han- dling parcel-post packages in the new Chicago post office is designed, as made clear in diagram the most marvelous post office in the world—a post office built for speed, where dozens of ingenious mechani- cal inventions will keep parcels on the move “every minute of the day, from the time they enter the building until they are loaded on trains for their destinations. Machines that Spell Speed More than four miles of belt conveyors that will handle 10,000 sacks of parcel post every hour; ingenious mobile hand trucks that can be loaded with mail at business houses, hauled to the post office on motor trucks, coupled into miniature freight trains and dumped with lightning speed; amazing sorting belts, chutes, and overhead carrier systems—these are just a few of the working parts that will make up one im- mense post office unit of half a million square feet capacity. Running with ma- chine-like precision, making use of every square inch of its capacity, substituting machinery for sorting and tossing by hand, Uncle Sam’s new mail clearing house in Chicago is expected to Cy tie os has practically completed SACKS DROP TO WESTBOUND TRAINS ] NEWSPAPERS, MAGAZINES, ETC.,SORTED BY HAND ON THIS FLOOR SHG 4 }/ improvement of methods of handling mails, who tinkered with old half efficient machines, stuck to his job, and finally won distinction and _ success. Nearly every inch of the Chicago post office is the product of his study and experiment, as are a score of new machines. When Madigan joined the Chicago postal service in 1894, nearly all the work was performed by hand. Cancelling machines Popular Science Monthly Postal Inventor Devises Miles of Belt Conveyors to HAE Gy SACKING TABLES TiNcoMING MAIL DUMPED ON PRIMARY FEED BELT tin pe Mabe # Ry s ‘i THESE MOTOR IRUCKS BRING FILLED DUMP-TRUCKS FROM WHOLESALE were the only machines in general use. Since Specially designed container trucks on wheels, used for mail receptacles at Chicago business houses, are picked up then, gearless cancelling by motor trucks, unloaded at the post office, hitched to- machines, improved car- ether in a train, and drawn by tractor toa feed belt, riers for pneumatic tube systems, belt conveyor facing tables, an overhead system for han- dling primary mail, and a score of other time and labor saving improvements have been added; and a large proportion of where they unload their mail without stopping them have originated in Madigan’s brain. His inventions were installed first in the Quincy Street station, Chicago, where he was in charge. There they proved so suc- cessful that they were adopted on a larger scale in the new establish a world’s speed record of more than 800 tons of parcel post a day! S And not the least of the mar- vels of this gigantic postal ma- chine is the fact that it was con- ceived and designed, almost in its entirety, in the mind of a single man, P. J. Madigan, of the Chicago postal service—a man of unusual mechanical skill, whose chosen work has been the Why Some of Your Letters Go Astray TATISTICS gathered by the Chicago post office de- partment show that last year one out of every 150 pack- ages received went astray because of incorrect address. Of 2,266,243,054 pieces of mail, statistics show that: 6,788,000 were returned to the sender; 1,021,300 were corrected and forwarded; 4,370,500 were held for postage; 97,800 bore no address of any kind; and 2,905,000 had to be disposed of as waste. This made a total of 15,182,600 pieces of mail incom- pletely or wrongly addressed or wrapped. post office. Every unit for handling par- cel post was designed to keep parcels on the move. And in accomplishing this, the simple little hand truck container already mentioned, is perhaps the most effective of all. Mounted on casters and equipped with a tilting device that permits the top of the truck to swing forward toward Popular Science Monthly PT slik) ©

Page 53

March, 1923 Keep the Mail Moving in New Chicago Post Office rn [AIRPLANE LAND ING FIELD | MAIL 1S SORTED HERE ACCORDING TO DESTINATION AND 1S THEN CARRIED BY PROPER CONVEYOR BELTS TO SACKING TABLES = ee _— > Vlas pv the operator and the bottom to open, this truck entirely eliminates the time- consuming sacking of parcels. Nearly 80 per cent of loose packages received at the post office comes from business houses. By the new system seven or eight loaded truck-containers can be picked up by one motor truck and driven to the post office. There they are rolled off the truck and eight or ten of them are coupled together, form- ing a train. A baby tractor then comes along, hooks onto the miniature train, and pulls it past a trough into which the device. Along the trough a feed belt moves in the opposite direc- tainers have been Forty men stand at the terminal of each feed belt and SACKING TABLES SEE OE packages are _ through chutes to the train level. Durinj dumped from the the process of sorting, 40 men can stand ¢ trucks by a special the terminal of each feed belt. i tion to that taken overhead conveyor system is shown by th by the train, making fact that under the old method letter it possible to unload _ posted in the early afternoon and dumpé moving containers on the facing table might be buried by | without clogging the later batch of mail dumped on top of ther conveyor or stop- before they could reach the cancelling my ping the train. As * chine. The overhead system of handlir? soon as the con-. completely eliminates such delays. emptied, they are new post office may be gained from the fag loaded back on_ that its equipment is expected to doub/ motor~ trucks and _ the speed record of the equipment install sort mail in the Chicago post office, as shown in upper returned to business by Madigan in the Quincy Street statioy photograph. Sacking at the bottom of the delivery chutes houses. By thissys- which last year handled 422 tons of paj is made easier by the racks shown in lower view tem one motor truck cel post in one day. 7 as : } 67: ‘T= time saving system of con- veying, sorting, and distrib- uting mail in the new Chicago post- office is shown in this illustration. Incoming mail is first dumped on a primary feed belt, sorted, and carried by separation conveyors to various destinaticns in the build- ing, according to the class of mail. It is then sorted according to ad- dresses and conveyed to sacking tables. From there it proceeds to chutes, dropping to outgoing trains arrives, unloads, and reloads with empty containers in just seven minutes. Once on the feed belt, the parcel travel to “separation units,” or distri bution points, on the third floor, wher they are sorted. Belts moving fror these separation units carry the parcel to their various destinations, all uncan celled mail being carried back to th first floor, where it is cancelled and de livered by another belt to the feed bel on the first floor. All separation belts on the third flooy except that which handles uncancelle; mail, deliver to spiral chutes leading t) the second floor, where parcels ay sacked and dropped through opening in the floor to ceiling belts that delivel Mail Congestion Is Prevented The saving of time effected by Madigan : + , ’ * An idea of the expected capacity of tH March, 1923

Page 54

Three-in-One Washtub—New Tying this new mop head over a kitchen broom provides a mop for floor or wall dusting, and is very useful for dusting high moldings ee This revolving washtub has three com- partments, one for hot water, one for cold, and another for starch. Each section has a stopper and waste hole through which liquids are discharged into a funnel and hose leading to sink. Especially useful in conjunction with an electric washer sert new grater Every kind of grater comes with this adjustable frame, one side of which slips out to in- Slipping rugs and upturned edges are prevented by the anti- skid catch, at the right, which buttons the rug to the floor Popular Science Monthly Household Inventions This three-by- eight-inch detach- able automatic elec- tric tank heater is equipped with a thermostatic switch that keeps temper- ature constant and saves current = Cra he, ~ i out Small and inexpensive salt and Beans are stripped of their strings by the turning of a crank on this mechanical bean stringer pepper shakers made of paper (at left) solve a lunch problem for picnickers i HROUGH the in- } vention of a process | ‘or the production of + sellulose in commercial | yuantities from reeds, ~ushes, and other weed- ‘ike water plants that ] . ) slog lakes, rivers and ' swamps, German scien- _' ists claim to have solved ) she print paper problem, providing a compara- ‘ively cheap substitute or the world’s diminish- ng supply of wood pulp. . The most common | lants used in making the cellulose from which -\oaper is manufactured ‘ire reeds, rushes, flax ‘tems, savannah grass, ‘ugar cane, jute, and ‘yamboo. It is said that most any kind of grain Cheaper Print Paper Made from Weedlike Water Plants stems can be used also.: A mower mounted on a small flat boat cuts and harvests reeds and rushes from streams for use in manufacturing print paper New crops are available at all seasons of the year in various parts of the world. The actual manufac- ture of the paper, ac- cording to reports, re- quires only two hours and is far cheaper than the wood pulp process. In fact, it is claimed that the price of the new paper will be 60 per cent less than the present price of pulpwood paper. Cardboard also is pro- duced by the new proc- ess. Indeed, despatches from Berlin say that already more than 50,000 inner soles for shoes have been manufactured from reeds and rushes. Damalam Cacemae AA anwth!.. amie.

Page 55

March, 1923 Sky Writing to Tell New Facts about Airplanes The word “Call” written across the sky above New York in smoke letters half a mile high by an ne piloted by Capt. Cyril Turner ten across the sky by an airplane in letters half a mile high recent- ly startled New York. The new method of advertising was invented and perfect- ed by Capt. Jack Savage in England. The words are written by maneuver- ing a plane carrying special smoke generators that discharge smoke pro- (Fj ten acres words of smoke writ- . =a Siz mtn OSES ean SSS ARTY ‘ =, 69, At left —How the inventor of smoke writing proposes to use his invention to study new airplane designs by photographing ribbons of smoke Captain Savage also sees in the scheme a method for studying ai) currents and the efficiency of planes. For this he proposes smoke generator: located in the forward part of a plane, The downwash, slipstream, and eddiet of air around the wings and projecting parts of a plane may be studied b photographing from another plane the ribbons of smoke enveloping the ma: chine being tested. Captain Savage is now investigating square miles for a period of from 20 minutes to an hour. Sky writing, of course, has tremendous advan- tages in advertising because of the fact that an ad that may be seen by 1,000,000 people (if made duced at the rate of 1,000,000 cubic feet a second by chemicals that react on each other without producing combustion. When written at a height of 10,000 feet, the letters are visible over an area of 100 “Burbank of Strawberries” tl $50,000 for New Variety \ , YOULD you pay $50,000 for the right to propagate a single strawberry? That is what Frank E. Beatty, presi- dent of a Three Rivers, Mich., fruit growing concern, did recently. And yet, the buyer does not consider the price he paid too great. In fact, he is willing to risk his reputation on the statement that ‘‘the plant will revolu- tionize the strawberry industry.” Beatty, an expert in strawberry culture, has been unusually successful with four varieties of the plant. He claims that the $50,000 strawberry plant, which will be known as the “Rockhill,” in honor of its originator, Conrad Rockhill— Produces more, larger, and better berries in early summer than any of the varieties now being grown. Continues its heavy fruiting during fall months until snow flies. Produces berries of firm texture, which will withstand long shipments. Surpasses all other varieties, irrespective of climatic conditions, in productiveness and quality of berries. Beatty further claims that the plants ‘oot deeply, grow luxuriant, tough leaves .ree from plant diseases, and possess sur- prising vitality that enables them to produce abundantly. For the right to prop- agate the immense straw- berry plant above, Frank Beatty, the “Burbank of Strawberries’’ (at right) paid : above New York) may be produced for $200. plan for: sky writing at night, using luminous smoke. According to thé Department of Agri culture, the straw berry is the mos valuable of all ou small fruits, coverin; three fourths of the total fruit raising ares in the United States From a commerciay standpoint, the chie value of the Beatty plant lies in the dura/ after they are picked: for the price of straw! berries on the marke} is largely governed by the fact that so many spoil while being transported to mar ket. The garden berry i; an American product! the result of a CTOs between the ‘‘pine’) strawberry of Europ) and the Amorlan wild strawberry, pr duced by Hovey “father of the Amer: can strawberry.” i bility of the berrieé, RAL A Seal PE inate fhe. == ~n eerera is Banna eomnere CGA eT een —_—__e , ea oa

Page 56

ST TS ee suction. modern municipal administration is keeping the streets of our great cities clean,” says Commissioner A. R. Taylor, of the New York Street Cleaning Department. ‘“‘The tremendous increase of pedestrian and motor traffic makes it increasingly d'fficult to keep our highways free from germ-laden dust which not only spreads disease, but destroys our clothing, build- ings, anc merchandise. In New York City 12890 (= of the most pressing problems of vacuum cleaners picked up 3,448,300 pounds of dirt and dust, cleaning an area of 54,843,152 square yards. Another machine found to be extremely efficient is produced by a Springfield, Ohio, firm. It was designed to eliminate these features objectionable in earlier motor driven sweepers: excessively wide pick-up brooms, requiring excessively wide elevator belts and perishable wooden brushes. Fine rotary disk steel brushes scrub miles of paved area is cleaned daily, 4700 cubic yards of dirt collected, and 3,000,000 gallons of water used to flush the streets.” Street Vacuum Sweepers The day of the familiar “white .wing” is passing, for hand methods no longer can cope with the mountains of dirt and dust deposited by the in- creasing horde of autos. Other cities, both abroad and in this country, are meeting the problem with cleverly designed motor driven vacuum street sweepers. These vacuum sweepers not only pick up dust and dirt from the street, spraying at the same time, but also have attach- ments for cleaning gutters, into which much of the refuse necessarily is swept. One ingenious machine, the product of a Sandusky, Ohio, firm, operates like a vacuum carpet sweeper. A huge rotary broom in front throws the dust which has been sprayed into the field of vacuum In St. Louis, within a period of 12 months, or 232 nights of sweeping, these in an upright position to the front edge of a thick plank so that their ends come just in front of three wooden harrow teeth, are the essential features of a semi-auto- Popular Science Monthly 4 Mechanical ‘White Wings” Guard City Health — Replacing the famil- car “White Wing,’’ motor driven sweep- ers like those shown below are cleaning city streets of refuse and disease breeding dust j material into a windrow so that a pick-up broom, 30 feet wide, delivers it to the elevator belt, which carries it to the dumping device in the rear. Steel brushes last longer and sweep cleaner than the wooden brushes formerly used. A spraying ma- chine keeps down dust while the machine is oper- ating and reduces disease caused by flying germs. Brushes at the side of the machine shown above sweep dirt with a ‘‘scrubbing’’ motion into a_windrow, deliver it by broom to an elevator belt and finally toa dumping hopper Operating like vacuum car- pet sweepers, the machines at right suck up dirt and blow it into trailer vans Ancient Planting Machine Used in India fy MBEE hollow bamboo poles fastened matic seeding machine invented centuries ago by the natives of India, and still used by the farmers of the South Deccan. The bamboo poles act as pipes, and at the upper end all pass through the bottom of a small wooden to the ground and are covered with earth by harrow teeth AS ' Seeds fed into a small pout drop - Ty bamboo tubes bowl that holds about a quart of grain. An abundance of cheap handmade rope _ is wound around the structure to give strength. One man drives the team of bullocks that pull the seeder over the plowed field, and a second man oper- ates the contrivance. The sower fills his loin girdle with grain, and stands up- on the plank. As the team gets under way, he puts small handfuls of grain into the bowl. The seed falls through the poles to the ground, where it is covered with earth by a harrow fastened underneath the plank. ee Nozzle for Auto Washing Fits Palm of Hand Aone the novelties in garage acces- sories is an aluminum nozzle small enough to fit in the palm of a person’s hand, and which may be used for washing automobiles. It is screwed to the end of a hose attached to a hydrant faucet and emits a fine but powerful spray for rinsing pur- poses. When used with a _ sponge, the nozzle does not send out a spray, but allows a copious supply of water to per- colate through the pores of the sponge, keeping constantly wet while it is in use. In using the washer, the nozzle is held in the right hand, with the fingers over a curved bar. Pressure on the bar turns on the water, and releasing the pressure shuts it off. If a sponge is used, it is held over the spray with the fingers of the hand holding the nozzle, while the other hand guides the hose. Pressure on grip turns on water

Page 57

March, 1923 Does Dust Shot from Sun Cause Storms on Earth? THE INITIAL VELOCITY OF AN “BOMB” 1S OF TEN EXPLODING SUFFICIENT TO HURL DUST TO THE EARTH. SCALE iN MILES PsYonekene) Terexexena) — 4 CORONA (OUTERMOST ATMOSPHERIC LAYER OF UNKNOWN GAS) NARROW QUIESCENT LAYER © Popular Science Publishing Co. tec. : By Scriven Bolton, F.R.A.S. S THE earth being bombarded contin- | ually by explosions of huge solar “bombs,” shot from the sun’s surface? Science believes that it is and that the air we breathe often becomes abnormally charged with this “bomb” dust, causing unnatural vagaries of the weather such as rain and electrical storms. These solar explosions, powerful enough to hurl electrically charged dust particles 93,000,000 miles to our earth, are 50,000 times as tremendous as the greatest ter- restrial convulsions ever known. Shot forth like great Roman candles from the sun’s fiery interior, the bombs are often 1000 miles in diameter and are composed of incandescent hydrogen estimated to have even a higher temperature than that of the sun’s surface—15,000° Fahrenheit. 50,000 Volcanoes in One Bomb Just how terrific the explosions are may be imagined from the fact that the greatest terrestrial convulsion on record—the erup- tion of the voleano Krakatoa in Sunda Strait, near the island of Java, August 27, 1883—represented but one fifty thousandth part of the energy believed to be released in a single explosion of a solar bomb. The reverberation from the Krakatoa eruption shook our entire globe, sending measurable ripples of air twice around the earth and hurling fine dust to a height of 80 miles. Yet one solar explosion hurls dust particles millions of miles into space. On the surface of the sun the force of SN QQ 5 0E>?£7=>=™Ovno€ OQgq wee 5 9 yy lt HNRNdA"L,(W~ (\ FW "01 "= '™EblF°TF7F*FVvp?BFe=’wWnn SUNS VISIBLE SURFACE ~ OR PHOTOSPHERE CHROMOSPHERE (RED HYDROGEN FLAMES) WEEE LEE, hdd hades EARTH'S BIGGEST RECORDED This diagram shows present sci- entific knowledge be -FORCE OF ® SOLAR "BOM Scace in MILES Soo 1000 j about the sun. From the _ sun’s surface exploding bombs of jncan- descent vapor, ex- erting a force 50,- 000 times as great as that of the world’s most ter- ON SAME SCALE rific volcanic erup- tion (Krakatoa, 1883) bombard us with dust clouds | aie ala at. CONVULSION (KRAKATOA VOLCANO gp, IN 1883) IS SURPASSED DAILY } SO000 TIMES BY THE EXPLOSIVE KRAKATOA I$ (voucano) AVSTRALIA gravity, irrespective of atmospheric fric- tion, is powerless to check an upward initial velocity exceeding 385 miles a second. Particles exceeding this velocity when . hurled upward by a tremendous solar up- heaval fly into space, never to return. These particles, it is believed, form the dust shoals that bombard our earth and other planets. Since the dust is electrically charged, it probably causes phenomena such as severe magnetic storms during which the compass needle is agitated. On rare occasions the surplus electric charge has been known to paralyze telegraph and tramway services. Moreover, some meteor- ologists firmly believe that clouds and rain- drops would not form in our atmosphere without the presence of this dust. It be-° comes obvious, therefore, that when the earth is passing through a dust shoal, clouds and rain may be more prevalent, and seasons subjected to bewildering vagaries. Astronomers now are seeking to discover the cause of these. strange solar bomb ex- plosions. While they know practically nothing about the heart of the sun, the, have learned that this nucleus is su, rounded by definite concentric layers, fir) by a luminous envelope of vaporous mattq called the “photosphere,”” which we s¢ when we look at the sun; then by a secor’ layer of glowing gases cooler than the ph! tosphere and forming a smoky veil from 5€ to 1000 miles thick; thirdly, by a sea of re: surging fire, consisting chiefly of flamir hydrogen vapor, and called the “chrom! sphere.” From this sea great tongues , hydrogen and calcium vapor flames a. driven outward for thousands of miles I some mighty unknown force. Finally, the outerrrost region of the sl is an atmospheric layer, consisting of uj known gas, called the “corona,” a silve) halo that we can see during an eclipse } the sun. Scientists tell us that much of the light) this halo probably is sunlight reflect’ from particles of dust like those that ty mendous solar explosions drive to q| earth in clouds. ; b Segaseiie msc ae raed pehemuethe bee eed Soe rere TY Be eine hehe, ie ace sagas ses he SOR nine tan

Page 58

72 Fog Dispelled by Oil Film on River RMED only with a city sprinkling - wagon placed- on a government barge, a mixture of oil and organic acid, and data obtained in laboratory ex- periments, Pittsburgh, Pa., scientists, co- Popular Science Monthly Surface

Spraying the water with a mixture of oil and organic acid from an old sprinkling wagon ing Department and the Weather Buraeu, prevention is possible. By pouring an oil film over the surface of the Monongahela River from Rices Landing, 35 miles south of Pittsburgh, to a point 114 miles upstream, the scientists succeeded in cutting a distinct lane through the river mists, demon- strating that any city situated on an inland body of water can rid itself of much of its fog nuisance. In Pitts- burgh, where the Mo- nongahela and Alle- gheny rivers join to form the Ohio, the fog nuisance has been so serious at times as to tie up traffic. By shut- ting off sunlight, it has menaced the city’s health and has cost thousands of dollars in jamages and in abnor- mal consumption of slectricity for lighting. The experimenters aboard the government y0at “Evelyn,” tow- ng a barge equipped vith a crude sprinkling ipparatus, began their vork at 10 o’clock one /+vening, after a heavy ‘og had settled. As the sprinkler began souring a path of oil in the wake of the yarge, a strange phenomenon occurred. “verywhere ahead of the boats was a xeavy blanket of mist; but in the rear the

operating with the United States Engineer- recently outwitted nature, proving that fog mounted on a scow (at right), ex- perimenters cleared a path through heavy fog on the Mononga- hela. Fog re- mained on each side of the oil film, as shown below

On the following morning, a trip of in- spection showed that the oil covered the en- tire surface, but was too thin in spots to be effective. Yet for the first time in five morn- ings, government men at Rices Landing could see across the river. The following facts are significant: Less than $75 worth of oil and organic acid Was consumed. Scientists estimated that if a proper amount had been available, the oil film would have been effective for about 100 days. An organic mixture

fog had been split apart, and the air was clear. This path of clear air widened rapidly as the oil film spread. The phe- nomenon continued for four hours, when the oil supply gave out. added to the oil made possible a film of one one-thousandth of an inch in thickness—the thinnest film ever created in open air. The treated oil spreads 25 times as fast as untreated oil.

| 'Speedy New Battle Tanks | for Army OLLOWING recent amazing exhibi- tions by a new amphibious gun car- riage tank that “runs like a rabbit, limbs like a squirrel, and swims like an _ tter,” nearly a hundred military authori- fies of this country pronounced it one of ) he most revolutionary war machines ever avented. Now asecond new development £ the war tank, exhibited by the army | t Washington, known as a “speedster,” ttains a speed of 40 miles an hour, and is pnsidered almost shellproof because of he pace it sets. | Tank Crosses the Hudson River »,1 The amphibious tank, carrying a “six bunder”’ and three machine guns, traveled | a speed of 30 miles an hour down River- de Drive, New York City, was then con- prted into a tractor and easily climbed a b-degree hill, finally completing its per- rmance by accomplishing the astounding t of propelling itself across the Hudson | fiver and back—1.7 miles each way—in 44 | iinutes. -|Uncle Sam owns the patents on this - Ink, which is the result of work by Walter _;aristie, former daredevil auto driver. jae tank, 15 feet long, six feet wide, and a < 57 "ee

ly A

The army’s new **speedster’’ tank, shown at left, is equipped for long distance runs and can attain a speed of 40 miles an hour. Below: The Christie amphibi- ous tank is shown starting to climb a 45-degree hill in a recent amazing exhibition in New York City, after- ward propelling it- self across’ the Hudson like a boat

© {nternational weighing six tons, has four wheels on each side that run on a track laid down by the endless tread. When operating with the endless tread removed, the machine attains a speed of from 30 to 40 miles an hour. In the water, the tank is driven by detachable propeller blades. The new speedster tank is equipped for long runs, carries a 75-millimeter field gun, can accommodate 10 men and supplies and ammunition sufficient to last 10 days.

Popular Science Monthly

Page 59

March, 1923 Sugar Syrup Prevents Frozen Radiators O PREVENT automobile radiators from freezing, glucose—or sugar syrup—has been recommended by Dr. Charles H. La Wall, of the Philadelphia College of Pharmacy and Science, as a substitute for anti-freezing compounds containing denatured or wood alcohol. Because glucose does not evaporate, Doctor Wall declares it is far superior to other mixtures. Using about a pint and a half of ordinary confectioners’ glucose to a gallon of water, he finds that the mixture starts to become slushy at a temperature of about 10 degrees above zero, but that it does not actually freeze and harden even at six degrees below zero. The mixture does not corrode metal parts, he says, nor does it affect rubber. Ladder of Steel Tubing Is Light and Durable Gree tubing is being used by a Detroit con- cern in the manu- facture of ladders, which, itis claimed, are lighter and stronger than wooden ladders. Oval tubing of specially tempered steel used for the side members is drilled to take round tubular rungs. Threaded tie bolts through the centers of the rungs hold the ladder together. How rung is joined to side members Flexible Plow Is Unit with Tractor Y AN ingenious method of at- tachment, a new type of tractor plow recently introduced into the United States by Harry Ferguson, of Bel- fast, Ireland, be- comes a unit with the machine that hauls it. Only slight exertion on the part + eed Photo courtesy of Farm Mechanics Forming a unit with the tractor, the plow may be raised or loweréd as shown at left. If the plow strikes an obstruction, as above, the rear of the tractor is Yaised automat- ically so that the wheels spin and the plow is not roken Seen ne colton ge arp ‘ar Ree TR of the operator is required to raise the bot- toms of the plow from the ground. When raised, the plow is suspended in the air, so that the tractor may be driven over rough country, backed up, or maneuvered in any desired way. One of the unusual features is that the tractor power is conveyed to the plowshares through an inverted V-shaped arrangement of steel bars. Should the plow strike a rock or any other obstruction, the pull tends to straighten out this V and the bearing is so shifted that the rear of the tractor is raised from the ground. This allows the tractor A NOVEL rowboat rudder that may be used either for steering or for propulsion has a rudder board cut in the form of a U. When the rudder is This Rudder Steers or Biocels Rowboat Operated by a lever, as above, the swing- ing flap of this rudder like a fish’s tail to to be used for steering only, this open- ing is closed with an oval flap hinged to the arms of the U. When this flap is swung free, it trails in the wake of the rudder. If the rudder is to be used for scull- ing, one end of the crossbar of the rudder post is con- nected by an iron , rod with a lever - that is moved for- : ward and back- ward like a pump handle. This causes the rudder with its swinging flap to oscillate horizontally _ like the tail of a fish, and imparts to the boat a forward mo- tion of fair speed, not as great, how- ever, as that im- parted to it by the more strenuous use of a pair of vigor- ously pulled oars. shown oscillates propel the boat March, 1923 wheels to spin and thereby prevents th plow from breaking. The depth to which the plows penetrat is regulated by a single wheel attached o one side and the tilt of the shares is adjuste by a handle. The entire plow mechanisr may be raised by depressing a lever. Sings as She Writes Three Words at Once | Y WRITING three words at one tim and accompanying this feat with a son a young German woman, Thea Alba, re cently exhibited her remarkable ability t conduct simultaneously four separate nor related actions. j Many of us who have tried to write figure eight on the wall while describing ‘ circle with one foot will appreciate the ski required for such performance. It was he ability to execute this exercise that mad her aware of her unusual powers. Phys; _ cians who became interested in her e! hibitions decided to study her actions t determine whether her feats were acco plished by separate yet simultaneov thoughts or by an unusual ability to tran fer her thoughts quickly. If these questions are answered, Germa| psychologists believe they will be able t tell us more definitely about our menté, processes, | weir me han Ain Spe erie cote etre: aa eS aaron mane tC = Sarg ee ies TT a ee aa 2 ARETE I

Page 60

74 by scientists, Ben H. Peterson, recently gradu- ated student in chemistry at Coe College, Cedar Rapids, Ia., has succeeded in explaining some of the reasons why many stucco homes crack and otherwise deteriorate sooner than they should. His discoveries ‘may serve as a foundation for other experiments that should prove valuable to builders of stucco homes in the future. Peterson, who did this work preliminary to writing his thesis for graduation, had no references to guide him. He constructed his own testing apparatus, and worked out his own formulae. Two of the devices he used—a machine for measuring the cross-breaking strength of a par of stucco and a delicate device that measures ex- pansion under various degrees of heat and cold to the millionth of an inch—are so ingenious that he has been B' DELVING into a field hitherto little explored Popular Science Monthly Young Scientist Explains Why Stucco Houses Crack These two houses show the wrong and the right way of stucco con- advised to have them patented. more than 2000 analyses. He During his experiments, the student tested more than 6000 stucco bars of varying compositions and ran ) tested tensile or “stretching” » strength, the cross-breaking 3trength (by which he deter- ' mined capacity to bear weight), expansion, solubil- ty, and a number of other » yualities of the building ma- / terial. Variation in stucco material, he found, is due chiefly to lime content. The Effects of Rain One of Peterson’s chief _ vests proved how much weight ' 2 bar of stucco loses by ex- ) cosure to water. He found chat about five per cent of the ) weight of a stucco bar was ' ost after the bar was im- ‘ mersed in water for 120 ‘/nours. From this he com- ' outed how long a_ stucco * ouilding could withstand dis- + solving by rain and snow. _. In general, Peterson’s tests "tended to show that the ' cracking of stucco on a house 7. ss due not to composition, that the stresses on wide ex- panses of the material are not _ broperly taken into consider- » ation when the house is built. Sa on es sap eres EN PETERSON, the young stu- dent whose experi- ) within certain limits of lime ments have revealed ‘rontent, but to shrinkage important new facts ‘ Huring setting and to the fact about stucco con- struction, is shown above working on the apparatus (de- scribed in diagram) with which he tested the cross- breaking strength of a bar of stucco. )) He found, however, that an pxtremely high lime content Resting the bar on supported rollers, he applied a weight box, connected with a sand box, to the middle of the bar. A stopcock shut off the flow of sand at the *auses abnormal shrinkage. / His practical recommend- ation to architects is that they should panel strips of stucco more than six eet wide, thus relieving the strain caused by varying temperatures, weight, and solubility forain. Paneling also will facilitate repair, breaking point of the bar he says. Unbroken strips of stucco all the way across a 30 or 40 foot house, he found, are subjected to fearful strains, even in ordinary ranges of temperature, and are apt to crack. _ How Stucco Compares cereale it is impossible to give positive comparisons as to the relative cost and durability of brick, frame, and stucco houses, architects gen- erally estimate that on a basis of 20 cents a cubic foot for frame houses, brick houses of the same class cost 22 cents, and stucco approximately 21 cents a cubic foot. In durability, brick con- a. struction is rated first; stucco second, Re *t and frame third. py As to the relative advantages of each, with Frame and Brick the frame buildings are attractive, easiest to build, and lowest in first cost, but are greatly exposed to fire risks and require much upkeep. Stucco homes are considered extremely attractive, are warm in winter and cool in summer, and their first cost, as well as upkeep cost, is low. Brick homes cost most, but, as with the stucco house, again the cost of up- keep is extremely low, though they lack somewhat the variety possible with stucco houses of the same price. '%6 struction, judged by the results of Ben Peterson’s experiments. In the house at the left, wide, unbroken expanses of stucco result in cracking, while in the house at the right such expanses are prevented by the broken architectural design Small Powered Bench Saw for the Metal Shop pomagl of production in a shop or fac- tory in which metal rods or pipes must be cut to size in large quantities is being increased by the use of a new and extremely handy power driven bench saw that weighs, with motor, only 40 pounds. The new saw, driven by one-eighth- horsepower motor, is one-thirty-second of an inch thick and has a diameter of 314 inches. Due to the thinness of the blade, there is little waste of stock in cutting. The work-holding device has the form of pliers with V-shaped jaws, like a pipe vise, and is pivoted to an arm of the saw sup- port. It holds the stock to be sawed at right angles to the plane of the saw. By lifting the handles of the holder, the operator holds the stock against the teeth of the saw. A stop gage is provided for adjusting the length of the part to be cut off from the stock. The efficiency of this saw may be judged from some test results. It cut through a one-half-inch round, cold-rolled steel rod in 40 seconds. Through five-eighths-inch brass rod 250 cuts; through three-sixteenth- inch brass rod 1800 cuts; and through five- eighth-inch round hard rubber 1200 cuts were made in one hour. The new bench saw, showing plier- like device for holding the work Burbank’s Own Life Story ALIFORNIA this month celebrates the fiftieth anniversary of Luther Bur- bank’s wizardry in creating new flowers, fruits and vegetables. This grand old man of plant breeding is one of America’s most picturesque and fascinating figures. All his past achievements are dwarfed by the fact that at the age of 74 he has come to cherish the dream of raising a better race of humans according to laws he has discovered in plant raising. Burbank writes of his work and his dream in an article that every American should read in the April number. Popular Science Month} ~~ ct Of bh = ™m _- ~~ .« oe ott at Go 2 6a sf

Page 61

March, 1923 Tesodectooying Moss Used to Stull Mattresses the South, especially Louis- iana, derives an income of $3,000,000 annualiy has been developed by the commercializa- tion of methods of converting the picturesque but tree-destroying “Spanish moss” into a cheap sub- stitute for horsehair for use in mattresses and upholstery. Spanish moss is the name given by Spanish settlers to an epiphyte or “‘air plant,” gray in color, which hangs from the tree branches in the South, looking like enormous beards. Although like an ordi- nary parasite in that it grows over the tree, it does not derive its nutrition from the tree, but from the air. The best Spanish moss grows to a length of four or five feet. Most of it is gathered after cypress trees are felled for the saw- mills. In the bayou dis- tricts, moss gatherers float under trees in flat boats and drag the air plants down ' with long poles. Then they carry the moss in bundles to _ their homes, where they heap it in big piles, sprinkling these with water, which causes the outer bark to rot off. After it has been thus cured, the moss is sent to a ginnery, where it is run through aé_ set of double rollers equipped with teeth, a fan blower, and a baler. The rollers crush the sticks, teeth comb out the moss, while blowers dry the moss and blow away the trash. Each year Louisiana ships from 2000 to 5000 carloads of ginned moss, which brings from six to 11 cents a pound. \": INDUSTRY from which Mechanical Arms Pick Up and Elevate Boxes in Tiers RRANGEMENT of boxes Louisiana. iene, Spanish moss “cnet like gray beards from an avenue of oak trees in Left, gatherer returning with his day’s ‘‘catch’’ of moss gtd paRSp atte se 2 ie igre iene yo eee pth eee thes Moss gin, where ‘“‘vegetable hair’’ is combed, freed ee Tn and rie Machine stuffing mattresses with ginned Spanish moss used as horse- and other materials in tiers has proved such an expense to factories that engineers, casting about for a means of doing this work mechanically, have suc- ceeded in designing a small elec- tric storage battery tiering truck equipped with sets of arms that imitate human arms. The attachment consists of two sets of arms and an elevating mechanism, located on the front of an electric truck. In using the longer set of arms to pick up square boxes, it is necessary to have the material raised a few inches above the floor. The operator lowers the two arms and inserts them under the pile by moving the truck forward. Power is applied to the elevator screws and the load is raised from the floor. The truck is then run to the tier and the material raised to any elevation up to six feet, and deposited. Mechanical arms grasping cylindrical container March. 1923 hair substitute The second set of arms picl up round or flat packages b holding on to handles. Whe changing from one set of arms t the other, the operator simp] moves a lever and the two se automatically change position This is done by gear qua rants connecting the two set Fertilizer from Stray PROCESS for the artifici: production of effective fe tilizer from straw has _ bee patented in England. Straw is subjected to th action of a culture of cellulos; destroying organisms with tf addition of certain chemicals { start the reaction. The fin product contains about two pe cent of nitrogen. Any farmer, is claimed, can turn his enti: straw crop into about half i weight of nitrogen-bearing fe tilizer. ,

Page 62

4 ; 76 Re-Covering Your MOTORIST, who had painted his road- ster dark blue and had given it a high luster with coach varnish, found that the old mo- hair top looked shabbier than ever by contrast. He decided to re-cover the top himself and found the work not as diffi- cult as he had imagined. He measured _ illlll! the amount of ma- terial required and bought sufficient heavy, closely woven brown duck for the new top, as well as binding tape of the same color, some brown cambric for the shabby bolsters, an oval rear light glass with an aluminum frame, round head uphol- stery tacks, and a little oak coach var- nish. As he removed the top with a tack puller and pliers, he noted how each piece was fastened. He then refinished the top bows with varnish, cut new stay straps from brown duck, and made them fast to the bows. The bolstering was covered with cambric and fastened in place. Using the old top as a pattern, he REAR CURTAIN HAS GLASS LIGHT 1N ALUMINUM FRAME N SS i)" sett i ANN SE NTL GET MN FETT A Scat cea a an he Ye x By G. A. Luers BROWN SILK THREAD The old top serves as a pattern for cutting a new cover Auto Top Cheaply next cut the brown duck to the exact shape and sewed the pieces together on the sewing ma- chine with heavy brown silk. The rear light was set in the back section =-->----=2=5pY and then the new cover was spread over and tacked to the frame while the frame was held in position with bindings of heavy twine. The fin- ishing tape was put on and the top then matched in newness the ap- pearance of the newly painted and varnished car itself. No special tools are required and nothing about the work is difficult, although care must be taken to cut the materials the exact pattern of the parts removed and in alining the top bows properly before putting on the new covering. It is necessary to use a tape line frequently to make sure that pieces on opposite sides are uniform and that the rear curtain is located so that the light is in a central position. A new top usually increases a car’s selling value far more than the cost of labor and materials involved. SHAPING BOLSTERS COVERED WITH BROWN CAMBRIC NEW BOW STAY STRAP. HEAVY BROWN DUCK COVERING Popular Science Monthly Rotary Brush Removes Carbon Dust from Auto Engine Eee the tops of pistons and the walls of the combustion chamber in an auto- mobile motor are not thoroughly cleaned of fine carbon dust after they have apparently been scraped clean. The removal of this dust can be ac- complished with a wire brush and a small hand drill. Cut off the brush handle, drill a hole exactly in the cen- ter, thread in a wood screw, and cut off the head of the screw. This provides a metal shank that can be held in the hand drill chuck. With this rotary brush the tops of the pistons and the walls of the combustion chamber can be polished, which insures better engine performance and tends to prevent the carbon forming quickly again.—R. FRANKLIN MUNDORFF, Kansas City, Mo. Wooden Blocks for Garage Floor A NEIGHBOR who recently put in ¢ portable garage and was particularly anxious to have it comfortable, made a floor of wooden paving blocks obtained at ~ a nominal cost from the surplus stock of a street paving company. The earth was leveled and the blocks laid in even rows. Since the blocks were creosoted, no precautions were necessary to prevent decay. In case it - becomes necessary to move the garage, the floor can be taken up and relaid.—L. D. W. 4 3urned Out Electric Lamp Tests ». Automobile Spark Plugs : bile mechanic to test out spark plugs » vhile the automobile engine is running re- ) yuires nothing more than a burned out if electric light bulb ; and a piece of wire. Nn The wire istwisted around the socket to form an exten- sion andis touched against the engine head while the cen- tral terminal of f the lamp is pressed ) .gainst the spark plug binding post. If the ) ‘park is functioning properly, it is visible getween the lead-in wires in the globe. Removing Small Fender Dents : , quanted every autoist is confronted at ; some time or other with the task of re- oving a small dent or dents from the nder of hisautomobile. This issometimes difficult under- king, but a eae | mple method N 5 DENT 5 IN = FENDER Wihat usually |) vorks well is to ‘lean the dent )’ jarefully, fill it vith solder, and » icrape off the sol- er flush with the i urface of the fender. The solder is then »; jainted to match the rest of the finish. : | Such a repair is apt to be more satis- ‘‘iactory in appearance than when straight- | ined with a block and hammer.—F. A. L. 4 i ‘TSE addition of a vibrating coil will sometimes remedy serious difficul- ties in an ordinary battery ignition system. Such a system supplies a single spark and when the ignition, carburization, cy)- inders, and valves are in first class condition, that is sufficient. When, how- ever, the ignition coil breaks down, the ignition mechan- ism and the carburetor be- Vibrating Coil Overcomes Bad Ignition points are closed. Sometimes retiming may be found necessary. This expedient is particularly effec- tive in improving the running of a faulty engine at low speed because the series of sparks occur when the engine is operating on practically a closed throttle. The coil is mounted so that the bottom contact is grounded on the frame of come worn’ or are out of adjustment, and the cylin- ders, valves or valve stem leak, a succession of sparks is apt to improve the run- ning to a marked degree. | lower contact to the top of | the distributor. The coil An ordinary vibrating coil, such as is used jin Fords, is substituted for the regular coil. There-' fore, when the breaker points close, a steady stream of sparks passes between the spark plug points. The breaker mech- anism is designed to generate a spark at the plug points when the breaker points ‘open, but this device starts a stream of sparks when the breaker points close, previous to opening, and ‘this stream continues as long as the “GENERATOR 7 CONTACTS ON COIL FORD IGNITION COIL WITH VIBRATOR How the vibrating coil is connected the car or the engine and a wire is carried from the wire of the circuit breaker connects with the upper con- tact, and the other wiring from circuit breaker to switch and to battery re- mains unchanged. Since a vibrating coil costs little, it is possible to try out this device without much expense. Installations that have been used have given such satisfactory results that it may be concluded that a used car fitted with a vibrating coil is given a new life not possible even by entirely renewing its single spark type of ignition system.—A. L. B. Repairing a Cracked Windshield O REPAIR a cracked windshield, first take a piece of sheet steel and bend it to the shape of a channel slightly larger than the thickness of the glass. Next, soak a piece of canvas or similar goods in shellac and lay this over the edge of the glass. Force the channel over the canvas onto the glass.—J. S. MITTAG, JR. sid th thi

Page 63

March, 1923 Tools for the Home Workshop and Their Care The Kit I Use for Odd Jobs about the House By A. E. Elling to do all the odd jobs about the house that would cost money if you appealed to an out- Have you enough tools? Have you Do you know how to care for I YOUR home workshop really well equipped side man? the right tools? them properly? Good tools represent a permanent and valuable investment, which can be wasted by lack of care. Too many tool users buy them in a rather haphazard fashion, get- ting odd tools for odd jobs, one at a time, without building up a well balanced, com- pletely planned set. As a result, they find that the needed tool is not at hand in an emergency. I have listed below what seems to me the ideal tool set for general house woodworking jobs. If my own tools were lost, these are the ones I should feel it necessary to ob- tain. Others would be needed for bench work and still others for metal work; I am speaking now only of general household woodwork. The list is, of course, not com- plete, and yet may be too complete for Crosscut saw, 26 in., 8 pts. Ripsaw, 26 in., 5 pts. Compass saw, 12 in. Backsaw, 10 in. Hacksaw frame, 8 in., with blades. Fore plane, iron with wood bottom. Jack plane, iron or iron with wood bottom. Smooth plane, iron. Block plane, iron. Rabbet plane, iron or wood, % in. or Lin. Chisels—%4, 34, 74, and 1 in. Butt chisel(short) 14% in. Gouge, % in. Cold chisel, 5% in. Auger bits—%, %, 5%, 3%, and % in. Expan- sive bit with 2 cutters. Gimlet bits or bitstock twist drills, from 1/16 to % in. Screwdriver bit, 34 in. Rose count- ersink. Brace, 8-in. sweep Hammer with bell or slightly rounded face Screwdriver Two-foot rule Marking gage Trysquare, 6in. Oilstone Oilcan Combinatign pliers, 6 in. Carpenter’s pincers, 8 in, Monkey wrench, 10 in. Level, light metal or wood Spokeshave, wood or metal, 2 or 2% in. cutter Cabinet scraper and bur- * nisher Sliding T bevel Half round wood rasp, 10in.; flat bastard file, 8in. Saw vise, saw set, and slim taper saw files, 5, 6, and 7 in, Tool grinder’ Steel square, 16 by 24 in. Wing dividers or car- penter’s scriber Nail set, 1/16 in. cupped point CUTTER AND CORRECTLY INCORRECTLY CUTTER CAP GROUND * _ SHARPENED MUST FIT CUTTER £ CUTTER PERFECTLY HERE eect : Seeks A B Cc D 4 F Al SMOOTH PLANE SINGLE TOOTH PLANE FOR PREPARING SURFACES FOR VENEER (SCRAPING CUT) BLOCK AND BULLNOSE PLANE alg tome =o Ht LOW ANGLE PLANE LOW ANGLE BLOCK PLANE (SHAVING CUT) Fig. 1—Points of interest about plane cutters and two extreme types of pl Three Experts Unlock Their Toolchests for You LIVING in what might be called a toolmade world, every man finds fascination in the subject of tools and tool craft. In fact, the use of tools in the home workshop has lately become a leading hobby in this country—a hobby that is winning new recruits daily. “What tools shall I buy?” and “How can I get the most out of my tools>”” are two questions repeatedly asked us both by these new tool users and many others who already have the home workshop hobby. Tocompress authoritative answers to these questions in the smallest possible space, POPULAR SCIENCE MONTHLY asked three experts to tell just what tools they use in their own home work- shops and how they care for them. Mr. A. E. Elling tells of woodworking tools on this page, Mr. Joe V. Romig discusses the tools he uses for home metal work on page 112 and Mr. George A. Luers writes on ‘How | Choose Tools for Repairing My Auto,” | on page 113. some; but it will give you an idea of what experienced tool users find essential. In buying small bits I prefer to get bit- stock twist drills that will cut both metal and wood. As ‘to the care of tools, most common tools are comparatively foolproof if given a reasonable amount of attention. The plane is one of the tricky tools, but when the home worker once learns how to keep his planes, chisels, and saws in good condi- tion, he will not have much trouble. Tools should, of course, be of good qual- ity to start with. I remember a young man learning his trade who was trying out a smooth plane he had just bought. Having no success with it, he appealed to me and I sharpened it and told him to try again, but Rnbecepeeer Serer cee in a short time it refused to cut. Then I knew the cause was not in the sharpening or setting of the blade, but in the poorly tempered steel. After taking off a few shavings, it fell down on its job. This is the greatest discouragement that is apt to come to the amateur woodworker —trying to keep in condition a piece of soft steel or, much more rarely, a very hard or brittle blade. Some mechanics profess to be able to judge by looking at it, from its color and general appearance, but person- ally I have never felt sure of this and I notice that these men, like myself, want the maker’s name back of the blade as a guarantee that it isa piece of good steel. If, after sharpening a tool, you find it will not hold its edge a reasonable time on tough wood, exchange it, have it tempered again, or throw it away. When not properly adjusted, planes sometimes choke or chatter and are not sweet cutting. A careful examination must then be made in both iron and wood planes to see if the back or cap iron fits perfectly tight and snug when screwed to the cutting iron, as at A, Fig. 1. Sometimes a very slight opening in one corner will let in a light shaving and that at once chokes the plane. Use ah oilstone and a fine file on the back iron to make the two blades fit abso- lutely tight, so that not the thinnest shav- ing can get between them. Again, when the iron is in place, held by a clamp in iron planes, or in a wedge in wooden ones, the blade is sometimes tighter on one side than the other. This may be only a trifle, yet enough to cause trouble. It may be remedied by adjusting the seat or bed of the plane with a file or chisel. It is absolutely necessary that the blade should (Continued on page 110) tipo gn NIRS TRS 5A fo SEAT SAw CLAMP AND FILING GUIDE — > MWA © NAKKMAAN © ANAWAAWW 8 ANNAW Fig. 2—Saw vises and diagrams to aid you in | sharpening your saws

Page 64

HE addition of drawers for ‘3 by 5” filing cards and a rack for sta- tionery makes this telephone table a particularly useful piece of furniture, and it can be used, when necessary, as a writing table. The telephone rests on a swinging arm and turns back out of the way when not in use. A compartment with a door that lifts is provided for telephone directories. The stool is kept under the table except when needed, and slides on two runners, so that there will be no danger of scraping the floor or racking the stool in handling it. Both the table and stool are of the simplest construction. They can be made of oak, gum- wood, or mahogany, or of one of the cheaper woods, such as birch or whitewood, and stained ch tides sae senlinetiscenl or enameled to match other pieces of furniture in the room in which they are to be used. aD a Ma ae ee ae: Some Dimensions The table top is 17 by 21 in. and stands 30 in. high. The telephone ' arm has a round spindle | that passes through the top and the first shelf = U u and serves asa pivot. A , stationery rack is pro- |. vided at the back, to the PS IAG ROR PS LIST RG IPS TO. warty : [ | jp 1 i { ek 14 Full size details and complete bill of materials for this attractive telephone table and stool are contained in Home Workshop Blueprint No. 18 A EW pieces of furniture Fk that the home worker of can make are more ap- || preciated or will better repay '? his efforts than a cedar chest. TS a a It is comparatively easy to build a chest, the material costs | comparatively little, and if | care is taken in selecting a good +) design and working out the SECTION THROUGH A-A details accurately, the home mechanic is pretty sure to Popular Science Monthly’ Telephone Table Serves as Writing Desk wi) left of the telephone arm, thus giving the table its right to pose as a desk. Directly beneath the top is the directory compartment, which should be no larger than necessary to hold the telephone books. For very thick directories, such as the New York City directory, the depth of the com- partment should be increased accordingly. This space is closed by a door hinged at the top, with a knob for lifting it. Filing Cabinet Is Included Below the directory compartment are three drawers, two of them for holding 3 by 5in. cards. These cards can be used for names and addresses, memoranda, and indexes that it is desired to keep handy. The drawers are each 12 in. long inside, so they will hold a large number of cards. The center drawer is narrow and may be used for pens, pencils, ink, and other writing materials. The stool stands 17 in. high and has atop 16in. square, in which two holes are cut to provide a hand grip. If oak is used, and there is no need for matching, try a more unusual finish, such as frost oak or forest green. The full working details of the tele- phone table and stool and a complete bill of materials are contained on a 15 by 22 in. blueprint (No. 18) that can be obtained for 25c from the Blue- print Service Department, POPULAR SCIENCE MONTHLY, 225 West 39th Street, New York. How to Build a Cedar Chest that Will Last for Generations framed with flush panels for the sake of durability and to avoid cracking, is 19 in. by 3 ft. 4 in. ¥% by 134 in. cedar, mitered at the corners. The base is The feet are mahogany. The mahogany frames are made almost entirely of 44 or 3 in. by 114 in. strips. lower strip, however, is 2 in. wide. The Each frame is glued up separately, chamfered as shown, and cleaned off. The corners are then mitered and the frames are glued to the cedar box and held in place while the glue is set- /i-make a finer chest than the )} average commercial one. A good chest improves with ); age and often becomes a fam- ily heirloom. The rich color- ing of Tennessee cedar is never }) tiresome and deepens with age. -4 And the usefulness of a cedar 7} chest goes without saying, as 4 it forms an ideal storage place '+ for furs, linens, and valuable * } fabrics, serving as .a hold-all. ; One of the most strikingly beautiful chests craftsman can make is the ma- hogany trimmed ' a ° ee ee oe ima is a red cedar », ¥ box, with simply made joints, to which are |, applied frames of thin mahogany. These '.} form a panel effect and the contrast be- » | tween the two beautiful woods enhances _'} the grain and coloring of each of them so ) that the result is exceptionally fine: | % The chest proper is 3 ft. 2 in. long, 17 in. | "wide and 19 in. high. The top, which is that the home- SECTION ON BS FRONT Mahogany trimmed cedar chest, the parts in cedar being indicated by the half tone shading. Blueprint No. 17 gives additional details A commercial chest in walnut and cedar 3-4" i :{9" = . Cette 6" “aales® deat gr —ait@ ting with hand screws and, if pie be A i A |? fp eo necessary, a few brads. A 1, 0) ST i simple mahogany molding is Pit : x ) J mitered around thechest above ; the base. ory The escutcheon for a chest ‘s of this character should be a a handmade, if possible. The GROOVE,GLUED CROSSWISE 1 design for the one shown on moet oo) the chest is based on a four- Ned leaf clover motive. The han- dles are shaped from maple fastened to the ends with countersunk bolts. Strips of brass or copper ry are then screwed (OA over -the handle > ends as illus- |jf = =, trated. Lae a =z: A sliding tray, “5533 = ; 6 in. less in SS length than the inside length of the chest and 414 in. deep inside, is provided, and for durability the joints should be dovetailed. Two or three ordinary chest hinges may be used with the offset flaps sunk suf- ficiently into the cedar to allow for the additional thickness of the mahogany trim. For a finer construction, continuous nickel- (Continued on page 100) Y Seat chest of standard design Marc

Page 65

Lael all _- -ae: March, 1923 The \RWIN Line of AUGER BIT SETS THE IRWIN BIT SETS are the newest thing in fine tools. The new Borcase and Borkit illustrated are both exclusive features of the Irwin line. Both the case and the kit of bits are made so that all the bits can be kept in the order of their sizes. This means quick selection of the exact size needed. In the new Irwin Borcase and Borkit all bits are pro- tected from rust—and as they don’t come in contact with other tools they keep their keen cutting edges. THE BORCASE is made of matched hardwood, tongued and grooved; glued, pressed and nailed. A positive lock keeps out the = dust. Handsomely finished with two coats of water-proof shellac. THE BORKIT is made of eight ounce slate colored duck, bound with braid. To prevent rust and dust the kit is lined with non-tarnishable green flannel. A strong web strap and heavily Irwin Borcase nickeled buckle keeps the kit snugly closed when not in use. For the Home. Craftsman Readers of the Popular Science Monthly’s Home Workshop pages will find Irwin Auger Bits in the handsome new box or kit just what ‘they need for doing fine work. A bit for every purpose will help you turn out clean, workmanlike jobs. Irwin Bits come in sets of six, ten and thirteen bits. Carpenters and cabinetmakers use more Irwin Bits than any other bits made. For good work use the same bits used by profes- sional tool users. Do you know the names of the three major parts of a bit?—what the opening connecting the cutting edge The New Irwin Borkit with the twist is called?—what a solid center bit is? You will find these and Dealers: Your customers will want the scores of other questions answered in Irwin Bit Sets in the handsome new boxes our book. and kits. Attention arresting window and Every man who loves tools will want counter displays can be built around the new a copy of the interesting and useful Irwin Borcase and Borkit. If you are stocking book ‘‘How to Select, Use and Care them, play them up strong. If you haven’t for Bits.’? We will be glad to send seen the new Irwin Sets write us to-day for you free a copy of this illustrated book. full information. THE IRWIN AUGER BIT CO. WILMINGTON, OHIO. Originators of the solid center principle and sole manufacturers of the genuine Irwin line of bits and Augers. the IRWIN Bit peepee Req. U.S. Pat Olsites

Page 66

cae aos ies & i} ia. | fi 2) . 3 ay ; aS. i 1 ey } 4 / ' i Aeon NSIT RAE Pe 80 Popular Science Monthly “The Man of a Thousand Tools” By Lorry Jacobs OES your daily work grow dull some- times? Do you feel misplaced in the thing that you are doing? Would you like to find a healthful hobby that would bring you both recreation and ad- ditional income? Then listen to this story of ‘‘The Man of a Thousand Tools,’”’ who spent 29 of his working years working at jobs that failed to interest him or bring him the joy of accomplishment. Clement Hopkins of New York did this—and then suddenly found the thing to which he had unknow- ingly been suited all his life—woodcarving. And he mastered it completely in the short time of three years. For 29 years, the man now known as The Man of a Thousand Tools” worked variously as an actor, a stage manager, and at the clerical work to which he was forced to retire when his health forbade his traveling. And he felt, more and more, that he must get relief from the sedentary work that occupied eight hours of every day. But he kept on, not realizing what was the matter with him, until a serious illness forced phy- sicians to tell him that he must find an activity to occupy his spare hours— some sort of a hobby in which he could really feel an interest. Began with a Few Chisels Hopkins cast about vaguely. Then fingers communicated to his mind the fact that they wanted to be working with something. He immediately set out for the nearest tool store and the nearest five-, ten-, and fifteen-cent store. There he bought half a dozen carving tools and a cheap wooden frame. There are some men who take natu- rally to toosl. Hopkins always had an aptitude for doing things of a mechan- ical nature, but he did not regard this oer as anything unusual. So, with his carving tools, but no great enthusi- asm, he set to work to try and embellish the simple frame he had bought. In a short time the home- ly piece of wood had taken on a graceful design that surprised his friends and Hop- kins even more! That was the start. Then followed a thorough study of the history of woodcarving; evenings spent in examining illustrations of the beautiful designs wrought in wood of other days; weeks spent in experimenting with the use of new tools he began to accumu- late; and then, a real effort to emulate in beauty some of the more simple masterpieces he had been studying. All that was three years ago. At that time, Hopkins could not tell a framing chisel from a fishtail gouge. Today he has a brilliant and remunerative future ahead of him as a wood- carver, knows the use of every woodcarving tool, and has an interest in life that has re- carving is revealed ‘“FTNHE greatest thing my work has given me,”’ says Clement Hop- kins, expert woodcarver, “is the realization that there are probably thou- sands of boys who have no chance to allow their fingers to show their skill. “‘My greatest dream is the establishment of a free school - workshop, where I can teach such boys a marvelous way of making a living”’ The man of a thousand tools at work, and, above, a corner of one of his toolrooms stored his health and given him a joy in living. His equipment of tools runs into the thousands, ranging from chisels and gouges that will give an incision of the fineness of a hair, to huge tools with a 2-in. sweep. He has sets upon sets of straight chisels and bent, fluters, parting tools, long and (ea The remarkable beauty and character of Mr. Hopkins’ Italian walnut chest and, above, two triptychs in this reproduction of an antique short bent gouges, a hundred hammers, saws, mallets, planes, and a lathe for turning out round pieces to fit some intricate de- sign. His tools fill three rooms and he has 38 toolchests. To see Hopkins working in his little studio perched on the top floor of a typical. dark-halled tenement in the out- skirts of Greenwich Village, Manhattan, you would think that he had spent his life working in his chosen profession. He has accomplished what seems to be a miracle in three short years. Using all his spare time, Hopkins carved scores of frames, never two alike, and then turned his attention to triptychs, thcse shrinelike altar pieces of ecclesiastical de- sign, with two doors that open and dis- close the contents. To copy some of the medieval designs more perfectly, Hopkins even learned the art of gilding. And for these he found a ready market that helped pay for the tools he had col- lected. Carving a $1000 Chest The harder he worked, the greater grew his ambition. Wondering what commer- cial value his work had, he took several pieces to a Fifth Avenue art dealer. The man was amazed that Hopkins had mas- tered the difficult art in so short a time without training. There, Hopkins noticed a fifteenth-century carved walnut chest. Making inquiry, he found that complete photographs of the chest were in a book in the Public Library. He secured a photo- graph and after several months of te- dious labor, completed an exact rep- lica, making each part in cheaper wood first, to be sure of himself. For the ornate hinges, side irons, and a big lock and key made of hand- forged iron work, he engaged the aid of artisans, who dupli- cated it to a nicety. Finished, the chest sold for nearly a thousand dollars. Hopkins had another chest of white wood, also a re- plica, but that was for his own home. Orders for triptychs and frames kept pouring in, some even coming from Europe. Finally came an order for a pulpit, which will far surpass anything Hopkins has_ ever attempted, with its symbolic and ecclesiastical figures to be done in high relief and _ its Gothic lettering. This com- pleted, he will go on making furniture. Yet he is the man who three years ago did not know what to do because his work did not give him the joy of living that makes life worth while! Smal furni attrac You, them no pa ing p phon Furni of yo harm in fi easily scrat invol All y bru. WO Joh eas}

Page 67

ne en eS / I ee ee, A Ya WIG! Tne - — March, 1923 The Proper Finish Will Make Your Furniture Small odd pieces of modern furniture add greatly to the attractiveness of every home. You, yourself, can easily make them for your family. There is no particular trick to construct- ing porch swings, tables, tele- phone sets, etc. Furniture, woodwork and floors of your home can be made to harmonize if a little taste is used in finishing them. You can easily refinish dingy, shabby, scratched wood. Our method involves practically no expense. All you need is a little time—a brush—and JOHNSON’S WOOD DYE. Harmonize and quickly, without a lap or a streak. It penetrates deeply, bringing out the beauty of the grain without raising it—dries in 4 hours and does not rub off or smudge. JOHNSON’S WOOD DYE Johnson’s Wood Dye is made in fourteen beautiful shades, all of which may be easily lightened or darkened—full directions on every label. In Wood Finishes you get just what you pay for. If you buy cheap brands you may be sure they are manufactured from cheap raw materials, cheap labor and the completed job will be a disappointment and the finish will not stand up. The Johnson Line of Artistic Wood Finishes is complete—it includes Johnson’s Wood Dye— _ Paste Wood Filler—Enamel and Undercoat—Permacote Wall Finish—Floor and Sani-Spar Varnish—Prepared Wax—-and Johnson’s Wood Dye is very everything necessary for your easy to apply—it goes on easily furniture, floors and trim. 81 = Mir XS L/] UZ —— If you are building or remodeling you should have our book on refinishing. The finish of your floors and interior trim is a matter of great importance, for a beautiful piece of hard wood may be absolutely ruined with the improper finish, whereas an ordinary piece of wood is a pleasure to the eye if well finished. a FREE-This Book on Home Beautifying This Book tells how to finish wood in artistic stained and enameled effects. Gives practical suggestions on mak- ing your home artistic, cheery and inviting. Tells just what materials to use and how to apply them. Includes color card—gives covering Capacities, etc. Use coupon below, a “The : PROPER TREATMEN WORK oRS. WOOD ane 8 FURNITURE PSS Oe ee Saree a a a an a 3 S. C. JOHNSON & SON, Dept. PS3, a RACINE, WIS. (Canadian Factory—Brantford) B Please send me free and postpaid your Instruction & t Book on Home Beautifying and Wood Finishing. @ The best dealer in paints here is.................. : DE PRES 6 60s de dbinlcvbe Stas déiae st aeldee P| oe... Se ee eee 3 le ge N° 9. sa a rent eee eater we he 2 Ea we ee Ee a ee

Page 68

SibE EE ABT ED. ars Os Werte te w & ee Pe ret a I et I Nt

BE AR LEN REBT BEML T LEI Sp SEI We OA ERAGE ANY ROLE ME TRI TATE EN MESES DS Ag. 13 i. i Ay hy ai nO try ig .Y }

82

Popular Science M onthly

Better Shop Methods 4 How Expert Mechanics Save Time and Labor

Broaching Lowers Costs in Many Machine Shop Jobs ROACHING is often the quickest B and most satisfactory way of finish- ing the interior surfaces of oddly shaped holes, and sometimes the only one. Square, rectangular, and splined holes, used in automobile construction, are in- variably made by the broaching process. While machine broaching pays only when done on a production basis, nevertheless, small broaches, such as are pushed through the job under a power or arbor press, are becoming more popular and more used every day. No modern toolmaker’s kit is complete if it does not contain a set of a few assorted square and rectangular broaches. Tool slots in boring bars and tool holders and square and rectangular holes in jigs and tool fixtures can be cut with small broaches that the average mechanic can easily make himself. A useful set of small broaches for the toolmaker is shown in the accompany- ing illustration. A good grade of carbon steel must be used for the broaches; a car- bon content .90 to 1.10 is about right. Designing and Making Broaches In designing a broach, several things must be noted, such as the kind of metal to be worked, the thickness of the work and the amount of metal to be removed by the cutting teeth. Thin pieces require a broach with closely spaced teeth. The amount of metal removed decides the chip room and the metal to be cut determines the lip and clearance angles of the teeth. The parts of a broach’s anatomy are the pilot, which must be turned to a few thou- sandths of an inch smaller than the hole into which it is to enter; the body, which is tapered to allow each successive tooth to do its share of the cut, and the sizing por- tion, which usually contains about six teeth, all the same in size, their function being to finish the surface of the hole accu- rately to size. The head is made a few thousandths smaller than the sizing teeth and acts as a guide member in keeping the sizing teeth in perfect line while passing out through the hole. Whenever possible, broaches should be made with spiral teeth, as this type takes a shearing cut, eliminates chattering and digging in, and, as the spiral effect staggers the teeth on opposite sides, the broach works better in thin pieces. After the broach blank has been shaped up to the proper size, it is centered on the lathe, the feed screw is geared to the de- sired pitch, and a tool, as shown, is used to cut the spiral on the corners of the broach, leaving a land at least 1/16 in. wide. It is then an easy matter to set up the blank broach in the vise on the shaper and cut the teeth to the proper angle by throwing the vise over to the angle of the marked spiral. After the teeth have all been roughed out, the broach must be annealed to pre- vent the trouble caused by warping, which often spoils an otherwise good broach. The annealing takes out the internal strains of 84 By Joe V. Romig the metal and softens it for the final finish- ing of the teeth, which is usually done with a fine file. Care must be exercised in ob- taining the proper clearance angle of the cutting edge, which varies from 3 to 5 degrees. Blue paint is smeared on the land section before filing, so that it can easily be seen when the exact cutting edge has been reached. The proper hardening and drawing of the temper determines the durability of the broach. A hard broach will break and a

pio — TAPER TEETH appa eany CUMIN}

CTT] SPIRAL TEETH

RAKE PITCH K<y Y on S°T05° im CUTTING EDGE FiuLeT? 1K 0.08 eatin oi LOE 3 6 i4qnRE) “ores Sow ” 5% 3° BOD TOOLMAKERS SET

SECTION THROUGH A-A INLAID BROACH BAR

; T TRESS ANGLE A BUILT uP - OF TOOTH

SET AT LIP ANGLE RADIUS OF FILLET LATHE AND CUTTING SPIRAL ON LATHE SHAPER TOOL

Method of marking out spiral broaches on the lathe, various types of broaches, and a small job upon which broaching saved money soft one will wear out quickly. An oil or gas furnace should be used in hardening so that the piece can be heated evenly to the proper temperature recommended by the steel company that supplies the steel. To heat a broach in an open coal fire invites ruin be- cause of scaling and burning. If no other fire is available but a coal fire, protect the broach from the flames by first laying in several pieces of wood, and let them char thoroughly. Care Needed in Tempering In the quenching, too, much care is neces- sary. If the broach is cooled unevenly, it will warp. Upon withdrawing it from the furnace or fire, immerse it vertically in a tub of water and stir it around in small spirals, increasing in size until the piece has cooled. Test with a file for hardness and then shine up the lands of the teeth with emery cloth prior to drawing the temper. Temper can be drawn on small broaches in sand heated over a bursen burner, or ip the open flame of a bunsen burner. By drawing and quenching several times the most uniform results will be cbtained. Ip each individual drawing, allow the heati to take place slowly, so that the heat wil] penetrate to the.interior of the body. For general use a broach made cf good carbon steel should be drawn to a medium straw color, or a little darker. Broaches should not be used to shape and size rough cored holes, as the sand and scale will ruin the teeth at one pessage. Rough or cored holes are first prepared by drifting them out with a solid drift, leaving just sufficient metal in the hole for the final sizing. Lard oil is an ideal lubricant for use in broaching; it finishes well and cuts freely. An example of successful broaching is illustrated to show the practicability of broaching for saving labor and money when the quantity of work is sufficiently large to warrant the expense of making the broacheg, An automobile maker sublet a ccntract for the machining of several thousend trake levers to a small machine concern, with whom the writer was at that time ecnnected in the capacity of machine superintendent. The designer of this part of the truck called on his print for a cored hole filed out to fit the squared ends of the brake shafts. When the lot of castings arrived, we found that the cores had evidently shrunk, as the holes were all about 1/32 in. too small. Last Piece “Mikes” like the First We decided at once to broach, and started that same day to drift out the scale and sand, while working on the broach it- self. Broaching was done on a smal] power press, and one broach machined the whole lot of steel castings, the last hole looking and “miking”’ just the same es the first. It is this exactness and perfection of ma- chining duplicate work that makes broach- ing such a well liked and paying proposi- tion. Broaching appeals to the manufac- turer as a means of doing high class work quickly and cheaply with urskilled labor. Some private sets of broaches I have seen included, besides the regular complement of square and rectangular shapes, round ones as well, and also small keyway broaches for cutting the keyways in small gears from 14 in. up to and including 1 in. in diameter. For the model builder and home workshop mechanic, a set of square and rectangular broaches will make for better and more accurate work.

Shims Make Erasing Shields ERY thin shim stock, such as is used for liners for connecting-rod bearings, will make good erasing shields. Holes can be cut in it with a knife to permit the cor- recting of small details that could not be erased without damaging surrounding parts, even with the ordinary commercial shield.— JOHN KILIAN.

Popular Science Monthly

———__ i in lat te

March, "a

Page 69

March, 1923 | 83 ot ememesenet nicer ie and Now — 2 stores atone eee ee STAINLESS STEEL by — BROWN & SHARPE > RUST-PROOF—will not stain or discolor, but will always retain its bright finish— clean cut graduations in 8ths, 16ths, 32nds and 64ths, of the characteristic Brown & Sharpe accuracy. Get one from your dealer today Ask for No. 350—You'll like it BROWN & SHARPE MFG. Co. © | A Six Inch Rule (Pocket Size) of Providence, R. I., U.S. A. March, 1923 85

Page 70

Popular Scvence Monthly

a cma TR LER TORE TE TNT ETE LE TED PRT RGR To NCEE orn " URN IT, FET IS ‘ : ; Wo hee SS. a ee) nal oo gg RNR NI RAMI PRE NS Pe eel a i A ed Ls SA pa AINE Bi SABES GP Pe = + irer ot

- % TAPER) ‘| ee CORNERS FiuleD “Ut nN -L* 4 WITH WAX 4 RAO. \ La fistarer | he ! aes . te 77 Ie TAPER 7 t ' U LF —— The simple pattern before and after provid- ing the draft. The dimensions shown in- clude the necessary shrinkage allowance

been taken care of in the drawing. The pat- tern is shown both befdre and after the draft is put on. The heads of the nails are set below the surface of the wood and the pattern is sand- papered and given one coat of shellac. After this is dry, the pattern is again sand- papered. The nail holes and the corners are filled with wax and two more coats of shellac are applied, care being taken to allow each coat to dry thoroughly and to sandpaper the pattern after each coat. The pattern is then ready for the foundry. It is best to have the cast made in gray iron. (Continued on page 86)

ee eee

Page 71

lonthly | March, 1923 a ” ‘Le Ic] © | for + cially le iron -k well mak. 1e for rn is ade a igs in they 1 has 1 it is sions eces- have U PER id- in- pat- the the nd- lac. nd- 1ers 3 of to | to he t is WJ “Making thing Why, the job is half done when a fellow starts with tools as fine as these Sargent Planes. And it’s easier to do the careful, finished work you can be proud of. See these planes at a ‘dealer’s to-day. Buy them and realize tool perfection! Auto-Set Bench Plane with the new chromium steel cutter that keep an edge. So rigid it will not chatter on hard wood and knotty or other difficult surfaces, even when cutting across the grain. It may be ad- justed quickly for coarse or fine cuts. The clamp, when replaced after removal, will always return to its original position. A fine, capable, all- round plane for your workshop. Steel Pocket Plane and Steel Block Plane are lizht and indestructible. They are particularly handy for fitting corners, etc., and for the delicate fin- ishing touches to your craftsmanship. SARGENT & COMPANY 50 Water Street New Haven, Conn. He is using the Sargent Auto-Set Bench Plane in fitting a drawer. This plane willcome into use more frequently than any other in your equipment. It is so sturdy it willdo heavy work without complaining, but so handy it can be used on the finer jobs, too, SARGENT PLANES Is pure del ight! Sargent Pocket Plane Sargent Steel Block Plane Sargent Auto-Set Bench Plane SARGE | | Jools & Hardware

Page 72

— URGE PLY ERE LTE TS ARTI TS eacmaien se pod fas ay Ning dM Ce ea RT 7 ORE ARNETTE Five New Ways To whiter, cleaner, safer teeth—all late discoveries Dental science has been seeking ways to better tooth protection. All old methods proved inadequate. Tooth troubles were constantly in- creasing. Very few escaped them. Beautiful teeth were seen less often than now. Dental research found the causes, then evolved five new ways to correct them. The chief enemy The chief tooth enemy was found to be film—that viscous film you feel. It clings to teeth, enters crevices and stays. Food stains, etc., discolor it. Then it forms dingy coats. Tartar is based on film. Most teeth are thus clouded more or less. Film also holds food substance which ferments and forms acids. It holds the acids in contact with the teeth to cause decay. Germs breed by millions in it. They, with tartar, are the chief cause of pyorrhea. Much left intact Old ways of brushing left much of that film intact, to cloud the teeth and night and day threaten serious damage. Two ways were found to fight that film. One acts to curdle film, one to remove it, and without any harmful Bepsadent REG.U.S. The New-Day Dentifrice A scientific film combatant, which whitens, cleans and protects the teeth without the use of harmful grit. Now advised by leading dentists the world over. 88 scouring. Able authorities proved those methods effective. They were embodied in a tooth paste called Pepsodent, and dentists the world over began to urge its use. Other essentials Other effects were found necessary, and ways were discovered to bring them. All are now embodied in Pep- sodent. Pepsodent stimulates the salivary flow —Nature’s great tooth-protector. It multiplies the alkalinity’ of the saliva. That is there to neutr&lize mouth acids, the cause of tooth decay. It multiplies the starch digestant in the saliva. That is there to digest starch deposits on teeth which may otherwise ferment and form acids. It polishes the teeth so film less easily adheres. Prettier teeth came to millions One result is prettier teeth. You see them everywhere—teeth you envy, maybe. But that is only a sign of cleaner, safer teeth. Film-coats, acids and deposits are effectively combated. Send the coupon for a 10-Day Tube. Note how clean the teeth feel after using. Mark the absence of the viscous film. See how teeth whiten as the film- coats disappear. Cut out the coupon now. Popular Science Monthiy 10-Day Tube Free '* THE PEPSODENT COMPANY, Dept. 726, 1104 S. Wabash Ave., Chicago, IIl. Mail 10-day tube of Pepsodent to ‘Only one tube to a family. BETTER SHOP METHODS Machinist Can Make Angle Iron (Continued from page 84) The casting should be milled on the in. side and worked off on the outside in g shaper and laid aside for a week or more to LN “So fff ° c) =p igHOLe SMALL GROOVE —T-SLOT BOLT; ft S34 i * 9) ee ot Be & 8 rs File ~ oe: LI Le HOLES ee age Shoe f Susstio 2 STRAPS STRAP WASHE Details of the straps and bolts used with the angle iron season. It should finally be ground all over, except, of course, the inside. If the gray iron is close grained, it will hardly be possible to tell the piece from steel when finished. The small V may seem superfluous to some mechanics, but for any of the finer grades of work, such as gage or tool making, _it will prove invaluable, as when it is needed, it is needed badly. The V on the top edge is for holding bosses and the like. Some machinists may consider the di- mensions I have given too light for average | work, although they are those I have used _ for my own angle iron. It is, of course, a simple matter to make the pattern a little heavier; both legs, for instance, can be 1 in. thick, the bracket % in., and the finished dimensions in proportion. Large Wrenches from Discarded Ford Radius Rods UGGED and substantial wrenches for tightening or loosening the nuts hold- ing spring clips and automobile wheels may be made in a repair shop—where many of them are required—out of bent and broken front radius rods from Ford ears. An 18-in. section of the radius rod, with the eye at the end, is cut off and the end is TWO STURDY SOCKET WRENCHES MADE FROM ONE FORD RADIUS ROD hescseccaa HEAT END OF ROD RED HOT AND Q PLUNGE IN BRINE ¢———— — AFTER SHAPING CASTELLATED NUT Sx WITH TOP DOWN nee HARDY HOLE \N ANVIL Powerful tools for heavy work are quickly forged from old auto parts heated red. The castellated head of a nut is started in the eye after the red hot end of the rod has been placed over the hardy hole in the anvil, and the whole nut is driven through. While still hot the end is plunged into brine. The whole process of converting a radius rod into a wrench of this type takes less than ten minutes, and the resulting too] stands up under the hardest usage.—F.A.Y, Popular Science Monthly a March, 1§ M

Page 73

nthly ———__ ———., Iron ie in. in a re to | all the y be rhen 3 to iner ing, the ike. di- rage ised e,a ttle el the ed for Id- lay of cen ith March, 1923 l is —_— EON et OP CoNFIDENCE in your tools is the first step toward a good job—whatever you’re attempting to make or repair. That Nicholson Files are known and used by thousands of mechanics and skilled artisans in every civilized country, is proof positive: that they have earned the con- fidence of men who know good tools. Nicholson Files are scientifically tem- pered to hold their cutting edge under hard service. They feel right in the hand, cut right from the start, and save time and labor at the work bench. When you tell your dealer you MUST have a NICHOLSON, you’ll get the file you want. { 1—Use a NICHOLSON 6” Flat File for Radio construction. 2-Use a NICHOLSON 6” Square File for sharpening your tools. Creative Work demands eee et 4 —Keep a NICHOLSON Round File handy to enlarge holes in metal or wood. 3—NICHOLSON Files are useful in repairing a typewriter. 5—A NICHOLSON 6” Hand Dead Smooth File to sharpen knives and shears. 6—A NICHOLSON Warding File makes a balky key turn the lock. F—A NICHOLSON Tungsten Point File is handy to have about when a gasoline engine shows ignition troubles. thly March, 1923 NICHOLSON FILE Co. PROVIDENCE ,R.1.,U.S.A. 87 89

Page 74

ee ad Re ei ad mee AE NOE DA MPI YEE IO II TT CR INES ow aes ‘ | Be § * y Ky 5 ib, iia t x if; tek \ F Hi § See ee at ree 88 He smokes a meerschaum pipe fifty years old Packed with Edgeworth he thinks no other pipe can compare with it We have run on the case of three generations of pipe smokers preferring | the meerschaum pipe to all other pipes. Not only that, but all three generations smoked the same meer- schaum pipe (in turn, may we be allowed to add). For further details we refer directly to the present owner of the ancient pipe. “Dear Sirs,” he wrote us, “I have a meerschaum pipe originally purchased and smoked by my grandfather. When he died, he willed it to my father, who smoked it continually throughout his lifetime. “When the pipe came to me, I was a little dubious about accept- ing the family respon- sibility of keeping up the tradition. I tried several brands of tobacco in the pipe and they all made me sick. Then some- one suggested Edgeworth. “From that day to this I have smoked no other tobacco—no other pipe. “Give me the old family meerschaum and a little blue can of Edgeworth and I can get all the enjoyment out of smoking there is any time of day or night. “Perhaps I’m prejudiced, but that’s the way I feel about pipe smoking. And that’s the way I intend to feel as long as you continue to make Edgeworth.” Well, we can reassure our correspondent on that point, for we intend to go on mak- ing Edgeworth just as long as there are smokers who would give up smoking if they couldn’t get Edgeworth. And we intend to go on making friends for Edgeworth by sending out more free samples. So if you haven’t tried Edgeworth, send us your name and address and we will im- mediately forward to you generous helpings of both Edgeworth Plug Slice and Ready- Rubbed. For the free samples, address Larus & Brother Company, 59 South 21st Street, Richmond, Va. If you will also include the name and address of your tobacco dealer, it will make it easier for you to get Edge- worth regularly if you should like it. To Retail Tobacco Merchants: If your jobber cannot supply you with Edgeworth, Larus & Brother Company will gladly send you prepaid by parcel post a one- or two- - dozen carton of any size of Edgeworth Plug . Slice or Ready-Rubbed for the same price ~ you would pay the jobber. BETTER SHOP METHODS Chassis Frame Converted into Strong Shop Truck SLIGHTLY bent and otherwise useless auto chassis will serve for the frame of a shop truck. Use solid steel shafting for the axles and clamp them to the under side of the frame, as shown. Handles may be provided at the rear so that the truck can be pushed back and forth. It is in- tended mainly for use along alleys and bins, where the track does not turn to the right or left. Planks 2 in. thick are fastened to the frame to serve as a bottom for the truck. AUTO FRAME CAN BE COVERED WITH BOARDS = PIPE SHAFT © —CAST IRON WHEELS——: A truck for heavy work that will stand unlimited abuse This is done by drilling holes in the channel iron and riveting on the boards. The wheels can be provided with solid rubber tires if the noise of the cast iron wheels is undesirable.—DALE R. VAN HORN. Running Solder in Strips ie THE small shop, where expenses must be kept down, it is customary to buy solder in its cheapest form—the pound bar. There are many jobs, however, that could be executed more easily if the solder were in the form of long, narrow strips similar to the higher priced commercial wire solder. To make such strips it is merely nécessary to use a simple cast iron ladle with several small holes drilled through the _ bottom, close to one of the sides. The ladle is tilted back a trifle and half filled with molten -solder in such a way that the solder will not run out. It is then carried over a smooth iron plate and turned so that the solder runs out of the holes and forms long, narrow strips, as shown. These harden immediately upon striking the cold iron and can be removed as Shopmade wire solder | soon as they are poured.—C. M. WILCOX. ‘Marking Holes to Be Bored A MACHINE shop making up some plates that had to be drilled with a large number of holes, but that could not be conveniently handled in a drill jig, used the special marking punch illustrated. The tool was turned from cold rolled steel and the V marking edge was made tosis! meena the diameter.of STEEL TEMPERED the holes that °N 5X? CENTER CUTTING EDGE) | wereto be drilled. Special punch for drilling | The center ex- tends beyond this edge and serves for locat- ing the punch accurately. The tool was | tempered, so that the circumference of the holes to be drilled could be marked dis- tinctly after their centers had been fixed with a prickpunch.—L. S. R. * Popular Science Monthly Clearness of Tone sensitiveness 1n receiving signals over a wide range, comfort, and adjustabil- ity are the distinguishing characteristics of the Stromberg-Carlson Radio Headset Made by a firm which has devoted 8 years to the man- ufacture of radio apparatus, backed by 28 years’ experi- ence in the manufacture of high grade telephone equip- ment. The forked cord construction permits the separation of the receivers so that two observers may “‘listen in” simultaneously. Order Stromberg-Carlson appa- ratus through your electrical merchandise dealer or write for free bulletin No.11029-P. S. describ- ing exclusive Stromberg-Carlson features. STROMBERG-CARLSON TELEPHONE MFG. CO. ROCHESTER, N. Y. March , ( :

Page 75

March, 1923 ATKINS SAWS | SILVER _| STEEL The Symbol of Saw Value eel he ng re, | | il- Atkins No. 10 ‘Easy ? g Grip’’ Hack Saw Frame. 4 Adjustable from 8 to 12 inch blades Get Theas saw for every use, tells how and facts on building work. cut saws, # =. metal-cutting job. us to-day. ee ddd a ddd Y y SWAB AS and tables. dollars to a SMOMOOosss SSS Sss purpose an SA SSSA Non-Breakable Hack Saw Blades Cut Faster, Easier and Do Not Break Put an Atkins Non-Breakable Blade in your hack saw frame, and REE , Books on Saws “Saw Sense’’ shows you the best to test and file saws and gives helpful tables **Care of Saws’’ explains in detail the use and care of hand saws and cross- J *“*Hack Saw Chart’’ shows the cor- | rect hack saw blade to use for each To get these free books, write your name, address and dealer’s name on the margin of this page and mail it to ‘‘Saws in the Shop’’ - ® Sent Free This book is full of helpful shop hints, Worth ny saw user. It shows the right saw for every d con- tains suggestions that will save you time, energy and money. Write = us for your copy, NOW. you'll feel the difference at once. It will saw the toughest metal much faster and easier than ordinary blades, hold its cutting edge longer, and will not break. There’s a reason. These blades are made of selected steel, and are hardened and tempered by an exclusive gas-and-oil process, which gives a hard, keen cutting edge and a tough, flexible body to the blade. You can eliminate losses of time and money due to breakage of brittle blades, by using Atkins Non-Break- able Hack Saw Blades. Prove it for yourself. Send ten cents and tell us what metal you want to cut, and we'll send you a sample 8 or 10 inch blade that will out-cut and out-last any other blade. “A Perfect Saw for Every Purpose” No matter what kind of a saw you require—hack saw, hand saw, back saw, compass saw, keyhole saw, cross-cut saw, circular saw, buck saw, meat saw, pruning saw, portable drag saw machine, or in _ fact, any saw for any wood or metal cutting purpose—Atkins offers you a saw that will do the work quicker, better and easier. Atkins Hand Saw The famous ‘Silver Steel’? used exclusively in Atkins Saws, is the highest grade saw steel made. It takes a keener edge, cuts faster, runs easier, stays sharp longer and needs less filing to keep it in shape, than any other saw. The name Atkins on a saw stands for the utmost in saw value. It has won that enviable reputation because at the bench, in the machine shop or wherever Atkins Saws have been used, they have proved to be the best money can buy. E. C. ATKINS & CO., Inc. | Dept. D-20 INDIANAPOLIS, IND. Makers of ‘Silver Steel’? Saws and Tools sold by Lead- ing Hardware Dealers and Jobbers. Mill Supply Houses and Factory Branches all over the world

Page 76

Ragen ERO REE NG aaa NA Fe rT en ne ea CTE SORT ne) bi ait oe: REN ety ERE IES KO Rage alone oh Nitya ek Rae Tree ek cate ah cunhets sc pdertetibleiiedinetanaaiding 3 har: P gy wine Mange aN BS nee i t? +e Lait ‘Vina ote, pemaat, cor ang mens} e 2 : er ey daeaght WHATand WHY and WHEN, and HOW and WHERE and WHO.", (tee) WHAT was the Declaration of London? | WHATare consols? : WHY does the date forEaster vary ff from year to year? WHEN and by whom was the great pyramid of Cheops built? HOW can you distinguish a malarial |f mosquito? WHERE is Canberra? Zeebrugge? |f Delhi? WHO was MotherBunch? MillboyY ; of the Slashes? i) Are these “six men"serving you too? Give them an opportunity by placing _ WEBSTERS NEw INTERNATIONAL in your home, office, school, club, shop, library. This “Supreme Authority” in all knowledge offers service, im- mediate, constant, lasting, trustworthy. Answers all kinds of questions. A century of developing, enlarging, and perfecting under exactingcare and highest scholarship in- sures accuracy, completeness, compactness, authority. The name Merriam on Web- ster’s Dictionaries has a like significance to that of the govern- EH ment’s mark on acoin. The New i) INTERNATIONAL is the final author- | ity for the Supreme Courts and the Government Printing Office at Washington. Write for asample page of the New Words, speci. men of Regular and India Papers, also booklet ‘*You are the Jury,’’ prices, etc. To those naming Popular Science Monthly we will send free a set of Pocket Mans. G. & C. MERRIAM COMPANY Springfield, Mass., U.S. A. eeecceees BETTER SHOP METHODS Making a Small Sheet Metal Punch Press ORK often done on sensitive (rill presses, such as drilling rivet holes in: thin sheet metal, could be accomplished more quickly and cheaply on a light punch press. Also, in the experimental departments and in the model building workshops of amateur mechanics, a small punch press is a handv tool. A punch can be made with little treuble if square bar stock is used fora frame. For punching sheet stock up to )¥ in. thick the power of a heavy ham- mer blow is STRIKE HERE WITHHAMMER Le By Robert S. Lewis blanks to fall through. The upper part of the frame is mounted squarely on the pillars in line with the lower part and is slotted for the adjustable guide bolt. It also igs drilled on the forward end for the %-in, punch holder spindle. This punch holder is flattened on its front face and is held from turning by a 5/16-in. screw and jam nut. On the punch holder is a special collar, which carries a thread for the punch retaining screw and also serves to prevent the punch holder from flying out of 1 “ 4 sufficient; this 7 its hole. does away lie PUNCH HOLDER S".4"cap A rather with the need t | jai SPRING 6 screws heavy spring for cams or : * 34 SLOT 15 | is placed be- toggles. Bs ° \ m x twee . the The main Ak conical head frame of the | “iq of the punch Ky "e is 1 a ] ns r and made of two \ i! a e frame 114-in. square GUIDE f PIvor ! 4 wo top. It cush- pieces of steel “i ions the blow connected A after the with two %- PUNCH YY in.cap screws, : HOLE which run FRAME, cane punch has gone through the metal and through the two round pillars, as INDEX PIN returns the punch and spindle to shown. The their upper 3- pillars are - turned and drilled out of cold —_ WY rolled steel shafting. ‘374 = The bottom part of = the frame is mounted on an iron _ base, a ft which is secured to | the workbench by lag I screws. nie While individual ee ge ten punches are usually + Aap PUNCH necessary, a single PUNCH SCREW piece will answer for the dies. This die plate, made of tool steel, is fastened to lower member of the frame with a 1-in. flat head machine screw. It is indexed by means of a small index pin. In mak- ing this die plate, drill all the index holes as accurately as possible, clamp the die plate on the frame, and by using a sharp center punch in the punch holder, mark off the location of the holes; then drill and ream them to actual size. Square, triangular, or any shaped holes can be made in the plate. A %-in. hole central with the punch will allow the = at ae YWMUUUGi kK 7 - How this useful light punch press is put together, and details of the ‘ screw, and die plate position. To the side of the upper frame is fastened a sheet metal stripper, which holds the metaldown when the punch is being drawn up through the punched hole. An adjustable guide is used to punch a line of holes equally distant from the edge of a plate. This can be removed so that there will be a total clearance of 31% in. The hammer used to operate the punch should weigh about 5 lbs. Punches are made of %-in. drill rod suitably hardened and drawn. The die plate is machined up and also hardened and drawn; it should be a good grade of carbon tool steel. While this is a simple piece of mechanism to build, it will prove a valuable tool and will be appreciated by the workmen because of its small size and large capacity for work. DIE PLATE unch, punch Leather Strip Prevents Screw Jamming 7 IS sometimes necessary to make a cap similar to that shown in the illustration, the outside having to be turn- ed up smooth in a lathe. Where there are quantities to do, make an arbor to fit on, or in, the spindle of the lathe. Where there is but one or two to make, chuck a piece of scrap cast iron in the lathe chuck and make a temporary arbor. Place a narrow strip of leather around the collar or ring, so that one end can be pried arbor between the shoulder on the arbor and the face of the cap. Then, when the job is done, pull out the leather and the cap can be unscrewed with the fingers. pressure of the cut from forc- ing the cap against the shoulder of the arbor so tightly that it is difficult to remove without marring or damaging it. Be sure to use a strip of leather, not a up and the strip taken off easily. —W. D. T, a This method prevents the | A Popular Science M onthly | t \ Blarch, ig |

Page 77

eS nw OS a 8. Se eS SS Oe ee a: ie a | — - —_—- ae —~j- Barch, 1923 =. a a. a | Make Your ’23 Vacations Evinrude Outings OU men, whose happiest hours are spent with rod and gun—you, whose families “rough it’? each summer at the waterside, camping, bathing, picnicking—you, who motor from lake to lake, fully equipped to ‘‘week-end” where you choose—now is the time to plan this year’s outings around your Evinrude. If you have ever used or owned an Evinrude you know what a faithful- vacation pal this husky little outboard motor is. Just feed it a quarter’s worth of ‘‘gas’’ and oil, give a fling to the flywheel and you’re all set for a twenty-five mile trip, without oar-work. No need to worry about the size of the load—your Evinrude has plenty of power and speed. And, as any of the 150,000 owners will tell you, a genuine Evinrude is built for ten years of dependable service. Many sportsmen who prefer a permanent installation are equipping their rowboats, canoes and launches with Evinrude Inboards. Easily installed, light and compact, both the one- and two-cylinder Inboards are ideal for small-boat power. See the genuine Evinrude models at your sporting goods or hardware dealer's. There's an Evinrude for every small-boat use. Orwrite for free catalog. EVINRUDE MOTOR CO. 125 Evinrude Block, Milwaukee, Wis. i DISTRIBUTORS: ae Ev 69 Cortlandt St., New York, N. Y. 780 Commonwealth Ave., Boston, Mass. 119 Broadway, Oakland, Cal. 211 Morrison,St., Portland, Ore. in and Sp Single Cylinder Twin Cylinder inrude Inboard Motors — Like the Standard Evinrude Outboard struction. miles per hour. Especially fitted for use in canoes. Develops speed of 12 miles per hour in 18 foot canoe. Both models have Evinrude built-in flywheel magneto. 91 . = : design con- eed 7 noe mae set AbeC ia te 3 3 eae ye cer ae

Page 78

BE le AT, Diag Ti. ater eee eee wine Ae, TRESS 9 ero Ge seas ei Buare ° SS sp a clas Sha I POSNER MT GANGES i Sh gn mth te ne BORA SPORE: MC? TAM RE HST eg joo Pia a apt Ae i wear Aufcte or Leger sues soiree jls ais eerste ohm aieaareneest cpa OY : per A ce ka - mR Saad a het ae iy boas Sokmetade aiid Ya pric sai td! 2 f 34 oH “ er NNER anus tee Pelee etl eerie ee BT Cr Wu Bute Mah bs bg 5 (a) ae TZN Any Musical Instrument Bi) a7 "> Trial : S yments Wag A few cents a day will pay. Instruments and complete outfits at factory prices direct to you, rr b te See The Rudolph Wurlitzer Co., Dep. 1783 | 117 E. 4th St., Cincinnati —329 So. Wabash Ave., Chicago | 120 W.42ndSt., New York —250 Stockton St., San Francisco Send me your new catalog, which illustrates and j describes every known musical instrument, many of them shown in full colors, all at lowest factory | prices. Also tell me how I may have any instru- i ment on a week’s trial in my own home at your expense and without obligation, and may pay for it on your special easy payment plan. (State instrument in which you are cepecially interesied) Le gums Copyright 1922, The Rudolph Wurlitzer Co. cums cama BETTER SHOP METHODS Attachment Cuts Worms and Keyways in the Lathe By James Ellis [|e popularity of worm and wheel re- duction units among designers of vari- ous classes of machinery has made it neces- sary for our shop to make a great many worms at various times, and we felt the need of a process more efficient than chas- ing, yet not requiring costly equipment. The writer therefore designed the attach- ment illustrated. Since it was built, other uses have been found for it that are.almost as valuable as that for which it was de- signed. The device is simply a milling attachment for the lathe. The spindle is arranged to take asmall end mill the shape of the thread to be cut, and the lathe is geared for the correct lead, as in chasing. Power for the cutter is provided by an electric drill SfT- CLAMP BANDS SCREWS yor st =| c ° = REL, hoes WORK A : ‘oll HOLE CONNECTOR 6 ob SD Nicer SYS MAA Say 8 N°2 MORSE HEAD TAPER FILE CLEARANCE Ore CUTTER ‘ This small milling attachment, with its motor, is mounted on the compound rest of the lathe clamped to a bar. nected with the cutter spindle with a small universal joint. The average electric drill found in machine shops and garages has ample power for this work. The head of the attachment is cast iron. It is provided with a key to fit the slot in the compound rest of the lathe. The dis- tanee X is made to fit the lathe to be used, the spindle of the attachment must be the same height as the lathe spindle. The type of bearing for the spindle may be varied to suit the builder, but a tapered bearing as shown is probably the best if carefully made, as it permits quick and accurate adjustments and at the same time is very rigid. A steel or bronze washer is doweled to the head and behind it are several washers of thin metal or paper, which are taken out when wear occurs to let the spindle go deeper into the tapered hole. On the other end of the spindle two adjusting nuts are provided. A hole is drilled to take the 1-in. bar to which the electric drill is clamped. Set- screws hold the bar in place. A hole fora to the tool block of the lathe is drilled close to the center of the casting. The steel spindle has a shoulder on one end to take the end thrust and is threaded at the other for the adjusting nuts. The hole in it is bored to fit a No. 2 Morse taper shank and a 7/16-in. hole is drilled through to take a draw-in bolt with a thin head for securing the cutter. The back end of the spindle is 5 (Continued on page 94) The spindle is con- | large headed bolt to fasten the attachment | c DAP eae rem oe os Ree . a 1 i ly a - 2 — ., Good » AtCCejyj a9 Set O own a good receiv- ing set without Mag- navox equipment, is like having your house prop- erly wired and then using only small, feeble candle- power lamps in the sockets! Whether placed in theav- erage living room or large dance hall, Magnavox Radio floods the desired area with clear, resonant music or speech—its vol- ume perfectly controlled from the Magnavox Power Amplifier con- structed specially for it. Combination R-3 Repro- ducer and 2 stage Power Am- plifier (as illustrated). R-2 Magnavox Reproducer with 18-inch horn: the utmost in amplifying power, for store demonstration, large audi- ences, dance halls, etc. R-3 Magnavox Reproducer with 14-inch curvex horn: ideal for homes, offices, etc. Model C Magnavox Power Amplifier insures getting the largest possible power imput for your Magnavox Repro- ducer. 2 stage; 3 stage. Magnavox Products can be had of gdod dealers everywhere. The Magnavox Co., Oakland, California New York: 370 Seventh Avenue Write for booklet illustrating and describing the IAGNAVOX Radio The Power Amplifier and Reproducer Supreme Popular Science Monthly . Mare » 41

Page 79

>CelV- Mag- : like prop- using indle- the heav- large navox esired onant ; vol- rolled avox con- for it. Repro- ver Am- oducer utmost or store audi- oducer rn: ideal Power ting the r imput Repro- ge. had of Te. Q Co., nia Avenue ng and IX fier reme -

March, 1923 SIX SENSES Seei’ ng ~ Jeeling~ VHearing~ Smelling Jasting and ~~ Tycos Temperature ea

COS ?¢ 93 THE SIXTH SENSE OF INDUSTRY Jemperature Control cc You Hear Famous Artists— Thanks to the Pre a record on your phono- graph, drop the needle into place and the glorious tones of a famed tenor fairly shake the walls, the soft melody of a woman’s voice charms the twilight, or the machine recreates the sound of violin or piano. You perceive these things by the sense of hearing, to be sure. But, behind the miracle that reproduces the sound waves, lie years of past toil and present accuracy in the perfection of every detail of the phonograph and record. Consider the record itself. Itisa tough, elastic sub- stance, composed of certain compounds that must be accurately blended. In this process, heat is employed. The control of this temperature must be exact if the finished “‘blank”’ is to prove properly susceptible to reproducing the sound waves when it is pressed by the master record. Behind the making of this master record itself—behind every step in its plating and electro- “Sixth Sense’’ plating, clear back to its production as a plaster cast of the original wax im- pression of the original harmony, the control of temperature—the “‘sixth sense’’—plays its silent but vitally important part. The record of Tycos Tempe ature Indicating, Recording and Controlling Instruments furnish the means whereby this ‘‘sixth sense” has become as much a part of the everyday industrial world as the sense of hearing itself. The records you listen to are perfect because the records of the Tycos Instruments that controlled the temperatures employed in their physical production were perfect. Listen, then, to the voice of Ameri- can Industries—the voice that pro- claims the 8,000 varieties of Tycos Temperature Indicating, Recording and Controlling Instruments as the standard of accuracy. Their record extends over years of usage—in condi- tions that parallel your industry. eatery peat Manufacturers What is your problem of applying this “‘sixth sense’ to your plant? What do you make? Write us and literature on any instrument or type of instrument will be sent you promptly. T7'ycos experts are ready to advise on its application to your plant.

Ty fycos in the Home Treoe Stormoguide Forecasts the weather twenty-four hours ahead with dependable accu- Dicos Wall Thermometers = help you maintain a —— urein or house ucive to good health. Zeos Quality Compasses Office Thermometers An aid in promoting human efficiency. Froos Bath Thermometers To enable you to get the To now you the jight Iycos Hygrometer most good from your bath, so To enable you to keep ee. L~ humidity of Ms atmos- Troos Home Set phere in your home cor- Bake Oven Thermometer. L rect at all times. Candy Thermomete:. Sug- ar Meter. The secret of ac- curate results in cooking. Ask us, on a postal, Troos Fever Thermometers Necessity in every ln Your dealer will show them to you. for booklets on any of the above. TYCOS and the MEDICAL Profession Zeoe Sphygmomanameter, Pocket and Office type Zece Urinalysis Glassware. Zeoe Fever Thermometers. Bulletins on Request.

Taylor /nstrument Companies Main Office and Factory ROCHESTER, N.Y., U.S. A. Canadian Plant TYCOS BUILDING TORONTO CANADA

Tycos Tem perature/nstrumen ts pn ote ‘RECORDING CONTROLLING

~e

a = Ee res Oi Soe.

ees ee ee

Page 80

ea > Popular Science M. onthly Mare BETTER SHOP METHODS a , Attachment Cuts Worms (Continued from page 92) squared or “‘hexed”’ to fit a socket wrench and made to fit loosely over the end of the spindle. This is to give a certain amount of flexibility to the connection so that the drill need not be alined exactly and to per- mit the motor to be removed with very little trouble. The socket must be dee enough to go over the head of the bolt and the shank small an to go in the drill TT ; chuck. 1 slain Aaa The cutters are imade of tool steel. For | ig FSS the smaller sizes they are two-lipped; the wet. larger ones have three or four teeth. The | cutters are all made to the standard in- cluded angle of 29 degrees and vary for the different pitches by the size of the smail diameter Y. How the Device Is Operated After the attachment is bolted to the tool | block and the drill attached, the lathe is =~ cS ile I “HARDING - We venture to predict our President will address the nation Let Tuska Reliable Radio make you a part of his audience Tuska Quality Radio Apparatus means a Peg NE lifetime guarantee of reliable service back geared and the gears to give the cor- oo ae Ask for Tuska Radio at your dealers rect lead are put on. The blank is put be- Keceieing ee today. tween centers and the cutter set to cut the Beings The C. D. Tuska Company correct depth by measurement or by using x Ch Qeeeemew ave the micrometer dial of the lathe. The car- riage is run away from the work and the nut engaged. The belt is pulled by hand till | ? the cutter is almost up to the work so that | all lost motion in any of the parts is taken | up. Nowthe drill is started and the pull- ing of the belt by hand continued. Asthe cutter enters the work, the behavior of the | motor will tell whether the feed is too fast | or too slow. If the feed is too fast, the drill will slow down, giving warning and protecting the cutter from breaking. Care should be taken to see that the feeding | } is regular and continuous. Do not jerk the belt. On small worms only one cut need be taken, but on coarse pitches it is CHEMICAL APPARATUS _— nh we — ~— cuts. e thread is multiple, the index- LABORATORY SUPPLIES ing is accomplished in any of the usual and CHEMICALS ways, such as moving the carriage a defi- Send for our free illustrated Price List No. 2 nite distance. In cutting steel a copious | § BAKER & UNVERHAU, Queens, L.I.,N.Y. Hartford, Connecucut TUSKG RADIO Established 19]] ra ee) 5 ; iS bee jar te - ve EB & 4 5! ie , ay) ute 4. : hs Bi a ea a t 5 oe ee 3 Sof = § Pe Se supply of oil or cutting compound should be directed on the cutter. Sn BR ct ay Piao An dE AEN ERENT ce OM ae t : Cuts Splines and Keyways i Think of it ! = 75 paid to F. L. Bennett, i we N. Y., for one mechanical The Finger Print Another use to which this device is put ~ rawing. is cutting keyways and splines in shafts. Tapered shafts, which are troublesome to | » set up on the milling machine, shafts with gears of other projections in place, may be | | keyseated without trouble with this device f) eart of an_in- by using a small end mill. ’ other Sy Any young man can easily duplicate Bennett’s success by practicing at home like he did. You, too, can become an expert draftsman if you are ambitious. A new, simple method of drafting puts the big Jobs within your reach. Master Draftsman Bitting will show you how. You beginto DRAW at once. No long and tedious study, Bitting on n the Gun ~ Two shots rang out in the iat ness with but a Biue Print 12ct¢'s big. money in blue print reading, and you R ea d i n g can perfect yourself in this important and profitable work without learning to draw. Costs Nothing to Find Out Write today for our free offer on professional draftsman’s outfit. Find out how you, too, can get $175 for a single drawing or become a ‘blue print expert. Send for FREE book ‘‘Language of the Engineer."’ Address MASTER DRAFTSMAN BITTING Dept. 253 15th and Wallace PHILADELPHIA, PA, Be a Finger Print Expert More men are needed every day. But only trained men are wanted. We will t train you at home in your spare time, as we have trained many of ica’s greatest experts. Big Money to Experts * ne os for ‘‘wanted’’ man U epee; opportunities for a professional business ete your own. Write at once. Get Special Offer Now Pissic Act our Free book on Finger Prints, full of true stories of crime —— = ved by our uates. Free ——— Free course in Secret Intelligence if you pond now. Write today. 1920 sale Ave Dept ss00c 1363, Chicago te ce MB Sig wey nome We have built another of these attach- ri ; . A ments to fit a large lathe, 32-in. swing, and Drawing Outfit lingescape through the attachment is used almost exclusively But behind lay the for keyseating. Large work that has been ; ar Gis tes taltake turned up can be keyseated before being a E E | ee a taken out of the lathe, which effects a con- * smooth, bluedsteel. siderable saving of time in handling. Such To those who act at once we offer a complete tallsat the oxph exploits work as heavy rolls too large to put on terry car nepal eter oper tome Ag pee the milling machine table, complicated and «°° . Sete Wis cumbersome parts, such as dough mixer beaters or multiple throw crankshafts, may be put between centers and keyseated in a short time. This large attachment takes cutters with No. 3 shanks, has a worm and wheel drive of 10 to one ratio, to give more power to the cutter, and the electric drill stands parallel to the lathe axis. A SLIGHTLY glazed emery. wheel will produce a high polish on the work. An ordinary pebble rubbed on the wheel will produce the propepelaze for this purpose.

Page 81

fonthly rench of the nount it the D per- very deep t and » drill . For ; the The ‘d in- or the smail | e tool the is e cor- ut be- it the using ie car- ne nut id till o that taken | 2 pull- | As the | of the 00 fast st, the ig and Care -eding it jerk ne cut 3 it is n two index- usual a defi- opious should is put shafts. me to s with ay be device ttach- g, and sively s been being a con- Such ut on od and mixer 3, may seated hment has a tio, to d the e axis. | will An a] will rpose. March, 1923 | jpeerengeeimairse gyn DING its light weight, the Elto is the most powerful outboard motor — not just according to someone’s “say-so”, but by actual piston displacement. You need this extra H. P. to get speed from ordinary substantial boats—to buck river currents or headwinds and to carry loads. The Elto is the fastest most Easy starting and safety steer- ing make it the family motor. You'll find no hard, stubborn start- ing with the Elto, because its Hot- Shot, waterproof battery gives it a spark so intense—so big and powerful, independent of cranking speed, that anyone can start the Elto with a quarter turn. Safety Rudder Steering — does away with all possibility of danger- ous pivot turning — lets you steer with tiller rope from any part of the boat — frees your hands for rod or gun except at turns — frees them from constant holding to a tiresome, shaky steering handle. Fastest on any type of boat. The Elto has proven beyond all dispute to be the speediest, most powerful outboard motor. Wherever stock models are used, Elto leads in speed. powerful light weight motor. As light as right. Ole Evinrude, the pioneer outboard motor design- er, who builds the Elto under per- sonal direction, can be trusted to find that point where light weight, power, speed, and durability meet — to build light, but with no sacri- fice of power, speed, bearing or wearing surfaces. Qle Evinrude has built years of trouble-free service into the Elto. Ask for this, his latest motor, by name—the ELTO. The fast, light, easy-Starting, vibrationless, 3 H. P. Twin. Grease-tight gear housing— silent underwater exhaust — quick reverse — weedless construction— folding rudder. Goes into carrying case without taking apart. Sym- metrical design, beautiful finish. Write for catalog. Dealers and Demonstrating Agents write fur proposition— some good territory still open. Elto Outboard Motor Co. Milwaukee, Wis. Dept.AA, Mfgrs. Home Bldg. Li ght Twin As light as right” 95 Go Where the Fish Are Throughtherushesandthelillies—thesnaggy ~ bay and rocky channel— go anywhere. The Elto is weedless and it safety-tilts when the propeller protector hits rock or snag. No in- jury to motor or boat. Go where the fish arel Safety Tilting and Floating Type Propeller Shaft Prevent Bearing Wear I have found in outboard motor building that disalignments of shaft and gears cause strain, severe wear and consequently short life. This has been eliminated in the Elto by the unique construction of its one-piece lower main frame which takes all shock and strain from the shaft in the same way as in the float- ing type automobile rearaxle. The main frame houses the drive shaft in a way that protects it from all possibility of disalignment.”

Page 82

| | $20°°aWeek Wouldn’t Stay Down E was putting in long hours at un- skilled work. His small pay scarcely lasted from week to week. He saw other men promoted. Then he learned the reason. They had special training. He made up his mind to get that kind of training. He sent to Scranton a coupon like the one below. That was his first step upward. The reward was not long coming—an increase in salary. en he was made Foreman. Now he is Superintendent. It just shows what a man with ambition can do! What about you? You don’t have to stay down. You can climb to the position you want in the work you like best. The way to do it is easy—without obligating yourself in any way, mark and-_mail this coupon. INTERNATIONAL CORRESPONDENCE SCHOOLS Box 7631-C, Seranton, Penna. 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: BUSINESS TRAINING DEPARTMENT Business Management OSalesmanship . } Industrial Management Advertising fF} Personnel Organization Better Letters F)Traffic Management Foreign Trade Business Law Stenography and Typing Banking and Banking Law Business English Accountancy (including C.P.A.) [ Civil Se rvice Nicholson Cost Accounting tro Mail Clerk Bookkeeping mmon School Subjects Private Secretary High School Subjects Business Spanish [) French Dlustrating TECHNICAL AND ae eee ENT A Electrical Engineering tect Electric Lighting Blue Print Reading Mechanical Engineer Contractor and Builder Mechanical Draftsman Architectural Draftsman Concrete Builder Structural Engineer Chemistry () Pharmacy Automobile Work Machine Shop Practice Railroad Positions Gas Engine Operating Civil Engineer Surveying and Mapping Airplane Engines Metallurgy Agriculture and Poultry Steam Engineering 0) Radio Mathematics PEBGIB 00 scc0ccevccccsccesssvcccovovescopepesepeesecvesoscoseeneneseseovetvesscscosescees 6-26-22 IN areccclsccayevetbyecoreysineabeuntsosespveceesbesstbeiessbesshens phonies Persons residing in Canada should send this coupon to the International Correspondence Schools Canadian, Limited, Montreal, Canada. bet HOME” ‘OU can make $15 to $60 weekly in your spare . time writing show cards. Np canvassing or soliciting. We instruct you by our new simple tograph system, pay you each week and guarantee you steady work. Write for full peewee - te al et. WEST- OW CARD SERVICE 63 Colborne Building Ti % Own a Home SA) Workshop! CI Build Radio parts, We supply shafti»g, pul- leys, hangers, belting, motors and supplies. Don’t waste time on makeshifts. Order good supplies. We also manufacture bench machines Write for Prices, HESTON & ANDERSON, Fairfield, Iowa. BETTER SHOP METHODS Adapter for Lathe Tailstock Holds Small Drill O HOLD small drills in the tailstock of the lathe ordinarily requires either a small draw chuck or a wrench chuck with a Morse shank to fit in the spindle. A special adapter, made as illustrated, will take the place of such a chuck. It is a simple piece of bar stock turned with a Hanson SHANK TO FIT MORSE TAPER, } TAILSTOCK \ s OF LATHE..: Whbd DRILL MOUNTED IN SPECIAL ADAPTER e—— ‘ss ( => —— \ ed Simple in construction, this adapter serves as a chuck for small drills Morse taper shank and drilled with two holes, as shown, to accommodate the drills. The forward hole can be made to fit a 14-in. drill and the small hole a 1¢-in. drill. Other shanks can be made to accommodate other drills, if necessary. The hexagonal end is for the purpose of taking the tool out of the spindle, while the lengthwise slot, which nearly severs the shank, allows the two sides to grip the drill when the shank is driven into the spindle hole. This unusually simple adapter is readily made up and saves much time and inconvenience in mounting a drill.—G. A. Clamps Quickly Made from Short Lengths of Channel Steel - EVERY shop large clamps, small clamps, wide clamps, and all kinds of clamps are constantly in demand. Good serviceable ones may be made from ends of structural channels. These are cut up in convenient lengths and tapped for one or two setscrews, as shown. The screw is then used to clamp the work against the ONE OR TW HOLE O SETSCREW __—_——_ nal ag SMALL AND LARGE SECTIONS ALL FORM CLAMPS FOR SOME PURPOSE Oy WORK TO § @7p BE_DRILEED 3 USED ON THE BENCH TO HOLD LONG STOCK Waste channels serve for cutting clamps of various sizes opposite flange of the channel, and for fine work a block can be interposed between the work and the point of the screw. For holding work on the drill-press table, for securing parts together while riveting, for holding long stock while sawing, and for hundreds of other purposes, these clamps will be useful. Whenever a length of channel is available, it is well to seize the opportunity to make one or more.—M.B.K. House DSO You can buy all the ma- terials for a complete home direct from the " manufac. turer and save four profits on the lumber, millwork, hardware and labor. ROOM *1068 HOUSE Prices quoted include all lumber cut to fit, windows, doors, wood- work, glass, paints, hardware, nails, lath and roofing. Com- plete drawings and instructions. Many styles to choose from. Hightest grade Jumber for all interior wood- work, siding and outside finish. Send today for money-saving Aladdin Catalog No. 2339 BAY CITY, The ALADDIN Ce., MICHIGAN Also Mills and Offices at Wilmington, North f Carolina; Portland, Oregon; and Toronto, Ontario bie Sebring ~ orida Hears Honolulu ~ awaii The remarkable | results achieved with Crosley Radio Instru- ments are equaled only by their exceptionally low cost. A man in Sebring, Fla., using a Model X Crosley In- strument—Price only $55 for this four tube set—writes: ‘‘We are receiving from all standard stations north, east and west— from Winnipeg, New York City, Seattle and one night received three selections from K. D. Y. X. at Honolulu, Hawaii.”’ From our one tube regenerative receiver at $16.00 made for us under license under Armstrong Patent No, 1,113,149 to our beautiful console Model XXV at $150, Crosley Instruments offer the highest efficiency at the lowest cost. Storage batteries unnecessary. Listen In On a Crosley and Be Convinced. Sold by Dealers and Jobbers Everywhere. Write for this free Catalog a a “i CROSLEY MFG. CO. 317 Alfred St., Cincinnati, O. cROSLEY ne Better =-Cost Less _ | Provucts RADIO — A DAY AHEAD of the Headlines of tomorrow's newspapers ! Don’t be satisfied with the regular broadcasted programs! Get the most out of radio! Hundreds of radio enthusiasts are doing it! Equip your vacuum tube set witha FINCH RADIO RELAY arid you will automatically receive and at the same time have a permanent record of all the im portant and interesting news events of t world, whether or not you know the code Oars FINCH RADIO MFG,CO. 303 FIFTH AVE.NVY.CITY.

Page 83

March, 1923 a a a Good Tools for the things to be made and “fixed” DD jobs of carpentering and tinkering. Always bobbing up—aren’t they? You'll sidestep them, every time, if you have to work with poor tools. You'll tackle them, every time, if you have workmanlike tools to give you a lift. And you’ll do a job you’re proud of. For 55 years we have been making tools as well as we know how. Today it.is safe to say there is not a community in all Christendom where Millers Falls Tools are not used by people who respect fine tools. Pick up a Millers Falls tool the next time you are in a hardware store. You may not be a master mechanic, but you don’t have to be to know that Millers Falls tools are a joy to work with. They have the “hang” and balance that only good tools have. MILLERS FALLS COMPANY Millers Falls, Mass. Manufacturers of Carpenters’ Tools, Hack Saws and Automobile Tools MILLERS FALLS en ——. . = CX REE i ee ee

Page 84

EINE SE ONS CGM MANES ST mS eB Tee einggt = NON ENS silin APCOMERATR P C: 7 3 - 8 Paylin © % ™ ooo. , ‘uvaivatic an vieh hie 8 SE eee —- a PRY a 98 Popular Science Monthly RADIO POPULAR SCIENCE MONTHLY Will Furnish a Reliable Blueprint number of _ Parts. Should Receive 500 Miles Under favorable conditions, if a long, high aerial is used, this receiving outfit will receive 500 miles. The blueprint contains working drawings, instructions, Popular Science Monthly, 225 West 39th St., N. Y. City Enclosed is 25c for which please send me the blueprint of the two-stage regen- erative receiving set. » 0 8 8-0 6: 6 0s © © ee 00000066808 60 ee 6 8 SD carve la a EES ai For men who like to make things at home with tools POPULAR SCIENCE MONTHLY is now publishing, in addi- tion to its popular woodworking plans, an invaluable radio blueprint. This blueprint is easy to understand; the receiv- ing set described requires the purchase of the fewest possible The vacuum tube set with two stages of amplification, from rear of pane and bill of materials of a two-stage re- generative receiving set that a profes- sional would be proud to own. It com- prises a variocoupler and an Armstrong two-variometer-regenerative tuning cir- cuit coupled, if desired, with two stages of audio frequency amplification. The tuning coils have been selected be- cause of the ease with which they may be constructed at home. In this set has been incorporated the best features of several types of outfits. It will tune from 180 meters to about 600 meters with remarkable sharpness and selectivity. LEYS , TURY f cclPt proce SSES. AND — ' TWENTIETH CENTURY Book of Recipes, Formulas and Processes This book of 800 pages is the most coinplete Book of Recipes ever published, giving thousands of recipes for the manu- facture of valuable articles for every-day use. Hints, Helps, Practical Ideas and Secret Processes covering every branch of the useful arts are given. 10,000 Practical Formulas—The Best Way to Make Everything A book to which you may turn with confi- dence that you will find what you are looking for. A mine of information, up-to-date in every respect. Contains 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 225 West 39th Street, New York How to Make Things Electrical Have the fun of doing it ' yourself and save half the cost This book gives directions for making hundreds of electrical appliances and devices for the home, the shop and the garage. The simple directions and many drawings make the work easy. 429 pp. Price, $1.90 post paid. POPULAR SCIENCE MONTHLY 225 West 39th Street, New York City Throttling | Governor 5 —— ENGINE Simple—Wonde Runs on either Kerosene, Gasoline or Distillate. Starts without cranking. Vary_power at will. Mechanically rfect. Years Ahead—Dollars Better. New Catalog FREE — Shows all styles. Cash or Terms. Write us. WITTE ENGINE WORKS 2220 Oakland Avenue, © KANSAS CITY, MO. 2220 Empire Buliding, e PITTSBURGH, PA. 131 Fremont Street, - SAN FRANCISCO, CAL. vs LP WRITE JOKES ¢ Easy, fascinating work. Our sales de- partment pays from $1 to $5 for jokes, epigrams and stories. A short course of three lessons teaches you how to write them. One joke alone often pays for the course. Humorists earn big pay. Get into a field that is not yet crowded. Write for information. AMERICAN INSTITUTE OF HUMOR ¢\ Office K, 414 Park Bidg., Cleveland, O. BETTER SHOP METHODS Block Fixture for Forming Flanges on Copper Pipes SUCCESS in making gasoline and oil line connections that will not leak depends mainly upon the flanging of the copper pipe. A shallow or an uneven flange igs difficult to draw up firmly enough to pre- vent leakage, and there is danger of strip- ping the thread from the coupling in an effort to tighten the joint. A fixture made as illustrated will flange the pipe to form a perfect seat and yet save considerable time over methods that involve the use of a hand flaring tool or SETSCREW WITH CONICAL POINT—a— HOLES DRILLED .02" LESS THAN PIPE SIZE Conical point on setscrew flares pipe for making gasoline and oil line connections punch and hammer. The device consists primarily of a block in which holes have been drilled of diameters slightly less than the stock sizes of pipe. These holes are countersunk and the block is cut in two after other holes are drilled and tapped for screws to hold the sections together. A block shaped like a square C clamp is _ made to fit over these parts. A 1-in. set- screw is fitted into the clamp, as shown, and the end of it is ground to a conical point. It is then only necessary to place the pipe in the fixture and screw down the setscrew. The pipe will not split unless it is hard, under which circumstances it should be annealed by heating and quench- ing in water.—L. D. J. Special Lathe Tailstock Tool F gphieeaetecn many mechanics use only lathe tools erected in the toolpost of the lathe cross head, special tools for dupli- cation work set into shanks fitting the tail- stock are often advantageous in that tools SHANK TO FIT TAILSTOCK TOOL FITTED”) INTO TAILSTOCK Saves time in simple duplicate lathe work for different purposes are made available without changing one for another. For example, a large number of disks with a threaded shank were to be lathe turned. A shank was turned to fit the tail- stock and one end of this was left large to accommodate a setscrew and tool. A suit- able side cutting was then made as shown. The same shank could be used to hold tools of other shapes.—F. M. H. M ar

Page 85

Fe em Ye Ue — Ww March, 1923 Radio Insulation that has the Call! we: radio parts and supplies are sold, Formica is called for by buyers, or is instantly accepted by them as being a radio insulating material that has no superior. That is due to the nation-wide reputation for quality which Formica has won. It is used exclusively by many makers of radio sets of the finest grade. Experienced amateurs everywhere hold it in the highest respect. ; In color, in beauty and uniformity of finish, Formica has for many years had no equal. It works splendidly with ordinary tools—maintains the highest dielectric — and gets better with age. Send for these leaflets: ‘“‘What Formica Is” tells the story of the different grades of Formica for all sorts of electrical and mechanical uses. “Noiseless Non-Metallic Gears and Pinions,” describes the mechanical uses of Formica in automobiles and machinery. “Unbreakable, Oil Proof Pump Valves,” deals with Formica discs and balls for use in pumps. “The Popular Insulation for Radio Panels and Tubes,’’ discusses the radio uses of Formica. DEALERS :—The policy of the Formica Company is to co-operate aggressively with the jobber and dealer. You get prompt shipments, and high grade printed matter and sales helps for your store. THE FORMICA INSULATION COMPANY 4630 Spring Grove Ave. Cincinnati, Ohio SALES OFFICES 50 Church St., New York,'N. Y. Sheldon Bidg., San Francisco, Cal. 1210 Arch St., Philadelphia, Pa. 422 First Ave., Pittsburgh, Pa. Whitney Central Bldg., New Orleans, La. 313 Title Bldg., Baltimore, Md. d 1042 Granite Bldg., Rochester, N. Y. 414 Finance Bldg., Cleveland, Ohio 1819 Lyndale Ave., S., Minneapolis, Minn. 415 Ohio Bldg., Toledo, Ohio 9 South Clinton St., Chicago, Ill. 47 King St., Toronto, Ont. 99 ORMICA Made from Anhydrous Redmanol Resins oa TUBES RODS seme ceee msvsannue meremne pen f 5 ase et ata a AOE OES 8 IE ne row pe ewe =

Page 86

PEC RAIPE TEN AE TN NIE UT RB FS nL woman & Maggs wm sicdipi ME ad NERO a: g —_—_—_— ‘ RANE | PR “He ESE ERE OR CRETE MEK Tait 18 “ at - See Sy tha HeKiees i PE ali Saco nid RT PN I YP: Pn Be LIE ig hy nd 9 Sea OL ml nae Si tien HF a | pe ra nae =, ge oes Keeps His Eye on The Score Any game a man plays, his eye is on the score. It’s the same when he's operating a machine. On the machine a Veeder Counter keeps the score. And your worker keeps his eye on it. Maybe he’s trying to better his. record—at producing. Maybe he’s only watching out to prevent a poor show- ing. In either case, his pro- duction is HIGHER because of a COUNTER The Set-Back Rotary Ratchet Counter below 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 4 size.) Set-Back Revolution Counter of similar model, $10.00 (list). Thissmall Rotary Ratchet Counter (No. 6) counts reciprocating movements of the lever, as required for recording the output of innumerable small machines. When the lever is moved through an 4 angle of 40 to 60 degrees, the counter regis- ters one, The further the lever is moved, the higher the number registered. A complete revolution of the lever registers ten. This coun- ter can be adapted to no end of counting purposes, by regulating the throw of the lever. Price, $2.00. (Cut nearly full size.) Small Revolution Counter, also $2.00. Everything you could ask ina counting device is shown in the new 80-page Veeder book- let. Ask for this foremost counter booklet. The Veeder Mfg.Co., 44 Sargeant St., Hartford, Conn. Popular Science Monthly : nc fy, q ae _— \ ee The r= y 5 PANG: co SANANG Home Workshop plated hinges may be used, and two heavy chest stays should be provided. Great care should be taken in finishing the chest. The cedar is always left in the natural color and requires merely to be varnished. If the mahogany is of a dark variety, it also can be left in the natural color, but ordinarily it should be stained either by applying a mahogany stain be- fore filling or by using a mahogany filler. If natural colored paste filler is darkened with burnt sienna, the result will usually give a brown mahogany color that looks well. If an antique mahogany finish is desired, the wood can be stained before filling with a solution of 14 oz. of potassium > hae gg BEVEL = x= STRIP AROUND ln = 8 © TOPOF COVER Le ee 36" A 8" > 2 SAIN i” CHAMFER-y 24 2 ls tre 173" ——> ¢ vs =| ~ == ZA STEELGLIDE 47° ROUNDED } —° = CORNERS’ ./' TRAY 17°24 y 4” DEEP) wry i 1k STRIP Sit FORTRAY TO + SLIDE ON — bial ra! Details of chest shown at the right bichromate in 1 pt. of hot water, applied cold. In any case, the mahogany should be filled with paste filler. Additional working details and bill of materials for this chest are contained in Home Workshop Blueprint No. 17 and will be sent anywhere for 25 cents to cover the cost of blueprinting and handling. One advantage in building a chest is that it can be designed to suit the space available. Sometimes commercial chests are too long or do not, in the smaller sizes, have sufficient capacity. It-was to over- come objections of this sort E. E. Scott of Pittsfield, Mass., designed and built the chest illustrated above. The lumber required is 26 board feet of ¥%-in. stock and 380 linear feet of 34 by 24- in. stock. The material is cut roughly to size and tongued and grooved at the mill for a small extra charge. The corners are not dovetailed, the tim serving to cover up the screws that hold the joints together. The first step is to match up the boards for the bottom, glue and clamp them to- gether and, after the glue is dry, to cut out a rectangle 3514 in. by 1734 in. The sides and ends are then built up, all being joined at the corners with 214-in. screws, countersunk. The corners are reinforced inside with 1-in. quarter round molding. The trim is then cut and fitted. The corner joints in this case are mitered and | the trim is attached with liquid glue and How to Build a Cedar Chest (Continued from page 78) 1-in. brads, the heads of which are cut off with pliers before the brads are set; then, when driven in, they do not leave large holes to be filled in finishing. Three stout brass hinges are used for hingeing the cover and two chains pro- vided to prevent its falling backward. A brass lock and handles are put on after the chest is varnished. A sliding tray 4 in. deep and 1 ft. shorter than the chest is pro- A neat and substantial homemade chest built according to details at the left vided. It can be covered with cretonne. The finish is three coats of varnish, each sandpapered, followed by a final coat that should be sanded and rubbed with No. 0 steel wool, and polished with powdered pumice stone and oil. It then should be rubbed with curly horsehair. Usually the inside shows the bare wood, but a good cretonne could be used in this case to conceal the wood and the fabric quickly becomes saturated with the delicate red cedar odor. This adds a distinctive feature not found in purchased chests. Two of many styles of chests made en- tirely of cedar are shown in the small illustrations on page 78. These are fin- A fully}, panele chest ished in the natural wood ,and are orna- mented with copper bands. Sizes that seem to be the most popular are 15 in. high, 19 in. wide, and 35, 40, or 44 in. long, and 17 in. high, 21 in. wide, and 48 in. long. ‘ The chest illustrated above is not so frequently seen. The sides and ends are paneled, the rails and stiles being %-in. stock and the panels 4% in. The box itself is 36 in. long, 16 in. wide, and 16 in. high, the lid and base extending 1 in. beyond the sides and ends. ie Hardware and trimmings for chests are shown in the illustrations on page 101. The larger handles have plates about 24%

Page 87

A A A.

Om Oct ee Ww 8s We Me

Hlarch, 1923 _——_——— 101

THE HOME WORKSHOP

by 514in. They are made in copper finish, brass, and bronze. One leaf of a chest hinge is offset 34 in. so that it bears against both the edge and the inside surface of the back of the chest. In some of the finer chests a continuous or ‘‘piano”’ hinge is used; this was the case in the original model of the “‘blueprint” chest. Stays and supports are made in both the styles illustrated and range from 6 to 14 in.

in length. Locks also vary in size, work- manship, and finish. Thin gage copper bands for trimming chests can be obtained in various sizes, the most common being 2 or 4 in. wide, 11, 14, 22, and 28 in. long. Most of.these bands have a satin finish and are lacquered to prevent tarnishing. Fancy designs are also frequently used. The one illustrated with the f openings is intended to be bent around chest corners. The two escutch- eons are stock designs, but it is a simple matter to cut original designs from the plain strips. Copperized nails are used ordinarily for attaching the strips. Trim- mings in imitation of old hammered copper | are also manufactured, All these supplies can be obtained through hardware dealers or manual training supply companies.

Coupon for Ordering Blueprints Blueprint Service Dept. Popular Science Monthly 225 West 39th St., New York GENTLEMEN: Send me the blueprint,or blueprints, I have checked below, for which I in- close....cents in stamps or coin:

No. Title Price 1. Sewing Table.......... ..25¢ O 2. Smoking Cabinet........... asc O 3. Book Trough End Table.....25¢ O 4. 30-ft. Monoplane Glider. ....50c O 5, Kitchen Cabinet............ 2c O 6. V.T. Radio Receiving Set...25¢ UO 8. Shaving Cabinet........... 2c DO 9. Arbor with Gate and Seats...25¢ O 10 Porch Swing ..... spleteeanezeve ase O 11. Bench and Tilt-Top Table...25¢ O 12. Electric Washing Machine...25¢ O $95 “Desi WaeOns..:.55.< sccsss css asc O 14. Toy Train, Horse, and House.25¢ 0 | 15. Home Workshop Bench.....25¢ UO | 16. Inlaid Radio Cabinet.......25¢ DO | 17. Cedar Chest, Mahogany | PUAMENAIOEIS Ge) 5 05.8 031% visors oe 2%e | 18. Telephone Table and Stool.25¢ [j | DPMEOINR A ORCA Rete al es ice aE Sega oe j (Please print) | WOMEN oe etches aicor cinerea cateoine err ate

“PLANK WITH CYPRESS AND YOU PLANK BUT ONCE." A Row Boat or a : Cruiser? Now is the time to build her but probably the First Thing for You 3 \ to Do Is to Write for cities FOR mis IS_AS the C ress Boat Book NATURAL AS BOATS FOR WATER.”

It’s the BRAND-NEW Volume 19, of the famous Cypress Pocket Library, 192 pages, 46 illustrations and a “standard authority on boats.”’ In it you'll find 4 Full Size Working Plans and complete specifications for building a ROW- BOAT, a MOTOR-BOAT, a STERN PADDLE- WHEEL CRUISER and a YACHT. All were de- signed by the foremost marine architects in their respective lines. You will also find suggestions and plans for building and operating a houseboat. And why non-rot, non-warp Tide Water _ Tess OF ee “The Wood Eternal” is the best lumber for boats, big or little. Plank with Cypress and you’ll be immune from the expense of those oft-recurring repairs that are such a bother to the boat owner. For all marine uses Specify “ALL- HEART GRADE” CYPRESS. It assures you sat- isfactory service in the highest degree and for the long- est period. Get all the facts. Write for free Volume 19 today.

Southern Cypress Manufacturers’ Assn. 1249 Poydras Building, New Orleans, La., or, 1249 Graham Building, Jacksonville, Fle. INSIST ON TRADE-MARKED CYPRESS AT YOUR LOCAL LUMBER £ e DEALER'S. IF HE HASN'T IT, LET US KNOW IMMEDIATELY. M A ‘Tease Moon fom US Por Orman

Page 88

tw On eh Sa COT A HN PTE TIS ates: tery eeerippeonitsyaah neoast fa ee ey Di pinto al pitted Reng 4 som Neb ni aR ests TPR NS + 2 fate a ae 7 21 Jewel Burlington, Cu LOOK! to the Second to Temperature to Isochronism Ad to Positions 21 and Sapphire Jewels 25 Year Gold Strata Case Your Choice of Dials— Including Montgomery R R. Dial) ew Ideas in Thin Cases, on“ OO “Down Only One Dollar Down will buy this masterpiece of watch manufacture. The balance you are allowed to Pay in small, easy monthly payments. Burlington —a 21-Jewel Watch — is sold to you at a price much lower eh an that of other age tgp watches, Besides, you have the selection of the finest thin model designs and latest styles in watch cases. Don’t delay! Write for the FREE Watch Book and our Special Offer today. Write While this Special Offer Lasts Get the Burlington Watch Book by sending this coupon, Find out about this py specia offer which is being made for y a limited time. You will know a great deal more about watch buying when you read this book, You will be able to “steer clear’’ of the ge watches which are no better. Rem Burlington is sent to you for onl: ou Dollar down, balance in small monthly payments, Send the coupon for watch book and our especial offer Today! Do not delay one minute! Popular Science Monthly Burlington Watch Co., Dept. 1363 19th Se. and Mar Marshall hall Blvd. Chicago, Lig mg Please aon tonite me seiloes chttontons and aid) your free book on watches with full - ti of your $1 down offer on the Burlington — We cock, Name Address THE HOME WORKSHOP - Cedar Lined Chest Has Double Lids HE feature of this neat and craftsman- like cedar-lined chest is two doors or lids that take the place of a large cumber- someone. These lids have the usual halved joint with a small bead on the edge where they meet at the center. The diamond in the center of each lid is carved to form a recess, as shown. This gives a grip by which to lift the lids without the necessity of using a handle that projects above the top. Flush brass ring pulls may be used in- stead, and if handles are desired at the ends of the chest, it is well to use flush chest handles, which can be obtained in various designs and finishes. at The chest proper L770 LIDS AT CENTER may be made of any ¥%-in. wood available. FRONT The lining is of cedar, % in. or thinner. Even cigar box wood will do, if no other can conveniently be obtained. The size of the chest shown is 17 by 17 in. by 2 ft. 9 in. This is a medium size chest and for a larger one the dimensions might be 17 in. high, 20 in. wide and 8 ft. long. Dovetail joints are used at the corners because a fine dovetail is always the sign of good workmanship and needs no em- bellishment and projecting moldings to en- hance its value. Many hand dovetails and ‘Wel | {"y | he VIIILILEMEEMEEEM Y 4 4 4 4 yl / } The outside of this a enny Se mnee Vii of any w » only 7 the lining being of red cedar. The gen- eral ogee is shown above and the details appear at the left DOVETAILS all machine dovetails are very much coarser than those shown, but for the best results these proportions should be followed. If it is not desired to go to so much trouble, a simpler type of joint may be substituted. Feet can readily be added and they may either be carved or plain blocks about 4 in. square with the edges slightly rounded and projecting % in. Screw the feet from underneath to the bottom of the chest at the corners.—A. E. Pipe Fittings Form Powerful Press A CLAMPING, gripping and pressing fixture of ample size is a valuable addi- tion tothe home workshop. It saves strain- ing the vise jaws, takes work that cannot be accommodated in the ordinary vise and does away with al | two pipe columns pass through the holes bored in the post and aresecured by nuts on either face. They support a cross mem- ber that is connected to them by means of elbows and has a cross pipe connec- tion in the center. the necessity of im- Threaded into this provising clamps. is the feed screw, 1" trated is made up od entirely of pipe fit- tings and can quick- The fixture illus- 4. | | ( the upper end of which terminates in a pipe tee and two lengths of pipe to ly be put together by any mechanic who possesses pipe cut- posrgR ters and threading — WORKBENCH dies. It is attached to a vertical post or to the bench, if pre- ferred. Two similar clamps on adjacent posts are useful when long stock is to be handled. A reinforcement of either 14-in. steel or iron plate is essential under the clamp. The A rugged, shea made fixture of wide utility in the small shop serve as the han- dle. The opposite end of the screw is fitted with a loose pipe flange secured with a pin. Variations from the sizes indicated may be made, and smaller or larger pipe and connections may be substituted. The joints are treated with red or white lead and secured with drive-fit dowels.—S.N. ‘“‘Best Idea’’ Prizes S A bonus for the ‘‘Best Idea” articles contributed to the March Home Workshop, the following awards are made: FIRST PRIZE, $15: Gladstone Califf, Richland, Iowa, ‘‘How to Remodel Old Furniture Profitably”’ (see page 104). SECOND PRIZE, $10: A.M. Smyth, Germantown, Pa., ‘‘Papering Ceilings” (see page 132). Both of the prize-winning articles con- tain exceedingly helpful suggestions for Awarded for March . the home worker. Mr. Califf shows that it is rarely necessary to throw away an old piece of furniture. No matter how “‘second hand”’ it may be, the handy worker can refinish it so that it will be both useful and attractive, ae proved by illustrations accompanying the article. As for the paperhanging suggestions in Mr. Smyth’s article, if followed care- fully, they will insure success in the one task that holds the most terrors for the home decorator—papering ceilings. Ma

Page 89

reer Ve March, 1923 108 [ Two New Members of the Red Seal Battery Family > Radio Sparkers, made in 3 sizes No. 221—2 cell. . $1.00 No. 262—6 cell,.. . 3.10 No. 282—8 cell... . 4.00 f.0.b. factories The Red Seal Radio Sparker, for operating WD-11 Tubes A special dry battery that lasts nearly 3 times longer /RADIO | SPARKER | ke ele sven sellin te me F YOU have been attaching a single dry cell to each WD-11 tube, there’s a better way. The new Red Seal Radio Sparker gives longer service. For example, the two-cell Radio Sparker No. 221, designed to operate one WD-11 tube will last, not twice as long, but 214 to 3 times as long as a single cell. Radio sparkers are a complete unit, light in weight and easily handled. They consist of special cells carefully selected and matched. All internal connections between cells are sol- dered within the attractive container and the famous Manhattan Spring Clip Connectors insure a quick, bull-dog grip with your receiv- ing set. The labels of all Radio Sparkers con- tain simple diagrams and complete instruc- tions for the “hook up.” When you think of WD-11 tubes, think of ‘Radio Sparkers.” This battery is the product of the oldest and largest national distributor of radio, also mak- ers of the line of famous Red Seal batteries for over 30 years. be a Fr (cz se Ignition [iste Red Seal a i anos? soe Price RED SEAL in 3 sizes ; 141—4 cell, $2.20 152—5 cell, 2.60 162—-6 cell, 3.10 f.0.b. factories The Red Seal Sparker— steel clad NOTHER step forward in battery building is the new Red Seal Sparker—steel clad— developed in the Manhattan laboratories. The container of this new battery is made of heavy open-hearth steel and will not only withstand the roughest of handling, but is mois- ture proof. It is heavily braced and insulated and is fitted with the extra wide and extra heavy webbed handle for ease in carrying. A feature of the Red Seal Sparkers—steel clad—is the construction of the top of the steel container. That part of the top where the handle is attached and through which the bind- ing posts protrude is raised, thereby preventing the possibility of water seeping through and causing a short circuit. The Red Seal Sparker is the dependable igni- tion battery noted for its pewer and ability to recuperate quickly after severe drain. To get the utmost in battery ignition for automo- biles, tractors, motor boats and all types of stationary gasoline engines, make sure your battery is a Red Seal Sparker—steel clad. A complete line of 4, 5 and 6 cell sizes is obtain- able at electrical, hardware and automotive supply dealers. Use Red Seal batteries for experimental work and for bells and buzzers or any other work requiring dry batteries. _SPARKER re ee: Sa RE Red Seal batteries are made by the Manhattan Electrical Supply Company, Inc., expert battery makers for over 30 years, and the oldest and largest distributors of radio products. Makers also of Manhattan Headsets and genuine Bakelite Variometers and Variocouplers. . Dependable dealers carry Red Seal and Manhattan products ANHATTAN ELECTRICAL SUPPLY CO, INC. Makers of the Famous Red Seal Dry Batteries, Radio Sparkers and Manhattan Radio Products New York Chicago St. Louis San Francisco Plants: Jersey City, N. J.; Ravenna, Ohio , Hy ! i | ; j

Page 90

104 piccommanied

writes a happy - United Y.M.C.A. Schools’ student,

formerly of Scranton, Pa., and now in the em- ploy of the United States Government. He was an office clerk, working long hours. He says “the light had dawned’ that he was tied down to routine work for all time unless he trained himself. So he decided to devote spare evening hours to our excellent correspondence course in accountancy. He earned a salary in- crease of 60% before completing his course and in a year qualified for United States Internal Revenue service (Pittsburgh Division) as audi- tor of income taxes, with a further substantial increase of salary and responsibility. The course he selected is just one of more than three hundred that we offer, all reasonably priced, all bringing the close personal service that is a feature of United Y. M. C. A. Schools instruction by mail. Do you want more power, more money, a broader field? Write us about your ambition and get our friendly counsel free. Soon you, too, can be throwing up your hat over the advance you have made. Some of our 300 Correspondence Courses Business Courses

Law Letter- Writing

Technical and Other Courses Insurance Courses Mathematica! Courses Agricultural Cour: Applied Psychology ban Mechanical Engineering ie Courses Own-Your-Home Building ie Plan Reading Civil Engineering Courses Plumbi: Drafting Courses Poultz ; Husbandry Electrical Courses gineering English Coursee Radio Tele, phy ry Management preening. Courses ‘oreign Languages Stract Foremanship High Schoo! E neering Use o ut the Bide Rule ustrating dvoven an en-eorvies Instruction 347 Madison Avenue New York City

V Dept. s-m POOP R OHHH EEHES EEE HEHEHE EEE EEE SESE ESE EE EEE Popular Science Monthly

THE HOME WORKSHOP

How to Remodel Old Furniture Profitably By Gladstone Califf S THERE an old table l in your attic that might be refinished, or a bureau of your grandmother that could be remodeled into a writing desk, or an old walnut breakfast table with a warped top that might be transformed into a dressing table? If so, why not undertake the work now, when the evenings are using the ends as they are and mortising longer rails at the front and back. The washstand drawer, if there was one, will probably serve for the dressing table. Perhaps you have a discarded bedstead of some kind; it offers many opportunities. I converted an old fashioned

long and your home work- shop is particularly inviting? You can do all sorts of mir- acles in the way of remodel- ing and refinishing old pieces, as I know from my own experience. Almost every family has old pieces of furniture that belong to the past and are cherished only ffor_ their associations. These possess little value from the view- point of a secondhand dealer, but often can be given con- siderable actual value by a little work with tools and brush.

walnut bed known as a Jenny Lind bed, into the card table illustrated. The table has a double top. The half that or- dinarily stands against the wall can be let down and the whole top revolved so that the hinged joint runs across the frame, and both halves are supported squarely and centrally over the frame. The top is square when opened to its full extent. The proper place for the pivot can be found by trial. The legs were made by saw- ing off the parts marked A, B, and C. Each pair of parts A and B was joined together ee Ye by t ¥ . wt 1%

Suppose you have an old a - walnut table with a good nut bed top and two drop leaves, as I had. You can do many things with it, and one is to make a dressing table. Pick out the side that has the best appearance and cut out openings for the drawers in the rail. Make the drawers to fit, being sure to get them square and true. This work is not difficult, especially if you are lucky enough to have a combination plane. The sides and bottom of the drawers can be made of soft wood, such as cypress. Drop Leaves Make Mirror Frames The mirror rest is a straight piece of wal- nut; the frames are material from the drop leaves, the corners being fastened with halved joints. The glass fits into rabbets cut in the back of the frames. The center frame is stationary and the two side ones are hinged to it with loose pin butt hinges. The glass is dropped into the rabbet, a piece of heavy paper is laid over it, and it is fastened in place with brads driven into the frame at an angle. A piece of wallboard is nailed to the RABBET FORGLASS back of each frame with round - top, the end rails strip of wood nailed side. with a dowel. Some work was made saved because the lower part of A was already mortised. The sides of the bed provided ma- terial for the sides and ends of the table. The leaves from an old table were used for the top. Another old table made the fern stand illustrated; in fact, it is simply the table without the being cut down to give the desired width. A narrow

on top of the rails provides a ledge for therim of the metal lining. This copper or galvanized iron lining can either be made at home or ordered from a tin shop. The attractiveness of the fern box is en- hanced if a bird cage is hung over it. If possible, make and finish the bird cage of material to match the table and support it from an arm screwed to the back of the stand. Hinge the door of the cage and pro- vide a small metal sand and gravel tray to slip into the cage through a slot at one An old fashioned cupboard of wal- nut lent itself readily to being remodeled into a china closet, al- though it could just as well have been made a most attractive book- case. This par- ticular cupboard brass upholstery nails or escutch- eon pins. The drawer pulls are wood to match the table, al- though commer- $s AT HOM a = an cial knobs fin- DETAIL - ished in dull bronze or other (Please write plainly.) MAKE MONEY

Old table adapted as fern stand OU ecanjearn from $1 to $2 an hour in your spare time Walnut table converted

writing show cards. Quickly and easily learned by = new simple ‘ ee method. No canvassin: solititing; we teach you how, guarantee you steady a home no matter where you live, and pay you cash eac hee ull particulars and Booklet Free. AMERICAN SHOW CARD SCHOOL 206 Ryrie Building Toronto, Can. or $100, $150 up. Lorr is BROS. an co. L-871 106 N. State St., Chicago,

finishes can be used, if preferred. Perhaps the table you have is a little larger or smaller; you can use your own judgment as to dimensions. If you run out of wood, you can find what you want at a lumber yard, except perhaps some of the finer hard woods, such as walnut, but even then the lumber dealer will get it for you or you can buy it by mail from one of the large firms specializing in lumber for man- ual training classes. An old washstand or a very small table can be converted into a dressing table by into dressing table was turned into a fine medicine chest. had tin panels in the sides and doors; these were replaced with wooden panels in the sides and with leaded glass in the doors. Another table provided the material for a piano bench. This is a simple matter and calls for the making of only two mortise and tenon joints. The legs are two pieces glued and nailed together, the heads of the nails being set and the holes filled with sawdust and glue. An old fashioned clock case In refinishing such pieces as these, the (Continued on page 106)

Page 91

hly — aS ee a ee ae ee ee ec ee Ss tem oO March, 1923 105 5 ee Te YANKEE'N®! uf) Ad gio Zz oi ud uJ x Zz six > «, Impossible’ jobs easy when you use these tools ; When you have to work where you “‘can’t”—when you want to save time and labor—you can solve your problem with “YANKEE?” Tools. ‘‘YANKEE”’ Ratchet Breast Drill No. 1555 has the “Yankee” DOUBLE Ratchet which keeps bit cutting continuously even if you can move crank only an inch either way. Fingertouch changes adjustment to Right- or Left- hand Ratchet. Plain Drill or gears locked. ‘Two speeds, changeable without stopping work. ‘““YANKEE”’ Ratchet Hand Drill No. 1530 is only 104% in. long; weighs only 20 ounces; slips into pocket—yet has same five ratchet adjustments as big “YANKEE” Drills. Drills up to 3/16 in. Magazine handle for bits. ‘“YANKEE”’ Ratchet Chain Drill No. 1500 does away with hand feeding—saves breakage of drill points. All you do is turn; automatic feed keeps pressure exactly right. eee “Saree” Sate ‘“YANKEE” Screw-drivers and Push Drills. Spiral —.. a. Screw-drivers: Regular, Nos. 30,31 and 35, and Quick Return, Plain Hand Drills Removable Base Nos. 130, 131 and 135 to work with one hand. Ratchet Screw-drivers drive screws like winding a watch: Nos. to and 11; also No. 15 with thumb turn. Plain Screw-drivers that won’t loosen in handles: No. go Standard, No. 95 Cabinet style; up to 30 in. blades. Dealers everywhere sell ‘‘Yankee’’ Tools Tool Book Mailed Free Illustrates and describes all the ingenious ‘‘YANKEE” Tools for doing ‘‘impossible’”’ jobs in drilling and tapping metal, boring in wood, and driving and drawing screw. Write for your copy today Push drills: No. 44 adjustable Tension saves drill points; No. 41 without tension. NORTH Bros. MEG. Co. Philadelphia, U.S. A. ~ YANKEE TOOLS Qnake Beller INechanics

Page 92

Span MAE MIND ETE A Rp EI 2 a pee ee ee eee sti sins actow Mia Ya > Soy ated for aa. Serta 106 _ The letter that raised my salary I certainly was surprised when Mr. Jordan called me into his private office. “I want to congratulate you, young man,” he said, “on the splendid record you are making with the International Correspondence Schools. They have been sending me reports of your progress and this last letter is particularly fine. “I want you to know that the firm never overlooks a man who cares enough about his work to study it in spare time. Beginning to-morrow, you are to take over Jim Hanna’s position at an increase of $50 a month. I wish we had more men like you.” THE HOME WORKSHOP Remodeling Old Furniture (Continued from page 104) first step is to remove the old finish and sandpaper the surface smooth. Any pieces of new wood should be scraped with a cabinet scraper before sanding: Where staining is necessary, a good acid or water stain can be used, but before applying it, a sponge dipped in hot water is rubbed over the wood to raise the grain. The stain is followed by a thin coat of shellac, which, when dry, is sandpapered The bookcase with leaded lass doors, shown at the left, was made from a dis- carded cupboard. The iano bench below, which s another reclaimed piece, has a music com- partment beneath the top with fine and well worn sandpaper. The Popular Science Monthly \ \ ~~ S X — at your finger endS 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 subject covered so you can understand it. Eusy to study and apply. A com- plete, practical working course, in 10 volum es. Books are pocket size; flexible covers.’ Order a set to-day to look over. HAWKINS GUIDES 3500 PAGES 1 A VOLUME 4700 PICTURES 1 A MONTH These books tell you all about — Magnetism — Induction — Experiments — Dynamos — Electric Machinery — Motors — Armatures — Armature Windings — Installing of Dynamos — Electrical Instru- ment Testing—Practical Management of Dynamos and Motors -Distribution Systems- oan. heron bapa 5 | one rinciple: Mare tha ing goo pla .y Th ° : : —Sign Flashers—Storage Batteries— ples of Alter- sanding smooths the grain previously nating Currents and Alternators—Alternating Current th Employers in every line of business | raised by application of water. Wood filler | Mating Current ‘Systeme Cireuit: Breekcrs~ Measuring ha Who really want to get ahead in the | i8 next applied with a brush and when it | Instruments“Switch Boards Wiring, Power Stations world and are willing to prove it by | begins to lose its gloss, wiped off across the Lighting—Railways. Also many Modern Practical Appli- m training themselves to do some one thing i ll 5 hard toh Th . cations of Electricity and Ready Reference Index. well. Prove that you are that kind of grain. Allow it to harden overnight. e e SHIPPED TO You FREE tu @ man! filler should be the same color as the stain; = = oon th F rs ae = * otacent to pay until you see the books. No obligation ee Ltt Pet anak Gd eens tae | Ot, BAtte wet ataieng, tobuy unless you aresatisfied. Send Coupon now—tda he ’ ee —and ge 1s grea e iprar see 18 not wor goupon., yt ng hag pen aed of what gg ces ee. $100 to you—pay $1.00 a month forten months or returnit. as . co. Bs ! ne or two W Se ee S THEO. AUDEL & CO. INTERNATIONAL CORRESPONDENCE SCHOOLS shellac are then ap 72 Fifth Ave., N.Y.” st Box 7630-C, Seranton, Penna. plied, and each rubbed Daaties Mami Sotoee Without cost of obligation on my part, please tell me 7 : = hs how I can qualify tor the position Yor'in the subject. before with sandpaper. 2 a die a ene * 7. | which I have marked an X: The next step is to agree to send you $1 within seven days ond BUSINESS TRAINING DEPARTMENT apply three coats of a to further mail you $1 each month until paid. OBusiness Management OSalesmanship . CIndustrial Management O cecpenag pd good grade of varnish. 7 Hrafie Management korean Trade | This must be done in a = orton Busi L Stenography and Typing * mp! Banking and Banking Law (J Business English warm room, free from fn ib tedineed = tii . {jAccountancy (including C.P.A.) ( Civil Service dust. The last coat is itchen cloc a (Nicholson Cost Accounting (Railway Mail Clerk a A made-into a Reference _ P.S., MARCH '23 [Bookkeeping is eee ence rubbed with pumice medicine cabinet d Private Secretary gh School Subjects ° HBusiness Spanish ()French [)lilustrating stone and water, rot- | in TECHNICAL AND INDUSTRIAL DEPARTMENT tenstone and water, and finally rottenstone a 5 a Architect ; ; j j Llectrical Engineering A arch a and oil, for a polished finish, and simply Eas to Learn a Mechanical Engineer [j Contractor and Builder | rybbed with pumice stone and water for a . V Mechanical Draftsman |} Architectural Draftsman Es ° t Machine Shop Practice S psmmer adh 5 sou ll dull finish. : ¢ ) 4) { H m Haas Engine Operating Chenstry C) Pharmacy A variation in the method of finishing is ar nin a 0 e 2 Civil Engineer mobile Wor' * Surveying a Airplane Engines to pie! several coats of a — t Metallurgy griculture an oultry Steam Engineering () Radio (2 Mathematics out eac . coat, and finish witl two coats _ Earn $60 to $200 wax, polishing them with a silk cloth. This » Maite iu Cute eo vesstcckehsatnecanpuivepiverseessvs sabpoppooisouen Seameenot makes a fine finish for walnut and has the FE - | EES Aare LC RTS Te from time to time. This is the finish used Profession Ae for the dressing table. iacend cet oes ae Persons residing in Canada should send this coupon to the they been in such big demand! International Correspondence Schools Canadian, Limited, Successful cartoonists now earn Montreal, Canada. $3.000 to yond “r~ a mene. ou can learn to raw these cartoons that SELL. M f Furniture Features for April our students earn big money even while learning! Th Bi li h B aaa _ the exceptionally helpful Easy Home- e Biggest Little Lathe Built furniture articles in the April | | ¢ soi tudy Method é Home Workshop will be one on how y oe : ' THE p 5 P Prepared by one of America’s MONARCH to build a grandfather’s clock, with foremost cartoonists, this course e re i teaches you to originate and Junior designs for clocks ranging m value saad ees ey! yet all your work receives 9” Engi from $15 to $500. through the mail the individual H€lp and criticism. of gine 5 c prominent cartoon experts. Many successful cartoonists Lathe Others will describe the construc- taught by this method. . 214 ft. Bed tion of an inexpensive flat top desk, & ad £ F $225 a girl’s cabinet and writing desk, and er or ree Book Here is a ence small engine lathe built with a Colonial writing desk. rn Mig ll ee Fee syed thy Bosom Ry ‘ the same quality construction that hag made . qn - Our newly prepared Free Book i d with valuable MONARCH Lathes standard the wor over. Unusual hints on finishing will be ievanuhines cheat this work. and ounieias fully this casy Guaranteed to do any small work any other lathe found in “ Secrets of Making Realis- home-study method. Mail post card or letter for it will “" — it a 1/1000 of an inch accu- tin *hatinia! Peieae” TODAY! racy. It will fitin any shop or home work room. urniture. Easy to learn to operate: This d k sila a WASHINGTON SCHOOL OF CARTOONING . is describes in detail the little M ildi i WRITE for Free catalog of : . 1123 Marden Building Washington, D.C. MONARCH Lathes, which known tricks by which the home are built up to 30" swing. worker can duplicate the antique fur- e e THE MONARCH MACHINE TOOL CO. niture finishes now so popular. m In rizes 401 Oak Street , SYDNEY, Ohio See page 6 in front of book for full details

Page 93

fl wee — eo | oe y March, 1928 THE HOME WORKSHOP Painting Kit Keeps Materials Handy for Odd Jobs O MAKE easier the innumerable paint- ing, enameling, and varnishing jobs that constantly arise in every home, a paint- ing kit can be made from any stout box of good size. It should have two hanging plates, so that it can be hung on the wall in the cellar, garage, or workshop, and a handle for carrying it from place to place. The interior is fitted with small compart- ments for holding cans of paint, putty, wax, turpentine, oil, and the like, and hooks for the brushes, scraper, putty knife, tack hammer, glass cutter, and other tools. This assures all the material being available when needed. The box also serves as a step in the absence of a ladder.—G. A. Simple Adjustment Improves Homemade Loudspeaker Rr fans who use the Baldwin type C telephone in connection with a horn as a loudspeaker may have felt the need, as did the writer, for some method of adjust- ing the diaphragm so that the modulation and volume of tone can be regulated. To accomplish this the device illustrated, which cost about $1, has proved satisfac- tory. Speaking and singing come in clearly and naturally and band music has a good tonal quality that can be made low and mellow or loud and brilliant, as de- SMALL PIECE oF ” sired, by a slight BRASS ROD nina turn of the adjust- me oe ing screw. NUT SOLDERED OVER HOLE The first step _ 'N CLAMP is to bore a \4-in. hole in the rubber casing, as shown, to relieve the air cushion behind the diaphragm. A strip of %-in. brass 14% in. wide is bent to form a clamp and has a nut soldered over a hole in the center to take a bolt with a wingnut. A piece of brass rod or a nail is soldered to the bolthead as a handle. This clamp is used to hold against the telephone one of the rubber caps sold by radio dealers for connecting phones with a horn or phonograph. The threads on the inside of the cap should be removed so that it will fit easily over the phone. A length of small rubber tubing should be obtained at a drugstore to serve as a gasket between the cap and the phone when assembling the attachment. Adjustments are made by in- creasing or decreasing the pressure of the clamp.—JOHN A. MAHON. BALDWIN PHONE §} a'orass. iy WIDE PHONOGRAPH | ATTACHMENT | RUBBER TUBING | + Her y JF gnmMmo 107 The Bell System's transcontinental telephone line crossing Nevada Highways Necessity made the United States a nation of pioneers. Development came to us only by conquering the wilderness. For a hundred and fifty years we have been clearing farms and rearing communities where desolation was—bridg- ing rivers and making roads —reaching out, step by step, to civilize three million square miles of country. One of the results has been the scattering of families in many places— the separation of parents and children, of brother and brother, by great distances. To-day, millions of us live and make our success in places far from those where we were born, and even those of us who have remained in one place have relatives and friends who are scattered in other parts. - Again, business and in- toward Better Service of Speech dustry have done what fami- lies have done—they have spread to many places and made connections in still other places. Obviously, this has pro- moted a national community of every-day interest which characterizes no other nation in the world. It has given the people of the whole country the same kind, if not the same degree, of interest in one an- other as the people of a single city have. It has made neces- sary facilities of national com- munication which keep us in touch with the whole coun- try and not just our own part of it. The only telephone service which can fully serve the needs of the nation is one which brings all of the people within sound of one another's voices. : “BELL SYSTEM” AMERICAN TELEPHONE AND TELEGRAPH COMPANY AND ASSOCIATED COMPANIES One Policy, One System, Universal Service, and all directed $300 Profit Barer charging Start your own moneymaking battery charging busi- ness NOW. No experience needed to make big y profits with HB 8-hour Battery Charging. Universal demand, low operating cost. on easy terms more Months to than carried by your caecenvediie. tne sue gemma tier Ne ¢ . Daymen' in; hour charmer on long trial with moneyback si HOBART 2232 atioi a income. from 100 to 500%. Dept. 43 “HOW | BEAT THEGAME’ The Inspiring Story of how one poorly paid garage mechanic won success, his own business and a big Tells how you can increase your salary Send for it today FREE. Ambu Engineering Institute 2632 Prairie Ave., Chicago, til. What You Can Do With this Boice Bench Saw Saws 7"' dia. cut 2%" stock. Dado head 5" dia. cuts grooves 11%" deep x &"' wide, maximum. Screw adjustment elevates table for exact depth of cut. - Machine will also cut brass, bakelite, tubing, rods, carbon, and many similar materials. ¥ h. p. ball-bearing. = on a positive Money-Back Boice-Built Bench Saw Model 140, illustrated here. provides a convenient, speedy, and eco- nomical way of doing hundreds of jobs requiring power and precision. Does cross-cutting, ripping, mitering, and groov- ing, with ease and accuracy. Special attachments enable ma- chine to do grinding, sanding, drilling and dadoing. Write today for circular and Bench Saw, 4” Josnter, 14" Motor uafantee. ices on this machine, and also on Boice Junior nch Band Saw, Motors and larger bench saw W.B.&J.E.Boice, '.i3,' Toledo, Ohio copper,

Page 94

POLE A IETS SARIN I ITEM NE TERA mR atin eaetangs EN para bata oy we, uals pe ata snitlap ict ae alee Pores eed eee eo eae eT Se elas a HORDE EATER ONE ETRE EIN TT I EIT HEROS IAT SIE ara 8 he Lisle i 03 Bs ore nee Sea “ae eee es ——Never ! Frosty weather and roving snowdrifts just add a new zest to the all-year sport of motorcycling. None of the automobile’s winter troubles bother the Harley - Davidson rider. His husky mount gives him full mastery over all road conditions, winter and summer — the same eager power, the same ‘tremendous’ burst of speed, the same rushing get-away. And the economy! No other gasoline vehicle can approach it—50 miles for a dollar, counting gas, oil, tires and all. Your local dealer has the 1923 Harley- Davidson models, with their 10 im- provements and reduced prices. Look 'em over! Or, write us for _ free literature. 2. 0. oe os Harley-Davidson Wor lJ's Champion Motorcycle Boney: making sales op portunities in open territory. Write Desk A-2 Have You an Invention? If he WORLD R 1 alfn’s te ort saan vo RogREss wil show you how to PROTECT Thi the p interests of Inventors. It 8 magazine is devoted recenee 9 opens oe mysteries of “elence and Invention to the student of every- day problems. Sample Copy Free. Also send for fr: “*What to Invent’’ containing: EUGGEENONS TO DIVENTORS from prominent inventors Needed. We invite manufacturers and A to KA... us regarding i any cores or patents the may want. We will publish such inquiries without charge. Address . World Progress Pub. Co. Inc., Room 203 Victor Blig. .» Washington, D.C. One years *s subscription $1.00 freer Get Toll aformetion about the. Deski951-S $25.00 in Prizes THE HOME WORKSHOP Tools for the Home Workshop (Continued from page 77) be held firmly and securély on a solid bed. For very fine work, the cap iron should be set very close to the edge of the cutting iron. For coarse work, the cap iron can be set back as far as 4 in. The bevel of plane | cutters is at an angle of 25 degrees, as at B, Fig. 1, page 77. Approximately speaking, the bevel is twice as long as the cutter is thick. If the bevel is too short, the plane will not cut well, and if it is too long, the plane will jump and chatter. In sharpening a cutter on the oilstone, avoid the common fault of making a short bevel, as at C, Fig. 1. Keep your hand down when rubbing on the stone to make a long, bevel, thus obtaining a keen cutting edge. It goes almost without saying that in sharpening a smooth plane, fore plane, or jointer, only the corners of the iron are slightly rounded, as at E, Fig. 1, whereas the iron of a jack plane for rough work may have aslight curve, as at D, Fig. 1. Rabbet planes, like chisels, are perfectly square with sharp corners, as at F. The pitch or angle of the iron in the plane varies according to the work that is to be done, and ranges all the way from about 80 degrees, as in tooth planes used for scraping surfaces in preparation for laying veneers, to 12 degrees in the case of some of the modern low angle block planes. In one case the action approaches scraping and in the other, shaving. For fine work, especially dressing cross grained or gnarled surfaces of hard wood, and for use with a shooting board in planing miters, a plane with a low angle cutter is useful. The woodworker has, indeed, a wide range of choice in selecting fine planes and can get many varieties for special work, such as edge trimming planes, bullnose planes, cabinetmaker’s edge planes, not to speak of universal plow and matching planes and molding planes. Tricks in Sharpening Saws Sharpening saws involves no more diffi- culty than sharpening planes when once the principles have been learned. A new saw is properly set and sharpened, so that all the woodworker has to do is to preserve the teeth in the same shape and condition as when new, so far as possible. never let a saw get into bad shape before re- sharpening. The teeth should first be “jointed” or time the saw is filed, but should be done this is sometimes done before top jointing. Various saw sets can be obtained for this purpose. The points are bent alternately right and left, as in the original setting, and it is important not to set the teeth too far into the saw. In other words, give the teeth as little set as will serve. Fine saws, such as panel, dovetail, and tenon saws, sometimes are not set at all, the taper of the blade giving sufficient clearance. Begin at one end of the saw and set every other tooth. Then reverse the saw and set the remaining teeth. If the setting has been done unevenly, file the teeth edges on the side with a mill file. The files to be used for sharpening are (Continued on page 110) See page 6 in front of book for full details Therefore, | made even in length by running over thema | flat file held by hand or in & saw jointer, as _ | at A, Fig. 2. This is not necessary every | when the teeth have become noticeably | uneven. Next, the teeth are set, although | Popular Science Monthly LONG-DISTANCE Regenerative RADIO Receiving Set Built nd Tri Ne | Radio Electric Co. (Licensed under Patent No. 1,113,149 and pending letters Patent No. 807,388.) The . “Sensitone’’ brings in concerts, bands, lectures, market, crop and weather reports, sacred services and sermons, bed- time stories for children—all the wonderful programs of your pick of all the 500 broad- casting stations in the U. S. and Canada. ‘*‘Sensitone’’ Set is complete—includ- ing batteries, tubes, head-phone, antenna, wiring - connections — everything you need, ready to install, is equal to sets now sold at $150.00 to $175.00, yet our price is only $95.00. Set is shipped on receipt of the first $15.00 pay- ment. You are dealing with a responsible, old-es- tablished House. Ask any banker or business man to look up our rating in Dun or Bradstreet Reports. Only a limited number of ‘‘Sensitone” sets will be sold on this easy-pay plan. Fill out coupon and — check or money order for $15.00. Circular free. HAROLD R. WAKEM & CO. 836 Ww. W. Washington Se., Chicago, ail Harald R. Wakem & Co 6 W. Washington St. .» Chicago, Ill. ethane you will find $15.00 as first yment, upon receipt of which you will send me your ee ‘gaa tone Radio Receiving Set, as described above. I agree to send you $10.00 every thirty days thereafter, until the full purchase price is paid. his set is to remain the property of _—— R. Wakem & Co., until paymente are complet Ce ea a a aa a ae In the spaces below give the names of two references, banks or business houses preferred. BaNN PURINE NEAR ONIN oh 0 535 ip Sop aio 0 5 Sis Kb 00 le OO bc ielovars Pierre athe RO 55 5 54 9 ois ns ids 0s os oie aS 0/5. ae | BY DOING Every phase of all branches of * 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

Page 95

thly March, 1923 109 Kellogg Radio Equipment for Better Results d- Kellogg radio equipment for the radio fan has proved the best, because of its durability and . accurateness. Being easily mounted and simple to operate makes it unusually efficient and 4 brings the best results with the least effort. 4 For every dealer, Kellogg apparatus is the easiest to handle, because of its reliability, and because it is manu- a factured by the Kellogg Switchboard & Supply Company, who have had over twenty-five years’ experience in ts manufacturing high grade telephone-equipment. The Kellogg dealer has this sign in his window: ur 66 : a @ 399 y- : We Guarantee Kellogg Radio Equipment et be HEAD SETS VARIABLE CONDENSERS The value of extremely Decremeter type 11, 23, and light and very small head 43 plate with and without ver- sets in Radio Receiving is nier. Standard capacities. . most evident when using With this variable condenser Kellogg head receivers, the dial scale can be correctly cali- - which, however, have proved as brated. The amount of increase - sensitive and thoroughly effi- or decrease of the plate surface vari- “ — as they are light in weight ation is always constant. te and small in size. The band, , a , a nth too, is pl es eiaiel cena » No. 601 11 plate with 5 plate Vernier. Knob—4 Dial the simple receiver holders , —_ List each, $6.75 . \\ which are held in place on the No. 602 11 plate without Vernier. Less Knob and Dial ” No. 694 lower part of the head band by No. 60 i — a = each, 4.50 a 0 the spring tension of the metal, No. 603 23 plate with 5 plate Vernier. Knob— 9 a tant t i P a ; hace | = pi By ng He, oe as to place the receivers over No. 604 23 plate without Vernier. Less Knob and ps ah oe “ a = ee i — 5 soccer eererecs —_, mae No. 605 43 plate with 5 plate Vernier. Knob—4’’ o— S — NO. ea RRERINRES 6155406" ste: cils/'s19-4. 2. CREM ol ist each, 58. No. 74A Head Set 1000 ohms................-each, 5.00 No. 606 43 plate without Vernier. Less Knob and fe — ist each, 6. DIALS RHEOSTATS VARIOMETERS The Kellogg rheostat is sim- = ple in design, having but one * movable part. The resistance wire is carried on a rotor of high grade insulating material and the contact arms are so Y hiageagg a slight movement ey ee et ee forced construction. 5/16” shaft knob is th "si All Bakelite moulded variometer. : ; ee it nob is the same type and size as - ce with bushings for 4’ and 3/16 the Kellogg dial. Two rotor and three stator terminals. d shafts included. Standard wound. For panel or base —_ No. 501 3” Dial......... $1.00 No. 501 No. 501 Rheostat............. $1.50 mounting. d No. 502 4” Dial....... 1.25 No. 501 Variometer......-- $8.00 of All Kellogg Radio equipment is of the same high standard and is guaranteed by Kellogg——-USE, IS THE TEST log K KELLOGG SWITCHBOARD & SUPPLY CO., CHICAGO L

Page 96

5 ; i 1 ama ee ee FP ain a 7

toner tere Fa ae 110 Popular Science Monthly

Eddie Elkins of New York, (top) and Max Fisher of Los Angeles, <bottom) are among the popular orchestra directors who endorse Conn instruments. Can

cA Profi

table Pleasure Brie instruments place a world of pleasure, unnumbered opportunities for profit, at your command. For two-score years they have been recognized supreme by the world's greatest artists in concert bands, symphony, opera and popular orchestras. Exclusive features make Conins easier to play. The most celebrated artists, including the great Sousa, use and endorse them because Conns are more perfect in tune and tone, have more reliable action, are easier to blow, more perfectly balanced, artistically designed and finished. More Conn saxophones are sold than any other make in the world. Simplified key system, patented tuning device, perfect scale, and many other ex- clusive improvements make. them “the choice of the great “jazz” kings. You want the best; be sure you get a Conn. FREE TRIAL, EASY PAYMENTS. Send now for information on how to get any Conn instru- ment for trial in your home. Connistheonly manu- facturer of the complete instrumentation of a band. Highest Honors at World Expositions. All Exclusive Conn Features at No Greater Cost. Dealers and agents throughout the country. Factory branches in many large cities. C. G. CONN, Ltd. 332 Conn Bldg. Elkhart, Ind.

WORLD'S LARGEST MANUFACTURERS OF HIGH GRADE BAND AND ORCHESTRA INSTRUMENTS

CULTIVATE YOUR MUSICAL BUMP)

THE HOME WORKSHOP

Tools for the Home Workshop (Continued from page 108) generally a 7-in. slim taper file for a 5, 6, or 7 pt. saw, a 6-in. slim taper file for a 8 or 9 pt. saw, and a 5-in. slim taper file for a 10, 11, or 12 pt. saw. Clamp the saw in a saw vise with the point or toe at the left and, beginning at the left, file alternate teeth the entire length of the blade. Place the file well into the : gullet at about the angle at which the teeth originally were filed, and see that the tooth | that is set toward the other side of the saw

' is on the right side of the file. The position of the file on the teeth of a crosscut and rip saw is shown at B and C, Fig. 2. The file can be either held level, as at F, or tilted up, as at G. The latter angle is more difficult to maintain unless an adjustable vise is used, in which case the whole saw can be tilted so that the file itself may still be held level. The difference in the resulting shape of the teeth is indicated at D and E. Ordinarily the point of the file is pointed a trifle toward the point of the saw, although a ripsaw for general work can be filed straight across. The exact angle at which the file should point back is quickly learned by experience and varies with the sort of work that is to be done. Some mechanics, however, will tell you that the | file should point toward the handle and, as a matter of fact, opinions differ, but if the file is pointed toward the handle, the point of the file must be tilted up as shown in the oblique position at G. When the saw is reversed to file from the other side, the same angles are maintained, only now the teeth that are set away are on the left of the file. The final step (H) is to pass a hard oilstone over the sides of the teeth lightly once or twice to remove any wire edges pro- | duced in filing. Protecting Tools from Rust The best protection for tools that I have found is to pass a rag saturated with good lubricating oil cver all the saws, chisels, planes, and bits now and then. If this is done over both wood and steel every two or three weeks, the tools will look almost like new after years of service. If the steel should get damp with rain or otherwise, a piece of very fine sandpaper or fine pumice stone powder should be rubbed on with some oil. When tools are to be put away for some time, it is advisable to mix a little vaseline with the oil, to give it a greater body, and cover the steel parts liberally. If dampproof drawers or closets are not available, a carpenter’s “‘shoulder box’”’ is a good substitute. By getting into the habit of slipping the tools into their individual racks or places every time one gets through using them, and if the oil rubs are not omitted, the tools can be kept in good shape even in a damp place. Boxes ar- ranged to receive complete Working sets of tools are now made at such reasonable prices that even mechanics prefer to buy rather than to make them. Bits, fine chisels, and gouges are done up in cloth rolls with pockets for each tool. . These usually come with complete sets of tools, but they can easily be made at home. When you strike a nail with a bit, re- store the edge with an auger bit file or a fine warding file. Keep to the angle in which the bit was formed and never file on the | outside. Do not file any more than is ab- } | (Continued on page 112)

Ma

Page 97

onthly ——_..., — 1p }, or t —- me ~~ em we SN WS = § om er March, 1923 Ill You can now obtain Condensite Celoron Radio Panels cut in standard sizes You can now get radio panels already cut to a size to fit your needs. For your convenience we are making Condensite Celoron Radio Panels in seven standard sizes. No longer will you have to wait and pay extra cost for hav- ing your panel cut to order. These sizes have been so de- signed asto meet practically every need of the set-builder Each panel comes trimmed and wrap- ped separately in glassine paper to protect the surface. They are all ready for immediate use. On every one are full instructions for working and finishing. What Condensite Celoron is Condensite Celoron is a lam- inated phenolic condensation product used by many of the leading manufacturers of radio equipment. It has high insula- tion resistance, high dielectric strength, low dielectric losses and is easily worked. Because Celo- ron has these qualities it has re- ceived the approval of the U. S. Navy Department. Bureau of Engineering and the U. S. Signal Corps. You can obtain any of these seven standard sizes: 1. 6x 7x 4. 7x18x3/16 2. 7x 9x4 5. 9x14x3/16 3. 7x12xlk 6. 7x21x3/16 7. 12x14x3/16 Select the size you need for yourset. If your radiodealer has not yet stocked them, ask him to order for you. Or write direct to us, designating by number the size you want. We can make prompt shipment. To radio dealers: Write for special dealers’ price list showing standard assortments Diamond State Fibre Company BRIDGEPORT (near Philadelphia) PENNSYLVANIA BRANCH FACTORIES AND WAREHOUSES BOSTON CHICAGO SAN FRANCISCO Offices in Principal Cities In Canada: Diamond State Fibre Company of Canada, Limited, Toronto. | j 4 hy | CELORON STANDARD RADIO PANEL — wre de tan ale

Page 98

bonieaa Spe ah: Gon Behe SoBe ane erate ren ERI Ratio 25 el f | KE iF Ve ey SE AR ANI RBIS A RTT OAR RUR OAT OTE 55 Sie ts a. RE IY De te se pili: BINT Sih re Pe 112 '_¥Free Railroad Fare t ~~ ; “a Student Winding a Stator To the Great Shops of Coyne We pay your railroad fare to Chicago—the Electrical Center of the World—from any place in the United States. Grasp the opportunity to see the country at our expense. Come to Coyne—learn electricity in 342 months. Geta complete training so you can make big money as Power Plant Operator, Superintendent, Telephone man, Construction worker, auto, truck or tractor electrician, battery man, radio expert, or you can go into business for your- self as electrical contractor, dealer, auto igni- tion or battery — and make from $3,000 to $20,000 a year. undreds of our graduates today are making big money and you can dothe same if you grasp this opportunity — act now. Learn Electricity In 3% Month No books or useless theory. You are trained on $100,000 worth of electrical eae. Everything from door bellsto powerplants. You work onmotors, generators, house-wiring, autos, batteries, radio, switch-boards, power plants—everything to make you an expert ready ‘to — right into a position paying from $45 to $100 a week. Radio Course FREE We include the following free with the regular course; o A complete course in auto, truck and tractor elec- city and sto. batteries, Greatest outlay of auto, electrical and battery equipment in the country. (2) Course in Radio—the marvel of the age. Con- structing, installing and operating. You can build you own wireless telephone set. (8) Alife scholarship in the Coyne school. You can stay as long as you wish and return for further training at any time in the future. Earn While You Learn We help students to secure jobs to earn a good part of their expense while studying. - Send Coupon Now Don’t delay a minute—send that coupon in right now for our big free catalog and full particulars of Free Railroad Fare offer. Act now! B. W. COOKE, President Coyne Trade and Engineering School Dept.1363. 1300-1310 W. Harrison St., CHICAGO Popular Science Monthly B. W. Cooke, Pres, Coyne Trade and Engineering School, Dept, 1363 , 1300-1310 W. Harrison St., Chicago, Ll, Dear Sir: Please send me free your big catalog and full particulars of your special offer of e Railroad Fare and two extra courses. THE HOME WORKSHOP Tools for the Home Workshop (Continued from page 110) solutely necessary or the bit will soon be useless. I have often been surprised that amateur woodworkers do not make more use of hand screws. They can be put to innu- merable uses and serve to increase one’s thumbs and _ fingers. At least two good iron woodworker’s clamps will be found invalu- able at times for hold- ing material when working it or gluing it up, especially if any furniture making is done in the home workshop. The Tools I Use in My Home Workshop By Joe V. Romig Y WORKSHOP comes second only to my family in my affections. It is a dream shop—a boy’s dream made possible through a man’s work and development. My tools are chosen particularly for metal work, and with a few additional carpenter tools, they have served in the construction of many pieces of experimental and model work. My vise (I could write a book about a vise alone) has 4-in. jaws that open 5 in., and a swivel base, which allows the work to be held in the most convenient position for filing and chipping. I take care of this most important tool, never pinching red hot iron between the jaws, or using a sledge hammer on it when bending rods or flats. I would Pa a) WP) aousmae viSE HACK SAW AND FRAME The style of vise, bench drill and hacksaw used by Mr. Romig not permit my best friend to straighten a piece of steel on the flat°of the slide. In buying a vise, I should always give prefer- ence to one with set-in steel jaws; this adds to the cost, but makes it possible to put in new jaws when the old play out. - My bench drill I chose with a view of practicability, and it holds drills from 0 to 3g in. It is equipped with drill pad and chuck. In order to lighten the strains of drilling large holes, I always drill a small lead hole first. I keep the tool well oiled and never try to make a punch press out of it by using a dull drill. My hammers are many, three machinist ball peins, 114, 114, and 1 lb., a pattern maker’s hammer of medium size, a 2-lb. sledge hammer, and an assortment of small ball and straight pein hammers, from a few ounces up to half a pound. Included in my lot of hammers I must mention two wooden mauls, as well as a brass and a lead ham- (Continued on page 113) LEARN CARTOONING it’s Easy with Landon Picture Charts If you like to draw— develop your ability and become a successful car. toonist. Get the same instruction— the same help that has developed so many of the succcessful cartoonists of today. Hundreds of nationally known cartoonists —youn fellows such as Branner the Chicago Tribune; Blos- ser, who draws ‘Freckles and His Friends’’; Gene Byrnes, creator of ‘‘Reg’lar Fellers’’; Dorman Smith of the N. E. A. Service; Thiele of Sioux City Tribune, and scores of others equally famous developed their ability, at home, through the famous LANDON PICTURE CHART METHOD Leading educators every- where pronounce Landon Pic- am, ture Charts as the greatest ens achievement in the teaching Ry of drawing. No other method —=\N of teaching gives you such a thorough understanding of the fundamentals of drawing —none develops originality so rapidly. Why Landon Course Is Superior ] Landon students secure * best cartooning positions. Picture Chart Method is *used exclusively by the Landon School. - This course teaches ’ ORIGINAL drawing only. No copy work. 4 Individual attention and criticism of students’ work. Specialized instruction eon originating cartoon ideas. Price within reach of all. ’ Easy payments arranged. Write today for sample Landon Picture Chart, long list of successful Landon students and full information showing possibilities for you. Please state your age. The Landon School 7051 National Bidg. Cleveland, Ohia Easy to Play Easy to Pay Clyde C. Doerr Director Clyde Doerr 4 and His Orchestra, makers of Victor True-Tone § Easiest of all wind instru- ments to play and one of the ‘ ost beautiful. You can learn the scale in an hour’s prace tice and play —— music ina 1% few weeks. You can take your Xk \ Diace in a band within 90 days, if hi) you desire. Unrivalled for home en nment, church, lodge or schoo, In big demand foF ore chestra dance “> ~ 4 ou ma: er Free Trial jocch instr j ment without paying one cent inadvance, Py and try it six days in _ your own home, with- f=" out obligation. If perfectly satisfied, pay for it on easy payments to suit your convenience. 75% of all popular phonograph records are played with Buescher instrue ments. Ask for pictures of the my Saker. A Saxophone Book Free gipremacy, string in- struments are almost entirely di —g by Saxophones in all nationally popular orchestras. Our Free Saxophone Book tells which Saxophone takes violin, cello and bass parts and many other things you would like to know. Ask for your copy. Mention the instrument interested in and & come plete catalog will be mailed free. 5 BUESCHER BAND INSTRUMENT CO. Makers of Everything in Band and Orch i) 3159 Buescher Block ELKHART, INDIANA Sax Invented the Saxophone Buescher Perfected It Saxophone me he thi ke as TO = - 65 rh ee ae ae a Se

Page 99

uthly rts and Car- ame 1me ssful ally in, lose cles ene ‘lar iele am ally leir igh yerys Pic- atest hing thod ch a r of wing ality

March, 1923

THE HOME WORKSHOP The Tools I Use (Continued from page 112) mer. It pays always to use a proper weight hammer for the work in hand. Ifa hammer head should prove too hard and chip off, I throw it away, as it is a dangerous tool to keep, and even if softened, it is already dis- figured by the chipped face. To get the best results out of a hammer, it must be fitted with a proper handle. Many hammers are bought with handles that remind me only of a stick of wood. By shaving a handle down to a thin section be- low the head, a snappier action is secured. To preserve the wood, I always give the handles several coats of shellac. Never use the hammer handle to bump or pound metal parts, as this will often cause the handle to crack or split; use a maul instead. My set of chisels contains all shapes and sizes, from 1-16-in. cape to 144-in. straight cold chisels. Many of them I forge out of octagon chisel steel, and temper according to the use I intend to put them to. If I break off a corner of the cutting edge, I always throw the broken chisel into the redressing box, and when enough accumu- late, I dress them all at one time. My files, of which I have almost all of the ordinary shapes and sizes, are kept accord- ing to size in a partitioned tray. The larger sizes are kept on the bench, as they are used | the most. Each file has its own handle, and | is never used without it. I clean my files _ with a wire brush and soft pine wood wipers, and never pound them on metal.

Micrometers and Measuring Tools My measuring tools consist of a 2-, 3-, and 6-in. rule, also a 12-in.combination set, the square and bevel protractors which have hardened and ground faces. A 50-ft. steel tape line, of known and guaranteed accuracy, is used for long measurements. My micrometers are of 1-, 2-, and 3-in. sizes, and a set of 2- to 8-in. inside microm- eters are used on internal work. A set of 3- and 6-in. dividers, together with a metal beam trammel set, serve for my layout work. I prefer spring calipers to the solid type, and I have them in 3-, 6-, and 12-in. sizes. One of the handiest tools is the drill gage for measuring drills and wire rods. This tool also converts the drill size into thou- sandths of aninch. All small tools, such as screw and thickness gages, center punches, surface and depth gages, scrapers, and the like, are kept in a felt-lined tool box. Oilstones of three different grits are kept in covered cases, to prevent dust from clog- ging their surfaces. My taps and dies are kept in three boxes; the fine threads have a die of 34-in. diam- eter, and the larger sets cut from 3% to 4 and 14 to 14 in. threads respectively. These sets have loose dies that can be replaced when worn out. I always try to keep at least two taps of each size on hand, so as to have one in reserve in case of breakage. My oil can is a close companion to all my thread- cutting tools, as oil makes for better threads and saves the taps and dies. My hacksaw frames, of which I have two, take blades from 6 in. in length up to 12 in. The blades are chosen for the work in hand, and for general all around use, I prefer a medium fine toothed blade. For cutting brass bushings and iron pipe and tubes, I always use a fine tooth saw. Oil is good to (Continued on page 114)

113 Auto Mechanic Makes’5200

Net Profit 1° Year Unlimited Opportunities for Auto Mechanics Here’s an opportunity to go into business for yourself. Greer men are making good money—they get the pick of waiting positions and are successful. You have the same chance to succeed. Greer training will fit you in a few short weeks to take a position or start a. business of your own, paying good money right from the start. advert eo yeat Bon00l: oss owe 8 WE PAY YOUR RAILROAD FARE 13

ce OS ee : é d §x0 De BODIE port ess mired Ne, This special offer is made to fill the openings that a augiens ant a was mal) cans now exist. ~ \ Tamed “souk Past OF nt freon _ GREER TRAINING MOST COMPLETE cele pli came 4 of 2 Yusine wot? Greer College of Automotive Engineering is a res- we usines che eo Our nese yaree® fidence trade school, not a correspondence school. cart: fa! $5 vow OW eels Thorough, successful training by actual practice, promt sy outer mus gisno™ Master Mechanic instructions insure personal, in- aseena Ww json © dividual training. Practical shop work on autos, 15S sin Cat trucks, tractors, all types of motors, ignition and por’ (aie starting systems. PICK YOUR JOB Select the position you want—make up your mfnd to come to GREER College and I will show you the easy road to lasting success. Thousands ZZ = have stepped into the ranks of Big Pay Men through GREER Training. ee Mechanics s.: P RI 7E See top of page 6 in front $ 25 0 In of book for full details RADIO & AUTO Storage Batteries CHARGED FROM LAMP SOCKET, for a Fe w Cents with an F-F BATTERY BOOSTER 2 tr a n ess PU aratingnatioRacemectort 06. 125Voltgeryciod C-Fzpe A-BCharges olt Auto & Up to 120 Tom Nah B RY: a es " Perfect hearing is now ree Batteries In Series Inductively At Home Overnight. onnecting “amma ' ctored in every condition of deaf-

Multipi ti U . No Grounds. All Circuits Separate. Nothing Like t Made. €-F BATTERY BOOSTERS are Complete Portable,

ness or defective hearing from | $ ftectifying Brontes Maintain Uninterrupted ’ causes such as Catarrhal Deaf- s Service, . Coogan Eeiciency. ene} wil r Mi ape . ness, Relaxed or Sunken Drum Yleve Doslan Denese earn Seen CLS

, Thickened Drums, Roaring an EA on Battery Terminals & 5 Belly

4“ Hissing Sounds, Perforated tf : Morning. Be Stil te Required. WS Wholly or Partially Destroyed : Save More Than Cost, POPULAR PRICES. YX Drums,Discharge from Ears, etc. A ie BE Tvve,¢ charges A 8 VoliBattery arg serps aH Wilson Common-Sense Ear Drums . Be ‘Ach in Combingtton of Types 6 ae i20 “Lite Wirlss Phones for the Bars’ secure 00 | QB WWMM (asinine ates ae ae enn fran sd Ay They are simple l — 8 Lower't Type ore foe peevy Fete, in devices, which the wearer easily fits into the ears = SOR er Compicte with, AMMETER h eth invisible. Soft, safe and comfortable. SE BATTERY CLIPS 11 to 16 Ibe. WiWrite éovay for our 168 page F REE book on DEAF Ne Home ipment, Orit f rite ‘0 A yn DEAF: AI Prom ’ NESS, giving you full particulars and testimonials. Charges Auto Bacio — wes buSER fe és WILSON EAR DRUM CO., Incorporated SROER Now or waite ienmme diate for TREE. 704 Inter-Southern Bldg. LOUISVILLE, KY. | Canadian Distributor: The Jack V. Elliot Co., Hamilton.O

Page 100

PO SRT Raia mis 8s ME ee Raligs we 114 Popular Science M onthly A New Butter - Kist Popcorn Machine at Half Former Price! ERE’S a marvelous money- making opportunity—a beau- tiful, new automatic Butter-Kist Popcorn Machine at half what former models cost. For a small down-payment this new Gold Mine Model will be shipped immediately to any responsible re- tailer. Within a few hours after its receipt you can be earning big profits, selling the world-famous Butter-Kist Popcorn, out of which you should easi- ly and quickly pay the balance. The “Gold Mine” is a beauty. At- tractive mahogany-finished cabinet. Handsome glass sides. Highly polished nickel parts. Takes up little room. Feeds, discharges, pops and butters the corn automatically. Keeps the corn warm and crisp after popping. gee thirty 10-cent packages an our. Butter-Kist Popcorn sells fast. It’s nationally known and advertised. People go out of their way to buy Butter-Kist. Out of every dollar’s worth you sell, you keep 65 cents as your profit! F. J. Studer writes, “My Butter-Kist Popcorn profits have averaged over $900 per year for six years’. R. C. Hoegge says, “‘First six months’ sales went over $2500’. Many are making even more. The “Gold Mine’ attracts custom- ers. Builds trade. Makes big profits. Write immediately for the new Butter-Kist Easy Payment Plan. Butter-Kist Popcorn **America’s Oldest Treat’’ HOLCOMB & HOKE MEG. Co. World’s Largest Manufacturers of Popcorn Machines and Peanut Toasters 2142 Van Buren St. Indianapolis HOLCOMB & HOKE MFG. CO., 2142 Van Buren St., Indianopolis, Ind. Please send me, without obligation on my part, your free Butter-Kist book. I also want the Location Chart which I will fill out and return to you. Name Street City and State Business The coupon filled in, will give you a quick start tewards big profits. No obligation on your part. Fill in and mail TODAY. BUTTER-KIST Popcorn and Peanut Machines THE HOME WORKSHOP The Tools I Use (Continued from page 113) use when sawing any of the harder metals, as it lessens breakage through cramped and wedged blades. One of my most used tools is my bench plate, which is made of a 1-in. section of a 6-in. square steel billet. This I shaped on both sides. I use one side for rough work and the other for finished work and laying out. Once I caught a neighbor trying to straighten a nail on the good side of the plate, and I made him think he had com- mitted an awful crime before I was through preaching to him about bench plates, their use and abuse. Of wrenches and .pliers I have a goodly number, of all shapes and sizes. My carpenter tools consist of a fine toothback saw, a crosscut saw, an all iron block plane, smooth plane,-wood chisels of many sizes, as well as gouges and carving tools. Ratchet brace and bits, expansion bits, a fretsaw, a turning saw for curved or circular sawing, a 10-in. pair of tin shears, together with a good husky blowtorch and soldering irons complete my outfit. With these tools always kept sharp and in the pink of condition, I am ready at any time to build a new experimental model or repair the many mechanical contrivances that are found in the modern home. How I Choose a Set of Tools for Repairing My Auto By George A. Luers ” SELECTING tools for my own tool roll and for my garage, I followed a definite plan that has proved satisfactory and economical. Starting at the radiator and working back to the rear axle, I ex- amined each detail of the mechanism of my car to obtain a good idea of the fastenings, bearings, adjustments, packings, and work- ing parts, and consequently of the tools necessary for making such repairs and ad- justments as might be necessary. This study resulted in the selection of a kit of tools, so that I am now never handicapped in making repairs. You may ask the result of this tool selection and care. Here is the answer: A thoroughly efficient car, free from roadside The garage equipment used and recommended by Mr. Luers CHAIN TYPE HOIST fon fi 2.8 SOLDERING COPPER 18" BREAST DRILL | TIN SNIPS ADJUSTABLE HACKSAW t4 MONKLY WRENCH HAND VISE oe - Y_ | 10° PIPE weeny i H K trouble, ready at any time for any desti- nation, and able to travel as fast as the law allows and sometimes faster. My collection of tools is somewhat larger than the usual because it has been gathered over a long period and the purchases have really meant economy in that I have been (Continued on page 115) Enjoyable concerts and maximum receiv- ing range are obtained only when your battery is fully charged. THE HOMCHARGER charges your “A” or ‘“‘B” bat- tery over night for a nickel with- out removing it from your living room. No muss—no trouble—no dirt—requires no watching. After the concert connect to any lamp socket, snap the clips on your battery and “turn in.” While you sleep the Hom- charger is silently charging your battery, the charging rate being governed automatically. In the morning it is fully charged. No other battery charger can boast of such quick and economical performance. The Homchar¢ger is the only battery charger combining all of these necessary Homcharg- ing features—Self-polarizing —five to eight ampere charg- ing rate— Underwriters’ ap- proval—beautifully finished in mahogany and old gold—un- qualifiedly guaranteed. Over 60,000 now in use. Sold complete with ammeter, etc., by all good radio and elec- trical dealers for $18.50 ($25.00 in Canada). See the Radio Homcharger Deluxe at your dealers or write direct for our free circular show- ing why the Homcharger is the best battery charger at any price. ; The Homchar¢ger will al: Motor ists charge your =. battery. The Automatic Electrical Devices Company 131 West Third Street Cincinnati Ohio LARGEST MANUFACTURERS OF VIBRAT- ING RECTIFIERS IN THE WORLD March Vu 7) Of". Om

Page 101

March, 1923 115 THE HOME WORKSHOP —— Auto Repairing Tools (Continued from page 114) able to keep my car out of repair shops. The tools that I consider indispensable to the car owner who desires a collection of his own are indicated in bold face type in the list that follows: For THE ENGINE: Spark plug wrench Spring compressor, adjustable Valve grinder 2 open end valve ad- justing wrenches Main bearing socket wrench Connecting rod socket wrenc Carbon scraper, 10 in. Wire scratch brush, 12 in. Contact file, 5 in. 2 contact adjusting wrenches For WHEELS AND WHEEL BEARINGS: Hub cap socket wrench Bearing adjustment open end wrench Rim bolt socket wrench Wheel puller, screw type For THE CLUTCH: Clutch spring adjust- ing open end wrenches Offset screwdriver, 6 in. Fork THE TRANSMISSION: Transmission bearing adjusting open end wrench and _— socket wrench For THE UNIVERSAL JOINT: Socket wrench Open end wrench For THE BRAKES: Wingnut spanner wrench Open end wrench For THE DIFFERENTIAL: 2 differential ad- justing spanners For GENERAL PurRPOSES: Screwdrivers, 6 in. and 12 in. Adjustable end wrench Ball ‘pein h a in hammer 34 1b. : Adjustable pliers, 5 in. and 7 in. Set of double end wrenches to fit bolt sizes, from 3/16 to % in. Set of sockets with wrench handle for same _ sizes. (These are obtained least ex- pensively in full sets.) It should be noted that the spanners and large sockets may be ob- tained through the car agencies, as they are fre- quently special sizes. For my garage tool equipment I have the following: ¥-ton chain hoist 3-ft. creeper 1-ton jack Bench vise, 4-in. jaws Emery” grinder, 5-in, wheel Soldering copper, 34 Ib. Breast drill, 18 in. Tin snips, 8 in. Blowtorch, 1-qt. size Hacksaw, adjustable Hand vise, 6in. Pipe wrench, 10 in. Monkey wrench, 14 in. Rawhide hammer, 1%4- in. face Ball pein hammer, 114 1b, Screw pitch gage Feeler gage Firm joint calipers, in- side and outside, 6 in. Rule, English and me- tric, 2 ft., fourfold Rule, steel, 6 in. Octagon reamer, 6% in. Rose countersink File, half round, 8 in. File, 3-square, 6 in. File, flat, bastard, 10 in. File, square, bastard, 10 in. Chisel, half round, 1%4-in. ade Chisel, diamond point, 5/32-in. point Chisel, cape, 34 in. Chisel, cold, 4%in. Solid punch, 5/32-in. point Prick punch Pin punches, 5/32 in. and Yin. Center punch, Cotterpin puller Tire tool Tire chain tool Bearing scraper, 8 in., 3 sq., hollow ground Screwdriver, offset, 8 in. Clamps, 4 and 8 in, Oilstone % in. SPARK PLUG WRENCH SPRING COMPRESSER VALVE GRINDER VALVE ADJ WRENCHES MAIN BEARING WRENCHES CONNECTING ROD WRENCH DIFFERENTIAL ADJUSTING SPANNER WRENCHES $50 to $150 a Week Wherever you live, Electricity offers you the opportunity to get ahead in the world. Expert Electricians are needed in farming communities, small towns, industrial centers, and big cities. The growing mileage of street car systems; interurban lines and electrification of great railroads brings a greater de- Simple, Easy Way to Learn Everything is explained in straightfor- ward, simple language. You learn easily, rap- idly and thoroughly. With every course we furnish a free Laboratory Outfit for practical testing and experimenting. You can become an Electrical Expert in less than a year, ready to take one of the many big-pay jobs that are always waiting for men who really know Electricity. PT er . _ American School a ai na +¢ad° ; Dept, E~375 = Pa a XN =—s«-S8th St, and Drexel Ave. a preset Aig me Sosy x (| Chicago choo! Sx. 8? ene ehnow x eric®™ 3759 98 P24 ooh will Sa jo . X DOE at specorn’’t ook wee . : 12s wwskepoctichy al v mand for big-pay Electricians yearly. You can become aPractical Electrician By Home Study To get an interesting, big-pay job in the Electrical field is not as hard as you may think. Anyone with an ordinary education can learn Electricity through our 50 weeks’ course in Practical Electricity, especially prepared for home-study. Thousands of men holding big electrical jobs got their start through spare-time study at home. Their success proves that you, too, can learn Elec- tricity without leaving home or giving up your present job. Send Coupon for Free Book This is your opportunity. Don’t let it pase. Fill in coupon and mail today. Get our ig free illustrated book “Your Future in Elec- tricity.” It describes the ——- in the Electrical Field—tells you all about the course andthe finefree Laboratory Outfit—reproduces many letters from successful students, with photographs of these big-pay Electricians working in their present jobs. Woon oe? oe oot? ee RIM BOLT WRENCH UNIVERSAL JOIN BRAKE ADJUSTING HUB CAP WRENCH SOCKET WRENCH || WRENCH BEARING ADJUSTING AND OPEN END OPEN END WRENCH WRENCH CONTACT POINT FILE CON POINT AD) WRENCHES FOR GENERAL USE GS” SCREWDRIVER 12° SCREWDRIVER !2° ADJUSTABLE WRENCH SSS EEE a) . A DIAMOND SENDIT BACK! ENTS’ 1 CARAT RINGS $3.97 \ You’d gladly pay $150 for a gome Diamond as perfect as this zi hiteLuxite Diamond .Only e: tell the diterence: Full SPE eLuxfeDIANOND | 5 f\ IF YOU CAN TELL IT FROM FREE REVERSIBLE COLLAR Here's your opport inity to try, at ouf expense, the biggest collar bargain on the market Linene Reversible Collars are made so that they can be reversed when soiled. Both sides are alike, of fine cotton cloth with stylish, starched finish. They are flexible, comfortable, and always smooth around the 9° ADJUSTABLE END WRENCH 74 LB BALL PEIN HAMMER 5° ADJUSTABLE PLIERS 7” ADJUSTABLE PLIERS TRANS BEARING ADJ i sence SOCKET AND neck. You save money because these Reversible Collars OPEN END cost less than laundry, and because by reversing them when soiled, you get two clean surfaces, Try them once 7 FREE LESSO aS and you will never wear any other kind of collar. EXPERT AUTO and MOTOR WORK Don't take our word for it. Prove it yourself, at our exy pense, by trying one. Without obligation to : (Atma | SPECIAL OFFER 2: esse shes: free sample as illustra- Se ee ee ee ee ee ted, if you will send but 2 centsin U.S. postage stamps Dept. PP = pg or postage and state your size. Write for sample today, Diagram showing that each tool in Mr. Luers’ kit has a specific use Earn $45 to $90 a week Boys, men--16 or over, - should write It should never be forgotten that the automobile represents an extremely success- a f i on , ful mechanical construction. The essen- a ai (a ensons in Moror and Auta, Operating snd Con REVERSIBLE COLLAR COMPANY (Continued on page 116) a io cncens geet a uceael "., | DEPT. 116 BOSTON, MAS& = Address

Page 102

Sa ens wa NN Rr OS ore OR eee “Four years ago you and I worked at the same bench, I realized that to get ahead I needed special training, and decided to let the International Correspondence Schools help me. I wanted you to do the same, but you said, ‘Aw, forget it!’ You had the same chance I had, but you turned it down. No, Jim, you can’t expect more money until you’ve trained yourself to handle bigger work.” There are lots of “Jims” in the world— in stores, factories, offices, everywhere. Are you one of them? Wake up! Every time you see an I, C. S. coupon your chance is staring you in the face. Don’t turn it down. Right now over one hundred thousand men are preparing themselves for bigger jobs and better pay through I. C. S. courses. You can join them and get in line for promotion. Mark and mail this coupon, and find out how. INTERNATIONAL CORRESPONDENCE SCHOOLS Box 7629-C, Scranton, Penna. Wituout 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: BUSINESS TRAINING DEPARTMENT [} Business Management Salesmanship [ |) Industrial Management Advertising [ } Personnel Organization Better Letters [ |Traffic Management Foreign Trade . |} Business Law Stenography and Typing |) Banking and Banking Law Business English r }Accountancy (including C.P.A.) [ Civil Service Railway Mail Clerk Nicholson Cost Accounting Bookkeeping Common School Subjects Private Secretary High School Subjects Business Spanish [J French [() Ulustrating TECHNICAL AND INDUSTRIAL DEPARTMENT Electrical Engineering D Architect Electric Lighting (Cj Blue Print Reading Mechanical Engineer ({) Contractor and Builder Mechanical Draftsman (Architectural Draftsman Machine Shop Practice L)Concrete Builder Railroad Positions (Structural Engineer Gas Engine Operating Chemistry () Pharmacy (Civil Engineer Automobile Work LiSurveying and Mapping () Airplane Engines () Metallurgy DiAgriculture and Poultry O)Steam Engineering 0 Radio [(jMathematics QOOUUOWWIW WLS INR 5. ois ceeubap cen peh bos bubeannnsunana seas ssensesoseseecornsssvenes Persons residing in Canada should send this coupon to the International Correspondence Scheols Canadian, Limited, Montreal, Canada, 6079 MarketPrice 4A a\\ 7 Will Buy 7 Ps Thia 3 . /o-4/16 Ct, fectly cut diamond, itaire, at $42.65 among its. See the many big am- lends mon on dia- ey . f Thousands o punpeid loans and other C a Day soon pays for a genuine 17 visible Underwood or L. C. Smith rebuilt eee, Save $20 to $30 on famous Larkin Easy-Pay- ment plan. Handsomely finished. 5 ear Guarantee. 30 Days’ Trial. Send for FREE Book TODAY. CC tac. Desk TPSM-323 Buffalo, N. Y. THE HOME WORKSHOP Auto-Repairing Tools (Continued from page 115) tials for its uninterrupted service are the maintenance, as far as possible, of its condi- tion when new, with only such adjustments as are due to wear and the renewal of broken parts that have become crystallized through continued stress and vibration. Since the tool equipment is solely for the upkeep of the automobile, it should be selected with care and not guessed at. Good care of the tools is essential. Each of my tools is placed in a definite location, either in the car or in the garage tool rack, and I am never at a loss to find it when needed. Each tool is carefully wiped of grease, grit and water, and is never abused. That is, a wrench is not used as a driver or a hammer to loosen screw parts. I take care to use wrenches that fit the flats of a bolt or nut, and never make an oversize wrench do, because that has a tendency to spring the jaws. The edge tools are kept sharp, particu- larly the nose of the screwdriver. I never pound on wrench handles, and make it a practice to keep tools off the seats and off the painted surface of the car, and never throw them down. When a job is com- plete, I put the tools back in proper order and, therefore, automatically obtain a check on them to see that none has been overlooked. Improvising a Generator Drive HE flexible shaft drive shown in the accompanying drawing was used to turn a generator for the electrical system of an automobile on which a burned-out gener- SLEEVE COUPLINGS ASSEMBLED FLEXIBLE COUPLING BETWEEN GENERATOR AND PUMP ator had been replaced by one that was too large to go into the bracket. The former coupling Had consisted of a circular disk held between two sleeve fas- teners. The improvised coupling was made by riveting into two sleeves the ends of a heavy spring. Over this spring a section of rubber hose was placed. This drive com- pensated for lack of alinement of the parts and provided a serviceable coupling.—G.A. . Your Auto Tool Box yee in importance to having a good kit of tools for your car is to have a convenient toolbox or compartment where they will be instantly accessible for road repairs. Several ideal ar- rangements for accomplishing this will be described in a forthcoming num- ber by Harold F. Blanchard, POPU- LAR SCIENCE MONTHLY’S auto expert. Popular Science Monthly Good Dancers Are Popular Everyone admires and wants to dance with the person who knows the latest steps. There is no need of being a wallflower! Arthur Murray, America’s foremost dancing teacher, has perfected a wonderful new method by which you can learn any of the newest steps in a few minutes and all of the dances in a short time. Even if you don’t know one step from another, you can — and easily master any dance without music and without partner, right in your own home. Your success 4s guaranteed. The Vanderbilts and scores of other socially prominent cere have chosen Mr. Murray as their dancing instructor. ore than 60,000 people have learned to become popular dancers * through his easy learn-at-home methods. New, Easy Way To show you how easily and quickly you can learn hig new way, Arthur Murray has consented to send, for but a limited time, a special course of sixteen dancing lessons for only $1.00. This extraordinary offer is made to prove you will enjoy learning the newest steps in the privacy of our own home—without onlookers to embarrass you. ou need not send any money now. When the postman hands you the 16-lesson course, just deposit $1 with him, plus a few cents postage, in full payment. If within five days you are not delighted, return the lessons and your money will be promptly refunded. This unusual offer may not be made again. Write today for the sixteen-lesson course. If you prefer, send the dollar now and we will pay the postage. The lessons will be sent promptly, in plain cover. Learn at home and sur- Prise your friends. Act now and be a good dancer soon. Arthur Murray Studio 618 801 Madison Ave., N. Y.C. The Only Avthentic Book on the Construction and Operation of “The Armstrong Super-Regenerative Circuit” Described fully in 52 pages Including 21 photographs and Hook-Ups in simple non- technical radio language. This set built by the author 4 Complete Description of Each of the Three Circuits Invented by MAJOR E. H. ARMSTRONG, E. E. How to Change a Regenerative Circuit to a Super- Regenerative Circuit Price $1.00 Per Copy Mailed or at your dealer DO NOT SEND STAMPS RADIO DIRECTORY and PUBLISHING CO. 45 Vesey Street (Room 106) New York City PATENTS Booklet Free Promptness Assured Highest References Best Results Send drawing or model for preliminary examination of Patent Office records and report as to patentability. All Business Given Prompt and Proper Attention WATSON E. COLEMAN, Patent Lawyer, 624 F St., Washington, D.C. Low Factcry to-Rider Prices. desired. Many boys to Pay mc ese Mead sortie: tnicage a a ee ee... ae ow

Page 103

nthly March, 1923 17

THE HOME WORKSHOP

7 —— Rolling ‘“‘Your Own”’ with the Simplest Cigarette Machine SMALL piece of tracing cloth and a meat skewer are all that is necessary to make a cigarette rolling “‘machine.”’ The 1 \ \ \\

\\ Bade ceiin © Jigs \\\ \ \ : \

il y er » ice i ingly simple and yet turns \ ASX \\\ a ae fo rolled do well as N ANS \ ‘ s N N \ 8 machine made “‘butts.”’ The cigarettes can be made thin or thick, tight or loose at will. The skewer or other small wooden rod of about the same diameter is split in half for 3in.from oneend. In this split is glued one \) \) \y \y \) N §

[Be eas in Get lak \\ \\ SS 4 1 DE ae FesS> N $

Twelve Million Cars, sixty million tires, millions of batteries and electrical systems to overhaul, repair and keep in running order. Get that picture well fixed in your mind, then you can begin to appreciate WHY the AUTOMOBILE Business is THE Business to get into.

Think of the opportunities in the TWELVE MILLION AUTOMOBILES

lancere repair and resale end of the business | mean—a line that would reach one and alone! Thousands of additional garages, one-third times around the world! Think wid battery repair shops, tire shops and what that means as a business oppor- r but-a welding shops are needed to care for tunity!! Can you think of a better field lessons says for ambitious, wide-awake men who ) prove these millions of cars. ‘ : acy a ; ; ; have been specially trained for that Bt Try to picture in your mind what _ kind of work? oe , in five ou Earn $2000 to $10000 Yearly today vl be How the tobacco and paper are placed in oun Piss, Eg geno sur- the “‘machine”’ when starting to roll on Endorsed by Big Factories Read These Letters é are doing it right now! BEoth “ < o~— EU. De ° Guaran 5 Vears . 2 : stick Gown the edge oO e paper Py erty ow al Pt am on ni ee SERVICE BUREAU oii P-BUCHSTEIN CO., 113 6th St., S., MINNEAPOLIS, MINN. How You Can Make Two AT < Ry TS IF YOU pete: ia Remarkable Radio Sets INVENTION and = mate | TO LEARN HOW TO 3 Mwcmibiena Geral cegetite |||) “- . SECURE A PATENT, send for Our Guide Book, ROW TO vacuum tube set at a cost of $20 or less, | GE. A PATENT, sent free on request. Tells our Terms, Methods, including phones and aerial, will be etc. Send model or sketch and description of your invention and we given in the April Home Workshop. om mee eee ee eee eee ill give our opinion as to its Another feature will tell how to build . bl t a receiving set with three stages of 1 patentable nature. — ponte mae anation: that pro- oS erry Tre Doeocecesesese eccccccce i . vides extraordinary tone volume and 5 clearness on the loudspeaker. STREET... .ccccccccoce SOPHO eee eee eee eee Ee eeE® l RANDOLPH & CO a CAT Or SPAMS Oba nok l 130 F St., N. W., Washington, D. C.

e -T oS

Page 104

118 =F ==> = bidicaiie ORME MASE: ry geek aa ean 8 + tt tpt st ot tee & &

eee

Registered Attorneys SERVICE Without charge or obligation, we will Agi inform you on any questions you "i may put to us touching on patent, @ s trade mark and copyright law, not requiring research. You may ask, “Should I protect myself by a patent, or register WP under the trade mark or copyright laws? What kind of a patent should I obtain? What will it cost? Will it sell?” and many other questions that may occur to you. These are vital points to consider, and questions will be cheerfully answered. IMPROVEMENTS WANTED Ask for copies of unsolicited letters from parties desiring to purchase outright new inventions and patents or to obtain licenses to manufacture and sell on a royalty basis. EVIDENCE OF CONCEPTION Before disclosing your invention to any one send for blank form ‘Evidence of Concep- tion,” to be signed and witnessed. A sample form together with printed in- structions will show you just how to work up your evidence and establish your rights before filing application for patent. As registered patent attorneys we represent LANCASTER 274 Ouray Building hundreds of inventors all over the U. S. and Canada in the advancement of in- ventions. Our schedule of fees will be found reasonable. The form “Evidence of Conception,” sample, instructions re- lating to obtaining of patents and schedule of fees sent upon request. Ask for them — a postcard will do. & ALLWINE Washington, D. C. Originators of Form “Evidence of Conception’”’

PATENTS Send us sketch or model for patentabilit: opinion and exact cost of patent. Our boo “How to Obtain a Patent” Sent Free on re- quest. It tells how to apply for Patents, Trade Marks, Foreign Patents, Copyrights, etc.; gives information

Only $45.00 For This Job Complete Save exorbitant freight rates and one-half

ple, complete

on Patent Procedure; tells what every i should know. Tt ds of I ‘8, who are our clients, are our references. CHANDLEE & CHANDLEE, 25 Years’ Experience 437 7th St. Washington, D. C.

ur- nished, all cut to exact fit. ny one can All Complete jassemble this job. Complete with hood, radiator shell, instrument rd, ppnolstering., metal parts, wood parts, iT . Flat radiator shell furnished made up. Designed low with lack of wind resistance. Price set up $90. Further particulars on request. The Central Auto Supply Co. Eng. Dept. 122 Louisville. Ky.

LEARN TO Study in the School that has the Long Established Reputation W. L. Evans’ Method is Simple and Easy to Learn Some of the cleverest cartoonists are former students. They had no experience before en- rolling, but worked at the lessons during their spare time, and found Cartoonist Evans’ METHOD “‘easy to learn’’ and are now making good money. It is not hard to learn to draw originals when shown in a practical way. The School is recommended by well known cartoonists because they know the students are handled right. If you like to draw and want to be able to sell your drawings, send a sample of your work (either a copy or an original) and let us see what you can do. We will send you the portfolio of car- toons and full details about the school. The Course is NOT EXPENSIVE THE W. L. EVANS SCHOOL OF CARTOONING

623 Leader Bidg. Cleveland, Ohio

Lack of High School training bars you from a successful business career. This simplified and complete High School Course—specially pre for home study by leading professors—meets all requirements for entrance to college and the lead- ing professions, 0 Other: o matter what your business come agen may be, oe can’t ope sue without spe- cialized training, Let us give urses you the practical training you need. Check and mail Coupon for Free Bulletin, American School Drexel Ave. and 58th St. ept. H.-375 Chicago — Dept, H.-375 American School Drexel Ave. and E8th St., Chicago Send me full information on the subject checked and how you will help me win success,

ineer actural Engineer sevees Business Manager evens Cert. Public Accountant coven Accountant and Auditor eseued cal Engineer evened Electric os and Power +....General Education evsees Vocational Guidance «Business Law ~

Name Address. -

Popular Science Monthly

| stance, the cell of any one-celled creature—

ey Man and His World (Continued from page 30) In addition to these things that all proto- plasm does, any particular variety of it usually has a lot of other things that it jg able to do. For instance, nerve cells can produce and transmit nervous signals. The cells in the green leaves of plants can make sugar. One and the same cell—for in- is often able to do 20 or 30 separate things at the same time. Why is this? How can one little piece of living matter do all these different things— breathe, eat, grow, reproduce? Scientists have not yet solved this mys- tery, but they are beginning to believe that it is because there exists inside of proto- plasm a very complicated kind of structure, something like a group of tiny separate compartments. In these compartments the varied activities of the cell can go on sepa- rately and yet side by side. Think of a factory in which automobiles are made. In it are many separate rooms where workmen hammer out the various metal parts or shape them or put them together. And imagine a giant so huge that this whole factory measures in com- parison no more than a thousandth of an inch. This giant would never see the single rooms of the factory at all. He would see only the entire building. He would notice that it ate coal and iron and that it gave birth to little moving particles that ran about by themselves. But how all this was done he would not be able to guess. Invisible Workshops of Life - Toward protoplasm all of us are giants. Its actions seem mysterious to us because we are not yet able to see into its separate workshops. When we learn to do so, we shall discover, scientists believe, that the things that go on in them are merely physical and chemical action, quite likes, the processes with which we are familiar.* And meanwhile we can trace a good deal of the past history of living things. We begin with the little slime speck of the ancient tide pools, a speck not unlike the modern cell, but far simpler in its structure. From this speck we believe that life grew and diverged, through eons of time, into the plants and animals we know today. What caused this divergence? It was caused by that fundamental law of life, the struggle for existence; the survival of the fittest; the rule that only the strong, the able, the inventive shall be allowed to live; the rule that in one form or another domi- nates the world and its inhabitants to this day. Fi This universal struggle for existence be- gan even with the living slime specks in the primeval sea. In the beginning, all of these specks were dependent for food upon what was brought to them by the water in which they lived. Presumably this food con- sisted of chemicals of various kinds, things that Nature had made before she began to produce life itself. Now, as the number of the living specks increased, the supply of food in the water began to run short. This was the beginning of competition. Some of the specks—we would call them the stronger ones—began to get more than their share of food; others began to get less. Then began what we know as effort. * A few of these processes have been duplicated. For in- stance, Dr. Alexis Carrel. famous research worker of the Rockefeller Institute, has been able to keep living cells alive and growing for years outside the body from which they came. Dr. D. T. MacDougal, of the Carnegie Institution, has devised a piece of apparatus, illustrated on page 21 of this issue, which duplicates many of the actions of a living plant cell.

March, a Some of get mor it no lor aimless! whatev' the livi | cision, ‘ tire COU | them n | other. | first br: | One | move. they h | somew | plentif | animal _ventur | poseful Ano | Jearne' | up cer’ _ in the | to cor | Plar | The | have plants | and tl | later < | out o | green | upon | For be pl | deed, | first | stem | tincti cells, short Ce had the s estal come greet more to st W | Tho: | our | food | else. | plan | turn | kno | it sc rest ba and Sor whi the mal wat

if sor pla the abo § late lon gell wh —_

Page 105

mthly ‘March, 1923 119 aga ———_—~©, | Man and His World | . e of the specks found that they could | Som ; - proto- | get more food by trying for it. They found of it it no longer advisable merely to drift about t it ig ‘aimlessly, letting the water bring them Is can whatever it happened to contain. And now . The the living specks made a fundamental de- make | cision, a decision that has affected the en- r in- tire course of life since that day. Some of ure— them made one decision; some made an- hings other. This was the first divergence, the first branching of the tree of life. ace of One group of the specks learned how to ngs— move. If there was not enough food where they happened to be, they learned to go Y mys- | somewhere else where food might be more . Protect Pe our’ Ideas : | ° e n ve e , or y new that plentiful. The specks of this group became combination of parts or improvements in any known article which roto- animals. They discovered the spirit of ad- [ecseenee its efficiency or wecttiness, sey be patanied. 5 & involves ‘ture, venture. They invented purpose and pur- IF YOU HAVE ANY NEW IDEAS ae). A agreertenpheerosage toward ‘protecting Seu rights, “if sou have. invented any new | a in 5 hb any ; 8 the | Another group of the specks took another machine, oF new Cosulinatian of parts or improvement, or new sepa- | road. They discovered that it was possible an ae oer | to manufacture « their own food. They of it Ea ohne ae )biles _ learned how to absorb sunlight, how to take WRITE TODAY FOR BLANK FORM yoms _ up certain very simple chemicals, abundant “Evidence of Conception i ie i to be returned i ying, descripti odel of y _ | . ~ —_ > Ang fry — idea. Pro. tly tbon receipt frre et your idea I will write you fully | a a © procedure and costs. huge | . NO CHARGE FOR THE ABOVE INFORMATION | — ° All icati in strict confidence. M 1, care- com. | | Plants—the World’s Food Factories gi iammsnianipeemen bit estat seticn™ , Spree eee of an | These specks became plants They still poe wh and prompt service—based upon practical experience. Highest ingle have this power of making food. Green Write to-day for freé book ‘‘How to Obtain a Patent.’’ This book | . ° ° - ill giv valuable i ion, and it ma i h time d see plants still absorb sunlight in their leaves and eflort. Send fort NOW. | ; : : M bn te-dew ivel United States and forei _— and they still use this, as we shall see in a patente and trade marke" Very probably I can help you. Write today. gave ' later article, to manufacture food materials CLARENCE A. O’BRIEN, Registered Patent Attorney ran ' out of simple non-living chemicals. The 1800 Southern Building es om we en D.C: } Was | green plants are the chemical food factories CLARENCE A. O'BRIEN, 1800 Southern Bldg, | upon which all life depends. Patent Attorney, Washington, Dd. ic. | ° ‘ Please s y > book! ie; | For the primeval specks that decided to Obtains Potent and blank form “Evidence of | be plants, motion was unnecessary. In- Conception"’ without any obligation on my part. ants. | deed, it might be a handicap... So these Name ause | primeval plants learned to sit still. They irate | developed rootlike projections that held a (writ CLEARLY) , we | th 2m fast to the rocks. - the | This was the origin, we believe, of the rely | first great distinction between the plant | g ikes, | stem and the animal stem. Another dis- ir.* | tinction followed very soon. The animal | O ou a Nn ‘ deal cells, reproducing rapidly, began to grow | We short of food again. the Certain of their cousins, you remember, r y the had settled down on the sea bottom near ea Ou ea e ure. the shore where the light was good and had e Tew established f tories. pe — : 1 ood factories. | They had be EAD a few of the many letters we have into come plants. The animal-like specks cast a received from Dictograph Loud Speaker day. greedy eye on these supplies of food. What users. You, too, can enjoy the utmost in was more natural than that they should decide Loud Speakers if you own one. the to steal it? They learned to eat the plants. HANNIBAL, MISSOURI MONTEREY, CALIFORNIA = ae animals have done this ever since. “We have been using your J purchased one of your e ose pirate specks, our ancestors, invented Radio loud epesker aad the co mame og wom — . z . . ‘ Tanci ave tri 1 ive; our particular way of meeting a need of results appear to the writer out thoroughly and am more ymi- food. They took it away from some one better than we can obtain — — Pye it. I can this else. To this day all animals live by eating using any other style speaker. Angeles and Salt Toke City J plants or by eating other animals who, in a i. Se be- turn, have lived on plants. Plants alone Manitoba come in clear and = FPUSE I Detairs, and some the know how to feed themselves. They know oe pe —. —— Sa oo : p miles or “sr it 4 -_ that -~ are able also to feed the speakersnowon the market.” more can be plainly heard.” ha | Test of the world. ATLANTA, GEORGIA lich | ¥ first the distinction between plants TR, Tee “I find your Loud-Speaker 0 0 on- and animals was probably not a sharp one “Believing that ameritorious —_ very satisfactory indeed, it is $ ‘ ‘ article should be endorsed, the only real good loud “4 — whiny — — undecided for a i oud to _—_ a I - ———- I ee seen for P RICE oe 1 to while which path to take. They combined using one of your Dictograp omeuse. It works perfectly . s hie d is all laim for it.” r of the characters of plants with those of ani- Hem - cr poor nn ee ee Complete with 5 ft. flex- a adn < d son gpl : from Maine to Californiaand ORFORD, NEW HAMPSHIRE ‘ ty) als. Indeed, there are still alive some tiny ee ' ibl d, ad ‘hi 3 : from Canada to Cuba. Be- “Your Radio Loud Speaker #0! Cord, a apted for re- is water creatures like this—creatures that are fore buying I compared it works fine. I was a little ceiving sets with Detector 2 of somewhat like animals, somewhat like = by = with another afraid about getting it, 2-2 dt t fA lif oud speaker costing more got stung on one so c an wo stages O mplifi- = — They are green and they can feed than ey the —, = — — —_ I cannot cation © - emselves yours. t has a autiful, make work; but not so with ° ogg about + OF plants do, but they can move clear tone and is very neat the Dictograph, as it works If deal ’ : : as animals do. in appearance. I “tune in” good as a loud speaker that your dealer doesn’t ort. Scientists call these creatures flagel- Fagen tpg a T heard that cost more thas _ carry the Dictograph Loud wii lates because they possess one or more head set.” think the music is better.” Speaker write us direct. fhe ag threadlike attachments called fla- they ella ich i ti ay gella, which is a Latin word that means | DICTOGRAPH PRODUCTS CORPORATION 1 of whip lashes. The creatures wave these . Sienshendealt . | (Continued on page 120) Suite 1311, 220 West 42nd Street (Bransher in all New York City

Page 106

*~ bares ae papa epee ae nt M 120 AN_AN Aya Pntint adh ~ A AAA | | @,\ and by reasonable fees. a IAA Bh AR JAAR Vide - Main Office, 6 Owen Bldg., Washington, D.C. Aerid me \ = Inquiries from Manufacturers and Others Who Are Looking for Good Ideas PROTECTED BY PATENTS are constantly being received. Manufacturers are always interested in any new device for which there is a market, which fills a long felt need, makes production possible at a lower cost, or which will do the work BETTER. There is undoubtedly a great demand to-day for really worth while inventions. Your First Step If you have an idea, send immediately for my blank form ‘TO RECORD YOUR INVENTION.” You should serve your own best interests by filling out and signing this form before you disclose your invention TO ANY ONE. This document will help you determine and establish evidence of invention before filing an application in the U. S. Patent office. A copy, with full instructions, will be gladly sent on free request. New Book ‘‘Successful Patents’’ Sent FREE Every man who has an invention or ever hopes to have one, should send for a copy of my book, “SUCCESSFUL PATENTS.” It tells what everyone should know about patents, trade-marks, copyrights, etc. It describes my methods, fees and terms, gives information relative to assignment or sale of rights and instruct‘ons in detail. Mail coupon to-day for a free copy of this book—or a postcard request will do. To the Man with an Idea I offer a comprehensive, experienced, efficient service for his prompt, legal protection, and will endeavor to aid him in the commercial development of his proposition—my service is distinguished by over 12 years’ successful practice, and by thousands of satisfied clients Send sketch, or model, and description, for advice as to cost, opinion as to its patentable nature, etc. Preliminary advice gladly furnished without charge. RICHARD B. OWEN, Patent Lawyer 2276-D, Woolworth Bldg., New York City Please send me, without charge, or other obligation, a copy of your book, “SUCCESSFUL PATENTS,” your form ““‘TO RECORD YOUR INVENTION,” and information concerning patents, etc. RA ARS? . I A AK AK AR AR ARS Branch Office i om ww. LATA 1212! GO) 9) F' D'S O'S) 9.8. Seem eee eee ree es eee reese ssereseesesesesesee ey ORO BESO TERRIER a As one of the oldest pat- ent firms in America we give inventors at lowest ’ m” consistent charge, a service noted for results, evidenced by many well known Patents of extraordinary value. Book, Patent-Sense, free. Lacey&Lacey, 648 F St., Wash., D.C. Estab. 1869. PATENTS TRADE-MARKS COPYRIGHTS Send for our free book of patent information Beale & Par 804 F St., Washington, D. C. 16 S. Broad St., Philadelphia, Pa. CAN YOU . think of a simple, practical idea that will fill one of the many re- quests we have on file for new inven- tions? It may mean a fortune for you. Thousands of things are needed Ricut Now. Your brainscan help. Send to- day for our great new book—“‘Inven- tions and Trade Marks, Their Protection and Exploitation’’ and learn more about making money from ideas than you ever knew before. It tells many things that are wanted, too. A postal willda— it is free. y PATENTS ADVERTISED - For SALE FREE In INVENTION And MANUFACTURING SUPPLEMENT. Published for the man with an idea. Send for free sample copy. One year’ssub- ill ecription 50c. We help our clients, without charge, to get the dollars out of their ideas—having facilities none others possess. ‘ Advice free. Don't delay—get the , book at once. AMERICAN - INDUSTRIES, INC. 201 Patent Dept., WASHINGTON, D. C. Lights the road for 1/3 of a mile! VERY man needs ‘this reliable electric lantern around the home, in the garage, for his workshop. And men who shoot and camp will find this lantern essential. This super lantern throws a beam o light three city blocks. The adjustable focus screw enables you to obtain all degrees of light from a strongly concentrated beam to a broadly diffused light. The sturdy alumi- num case and soundly made connections make it impervious to weather and hard knocks. To find anything on the high shelf—for use in the cellar—to work under your automo- bile—and for scores of other purposes you will find the ABLETT ELECTRIC LANTERN indispensable. Operates on two ordinary dry cells, giving it exceptionally long life. This lantern is made absolutely waterproof, moistureproof and gasproof; and it will last a lifetime. Order one today. Enclose check or money order—or we will ship C.O.D., complete with batteries for........-- z Si RRRIEES So 5 5 oo 6070 2 eo dnee'e se 7.50 CHARLES R. ABLETT CO. 199-201 Fulton St. New York, N. Y. SE SEER oR Popular Science M. onthly Man and His World (Continued from page 119) whip lashes about in the water and thus drag themselves along. Many bacteria that cause disease in our body also move by means of flagella, and scientists suspect them of being degenerate descendants of these primeval plant animals. The surviving green flagellates give us, probably, some idea of what the primitive plant-animal cell was like, though we must not imagine that it was exactly like them. Every creature alive today has precisely ag long an ancestry as we have. The flagel- lates have changed less than most others. The real question is why we ourselves have changed so much. Why are not all of us still one-celled water creatures yanking ourselves along by waving threads? The answer is that we have been forced to change. As the flagellates multiplied in the primeval sea, they began to compete with one another. There was not room for an unlimited number of them. So some of them began to live in colonies and became sponges. Others formed tubelike groups and became worms. The Drama of the Living Past Presently there were too many worms and some of them were forced to crawl up out of the sea into the rivers. These, as we shall see later, became fish. And after a while there were too many fish, so that some of them had to leave the water and live on shore. And out of these land dwellers there came, in the course of ages, man. Thus runs the story of evolution, the great drama of the living past. The his- tory of the rise of life; of lowly worms creeping about in the mud, of fish learning how to breathe air, of great reptiles drag- ging their 60 tons of flesh and bone along the shores of ancient swamps, of curious little catlike creatures peopling the forests of lands,now buried under arctic ice, of how these creatures grew, at last, some of them to be monkeys, some apes, some men. This is the story we shall tell in later chapters of this serial. But first we must tell how the story started. Life began, we say, in the primeval sea, but what produced this sea? Was the earth always cool enough for life? Or, if it was once molten, what melted it? How did it grow and how was it born? What pulled it, in the beginning, out of the very body of the sun? And how did this sun of ours come into being among the great assembly of the other stars? How did it happen, in short, that there came together here on this little dust mote of an earth, in the midst of the vast void of space, exactly that combination of heat and light and water and chemicals that made it possible for life to start? This is one of the greatest mysteries still tempting the imagination of mankind. How modern science has begun to pene- trate this mystery; how it has picked up the beginnings of the trail of life, the trail that leads down through unnumbered ages to end at last in man, will be the subject of our next chapter. For Further Reading The subject of this article is fascinatingly discussed in Dr. Henry Fairfield Osborn’s ‘“‘The Origin and Evolution of Life” (Charles Scribner’s Sons, New York). An excellent brief account of the evidence for the evolu- tio idea is “Evolution and Animal Life,"” by Dr. David Starr Jordan and Dr. Vernon Kellogg (The Macmillan Co., New York). ft A On the scientific questions involved in the origin of life, a good short summary is ‘The Origin and Nature of Life, by Professor Benjamin Moore, — as Volume 63 of the low-priced Home University New York). ibrary (Henry Holt & Co.,

Page 107

1 thus ia that ve by uspect nts of ve us, mitive > Must them. sely as flagel- hers. ‘selves ; all of inking forced lied in mpete m for me of ecame roups 14 vorms wl up as we fter a some ve on ellers le , the e his- 7orms rning dra,- bone 8, of g the ic ice, me of men. later must | sea, earth > was did it ulled body ours mbly there mote id of t and made 5 still kind. pene- d up trail ages bject | in Dr. ‘ion of - evolu- David an Co., of life, | Life,” > 63 of &Co., - Pa 4 March, 1923 ——————— THE HOME WORKSHOP Making Money as an Amateur Portrait Photographer IKE millions of others, I owned a cheap camera and soon filled an album with interesting poses of every member of the family, but, as my wife often complained, the portraits were not “finished” like those taken ‘‘at the photographer’s.” Critical comparison brought out the fact that the homemade portrait, if taken out of doors, usually showed “‘sun squints’’ and too much contrast between light and shadow, while those taken inside included sections of furniture or wall paper that could not qualify as good _ back- grounds. The professional pho- tographer’s por- traits, on the other hand, usually started at the bottom with a solid, dark color that gradually “‘dissolved”’ into a soft, evenly lighted likeness of the sitter, against a background that was either a dark shade or a dark, hazy design. To obtain a solid, dark colored fore- ground that would “dissolve’’ into a like- ness of the subject proved a simple matter. I procured a piece of black cardboard as wide and twice as long as my camera, and to one end of it, at right angles, I fastened another piece of black cardboard by means of a paper “hinge.” This piece was the same width and high enough to reach the center of the lens, as illustrated. The middle of the upper edge was then cut away on a curve of the size and shape de- sired for the finished print, and ‘‘toothed.”’ A piece of dull black oil- cloth, 3 by 4 ft., tacked to a window shade roller, furnished a neutral dark background in conveniently portable form. A homemade portrait subject good diffused light, hung the oilcloth behind and set the camera on a table with the “saw teeth” directly in front of the camera at a distance of about 1 in. less than the length of the camera. Then I located the subject in the finder and made the exposure. Because of their good quality and rea- sonable price, added to the fact that they can be conveniently made in the subject’s own home, these amateur portraits, mounted in neat but inexpensive folders, enable me to offer my customers a service that fits in midway between the often un- satisfactory homemade “snapshot” and the higher priced work of the professional photographer.—GLEN WILLIAMS, Detroit, Mich. The vignette attachment INSTEAD of wiping off surplus paint from a brush on the edges of a paint can, drag the brush against a wire run across the center of the can at the top. The wire can be run through two holes punched in the tin with a nail. I placed my | in a| sano TRADE-MARKS AND COPYRIGHTS pe oe SPECIAL OFFER PATENTABLE NATURE Before disclosing an invention, the inventor should write for our blank form ‘Record of Invention.”’ This should be signed and witnessed and if returned to us together with model or sketch and description of the invention, we will give our opinion as. to its patentable nature, Our Three 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 Movements illustrated and de- scribed, Articles on Assignment or SALE OF PATENTS, Patent Practice and Procedure, and Law Points for inventors. " OUR TRADE MARK BOOK Shows the value and n ecessity of Trade-Mark Protection and gives information regarding Trade-Marks and unfair competition in trade. OUR FOREIGN BOOK A We have Direct Agencies in all Foreign Y Countries. We secure Foreign Patents in shortest-time and lowest cost. LIST OF PATENT BUYERS SENT FREE IDEAS WANTED: Send for LIST OF PATENT BUYERS, containing unsolicited Letters from Manu- facturers and others WISHING TO BUY merito- rious patents. There iea great demand for NEEDED We endeavor to assist OUR clients in the commercial develop- INVENTIONS. ment of their inventions. ’ SPECIALIZATION Our Staff The field of invention is so vast that it is impossible for any one to become an expert in all the different classes of invention. For this reason Victor J. Evans & Co. em- ploy a number of patent lawyers and mechanical experts who have been selected for their special knowledge and ability in certain lines of invention, THE VALUE OF YOUR PATENT Will depend much upon the skill and care with which your case is prepared and prosecuted in the United States Patent Office. Every case receives our best efforts, and our work is done consistently, skillfully and thoroughly, as is evidenced by the many unsolicited letters of commendation received from our clients. We will furnish lists of clients from any State in the Union for whom we have secured patents. Our New York, Philadelphia, Pittsburgh, Chicago, and San Francisco Offices We have ee for the benefit of our clients Branch Offices in New Y ork City, Philadelphia, Pa., Pittsburg, Pa., Chicago, Ill., and San Francisco, Cal. These branch offices located in these large commercial cities, together with our Main Office located near the U.S. Patent Office, in Washington, enable us to more promptly handle the business of our clients, particularly as the branch offices are in constant touch with the Main Office. Highest References—Prompt Attention—Reasonable Terms \ . \47) VICTOR J. EVANS & CO.; \N Til Patent Attorneys i I | Ni Philadelphia Offices Pittsburgh 514 New York Offices Offices i 1007 Woolworth Bldg. ire Bldg. 714-715 Liberty Bidg. : mi | » } Chicago Offices. 1114 Tacoma Bldg. San Francisco Offices, Hobart Bidg. i | i LS} iN Main Offices, 760 9th Street, Washington, D.C. 1 | i | il xuiD Gentlemen: Please send me FREE OF CHARGE your books ; Aa de coctcanas Silos igen } ee re eee, a TE ae RE LITT LO CR hm aan

Page 108

a ee eee

122

Brooks Variable

Nibdilj,

Condenser Two Ribbons Furnished Easily Interchangeable (Max. .0005—Min. .00001) (Max. .001— Min. .00001)

Adaptable to all receiving circuits. Shorting of plates eliminated. Nicety of Adjustment. Straight line capacity curve, Low internal resistance. Loud Signals. Retail $ 4.75 each Price Complete with Dial

and

JOBBERS WANTED Write for Prices Discounts ERIE, PA. Manufactured by METRIC METAL WORKS American Meter Company, Inc.

VAuS FORD ‘2 SPORT CAR Other types down to $3.50. Famous sure fit, Agg+xr. life-

size patterns and picture instructions show how. You can easily convert ‘es Ford into ed ies oo *\ — ie eds have done with afew dollars worth of material ‘ t] Keen, Classy atterns, Pres ieee low, ten wctitttiy, Street Rear on on de ig ow, rides wonderfully eas rder ifdy’’ Topa and **Gosum*’ Windshields.

good delivery. Send 5c ¢ coin for tilugtrated Ku ie port Bodies, UEMPEL CO. 515 ‘Kuem pel Eldg., Guttenberg, lowa

A great and rapid seiler, some- thing every boy wants and never gets tired of; scientifically and VY practically made. If you like hunt- ing and outdoor sport get a Zip-Zip. Prong made of beautiful metal. Fine Zip-Zip rubbers with plenty of pep and force. Order from ys or your dealer. Zip-Zip complete, 35e, or three for $1.00, Automatic Rubber Co. a Dept. 22, Columbia, S.C. Gamggglije, ,

AGENTS 222% PROFIT $60-$200 per week. Free sam- ples GOLD SIGN LETTERS for store and office windows. Anyone can put them on. Big demand every- where. Liberal offer to general agents. METALLIC LETTER CO., 433A N. Clark, Chicago

NO MONEY DOWN EASY TERMS Save Big Money OLIVER Speedie Here is the newest Oliver—the handsomest

cooeen 5 ees. finest and most Popo standard we ever built. The triumph of 38. years of orem ssn facturing. We don’t ask you to buy it first. Ali we ask is that you send for it and try it FREE for five days. Note how easy and quiet is its action. Note the countless im) Fastest ments and refinements that feature it. It is the fastest writer we ever built. No human hand can write fast enough to tax its speed. And we offer you this amazing new Geourtter at the lowest price and the lowest terms offered anywhere for a new standard machine. TEST IT AT OUR RISK Don’t senda penny. We will ship you this wonderful type- writer for you to try out in yourfown home or office. hen if you are delighted with it you can pay for it on casy terms, a little each month, If not, return it at our expense. We take all the ris‘. You are under no obligation. Write for our amazing FRE E TRIAL OFFER. Dealers and agents wanted every where in unassigned territory. me RT RL EN — Ee? serene The Oliver Typewriter Company, | 1103 Oliver Typewriter Building, Chicago. lease send me, without obligation, your catalog, FREE TEAL OFFER, easy F neers and cash discount I on the new OLIVER ter. { BENE. ccdveccsotcovescekecceseccsecespencncnccvcconsessces | Rh a. cntannscgonigietniaetondinensnas i cc cl |

Popular Science Monthly

THE HOME WORKSHOP

How to Do Simple Lathe Work without a Lathe By Howard Greene MANY a time the amateur mechanic comes to a stopping place in his work for lack of a lathe. Yet in a large n«-mber of cases the obstacle can be surmounted satisfactorily. A \-in. hole in an iron casting, for in- stance, had to be enlarged, for a depth of an inch, to in. This is how it was done: A piece of cold-rolled steel rod was found that was a snug fit in the hole. Through this a 1-in. hole was drilled. A cutting tool was made of a scrap of )¢-in. round tcol steel or drill rod, and this was driven into the hole, in which it fitted tightly. With the cutting end projecting about 1/64 in., the “boring bar” was inserted in the hole to be enlarged and the cutter was brought against the casting. The tool was turned by means ofa handle clamped to the end. When the de- sired depth was reached, the cutter was driven out with a punch until it projected 1/64 in. more, and the process was repeated. Once the tool had been made, the actual OO mm DETAIL OF CUTTER BORING BAR

CLASS PING So FREE CATALOG Sits ano wumoen in cuass rrotitene# Either pin illustrated made with any 3 let- © | bf ters and 2 figures, oneor two colors enamél. ‘

‘A Silver plate, 206 es., $2 ~~ doz. Sterling a silver, 400 ea., $4.00 doz. Write for catalog sS 4 Fa sterling and solid gold pins and rings, Bastian Bros.Co. 450 Bastian Bldg., Rochester, N.Y.

| Radio A meeting pd Sica | _ ACME APPARATUS co. ‘ R

ADJUSTABLE BEARING A simple hand boring bar and an ingenious homemade adjustable bearing work required only half an hour. For big- ger jobs of the same sort the tool could be turned with a brace; but for small work, turning by hand is much better, as very little ‘‘power’’ is required. It does not do to try to take too heavy a cut; quicker work can be done with a number of light cuts. When disks of wood, fiber, and sheet metal are wanted, it is really easier to cut them with a common gasket cutter than to make them in a lathe. The important thing is to have the right kind of a cutting tool. No difficulty has been experienced in cutting fiber disks 6 in. in diameter up to 3 in. thick and brass disks 4 in. in diameter and 14 in. thick. It simply calls for a little elbow grease and a properly made cutter which has plenty of clearance, so that once the cutting edge has begun to work down, the tool will not rub and bind and make the edge of the disk ragged. A gasket cutter can be bought in any hardware store for less than a dollar, but the cutters will be found of little or no use except for very thin stuff. A new one will have to be made or, what is about as good, a new cutting edge can be ground on the butt end. Hardening and tempering will soften the original cutting end, but this will not matter much. A grooved pulley to take a 3/16-in. round belt, which is the size of the ordinary sewing-machine belt, can be made from three disks of 1%-in. fiber screwed together with machine screws, the fiber being (Continued on page 123)

mtretaeramda a & ce a hl ee ee eae a,

Page 109

hly wm 8 OD ett US Ge on— « March, 1923 [ss THE HOME WORKSHOP | drilled and tee as if it were metal. A | yattail file 14 in. in diameter at its thickest part will cael out the groove. The center disk should be cut so that when the three are put together, there will be a groove \% in. deep. To fasten such a _ permanently to | the shaft, drill a small hole through the | shaft to take a bit of steel wire—a wire nail | is excellent—long enough to project about half the diameter of the shaft on each side. Cut a groove in the middle disk so that when the disk is slipped on the shaft, the wire pin will fit snugly in it. Then the out- side disk is put on the shaft and the whole pulley screwed together, locking the pin and pulley solidly. This is a most satis- factory arrangement. Pulleys made in this way should be solidly screwed together, especially if they are more than, say, 3 in. in di- ameter. A 4-in. pulley should have about six equally spaced screws, all as close as possible to the edge. Glue : may be used, but it is not re- ™— liable by itself, as it does not stick well to the belt fiber. The writer has a small countershaft car- rying a 4-in. pulley and a three-step cone, 144, 2 and 214 in., on a shaft of 5/16-in. steel drill rod. This is used to drive a small lathe and transmits the power of a 1/20-hp. induction motor, 3/16-in. round belting being used. The pulleys were made before the lathe was obtained and there is no lathe work on them, but they have been _ fully equal to the requirements, and the | only result of six months’ hard labor has | been in smoothing them and making the belts grip better. Incidentally, the belts are laced with the gut of old violin E strings. How Bearings Were Made The bearings for this shaft were made in a rather unusual way and one that has | worked out extremely well. Each bearing was made of two pieces of ordinary brass bar stock, 144 by 34 in. For each bearing, two pieces of the brass were cut long enough to give the bearing the proper height and they were joined with two 4-in. machine screws, making one piece 4 by % in. The hole for the shaft was drilled through the 4-in. way. Then the two pieces were taken apart and split at the sides with a hacksaw and drilled and tapped for \%-in. machine screws for closing ,up the hole to take up wear. The peculiarity of the ar- rangement is in the fact that one of the halves of the bearing is split on the right and the other on the left. This makes pos- sible a very fine adjustment. As it is almost impossible to drill the bearing holes quite true with a hand drill, they were drilled 1/64 in. under size and reamed in position with a round file, finally being ground true with fine emery and a piece of the same drill rod used for the shaft. The “reaming” with a file is a me- chanical crime, but it worked well. The bearings are mounted in a 3/16-in. brass plate by means of two 14-in. machine screws running up through the bottom of the plate and countersunk. After six months, there is so little shake that it is very difficult to detect it. 123 PATENTS Seventy-six Years of Practice HE firm of Munn & Company filed its first application for a patent in 1846, and for seventy-six years has endeavored to keep pace with the inventive genius of the United States. An experience of many years is at your disposal. If you have an invention which you wish to patent, send your sketches or model together with a description of your device, explaining its operation, and you will receive prompt, courteous attention. Write for our Handbook on PATENTS A full and complete booklet on Patents, Designs, Trade- Marks, Foreign Patents, Copyrights, Labels and Patent Office Practice with an explanation about our methods, terms, etc. All communications strictly confidential Keepin touch with the inventions of the world by reading SCIENTIFIC AMERICAN The MONTHL Y MAGAZINE with a special appeal to every man of inventive genuis. Recent rulings of the Patent Office, descriptions of the latest patented inven- tions, legislation and court decisions affecting patents, are noted in this authoritative publication. ' MUNN & COMPANY Patent Attorneys 683 Woolworth Building, New York City Scientific American Bldg., Room 3, 625 F Street, Washington,D.C. 801-D, Tower Building, Chicago, Ill. 611-A, Hanna Building, Cleveland, O. 602 Hobart Bidg., San Francisco, Cal. introducing the New Sun Auto- . ic ator and Timer, : tomatically Your choice of the World’s best typewriters —Underwood, Remington, Oliver—full size, late model, completely rebuilt and refinished: brand new, Prices smashed _ to almost half. $8.50. Large income for mendous sales opportunities. AUTO SUN PRODUCTS COMPANY. Dept. 32 Cincinnati, Ohio oe

Page 110

ro eo 3S Invention Now Tau ght a Great Inventors. Now Show You How to‘ ‘Make Your Ideas Pay Thousands of inventions are needed today. Just one little idea can bring you fortune and fame. The world is waiting for new inventions in engineering, chemistry, household articles, radio, and other fields—and will pay big money for even the simplest idea. Little things like the tin bottle cap, the crimped hair-pin, the rubber on the end of a pencil brought their inventors hundreds of thousands of dollars. Couldn’t you make some equally simple Popular Science Monthly THE HOME WORKSHOP Small Motor-Driven Fretsaw Is Simple in Form By Ernest Bade A SIMPLE fretsaw for light work such as toymaking and cutting out panels with pierced designs and puzzle pictures, can be constructed quickly and easily along the lines shown in the accompanying illus- tration. The framework of this saw is made from metal strips taken from a toy con- struction set, but other material will serve as well. The first step is to make a table and its support. This must be as rigid as possible and so made that it can be securely fast- ened to the worktable or bench. The w.vle support can consist merely of a box placed upside down on the table, the far side being removed. The saw holder or Build a business Saving Coal It’s easy to sell the public coal-economy— and it’s profitable. Become distributor for the much-demanded CROWN Fuel Saver. Thousands in use. Saves at least 1/5 the fuel. Many users get saving up to 50%—smoke reduction 25% to 75%. Build a permanent business with sure and steady profits. Every distributor aiced by strong advertising, helpful sales literature, and free training. We show you how to sell the CROWN and help you do it. If you want a business that requires little investment but that offers splendid profit- making opportunities—write or wire for our exclusive distributor proposition. C. F. S. CO., 12 N. 10th St., Richmond, Ind. invention? Haven't you ideas that could be turned into money? “Lighting Fixtures” ap TIP oe ae (ALARM RET ES ae i guesswork. Invention is based on certain ufacturers. principles, just as any other profession. It fol- - i lows a definite course of procedure step by step Completely wired : from the origination of the first idea to its final te if Rare oon ee re _ — Inventing isn’t a mat- ter of blind luck—it isn’t a question of RAYMOND FRANCIS YATES development on a commercial scale. Learn at Home in Spare lime Hitherto, every inventor had to work out these principles of invention for himself. For every successful inventor knows and uses these principles. He knows WHAT TO INVENT, HOW TO INVENT, HOW TO PROTECT HIS RIGHTS and HOW TO MARKET HIS PATENT OR INVENTION. But now you can learn in a few months what it took great inventors years of discouragement and terrific struggle to acquire. Fifteen famous inventors have now re- vealed, for the first time, the secrets of invention. They explain how to originate ideas, how to develop and perfect your ideas, how to patent your inventions, and how tosell them to your best advantage. Inshort, they make it amazingly easy for you to become an inventor, simply by learning the whole wonderful science of invention, step by step, from beginning to end. It requires just fascinating moments of your spare time at home. First Course of Its Kind This is the first course in practical Invention that Although made of toy parts, — fretsaw serves well for ight work frame consists of two strips, a block and a spring. The long strips can be made of wood or simply be hollow tubes or fairly thick metal strips. A few inches from one end, one of the strips is fastened se- curely to the block; the other strip is pivoted to the block by means of a bolt, so that this arm is movable. The spring con- nects the shorter ends of the two arms. This rocking beam is then loosely fast- ened with a bolt to two arms projecting from the back of the table. The whole beam should rock up and down freely. A grooved wheel is fastened to the lower part of the table and connected with the front end of the lower rocking arm by means of a lever or connecting rod attached near the rim of the wheel. In this way the circular motion of the wheel is translated into an up-and-down movement. The saw blade is clamped to the upper and lower Ready to hang. Direct from man- Rt J A including glass- ware. Send for Catalogue No. 24 and Dealers’ proposition ERIE FIXTURE SUPPLY CO. Desk A, Erie, Pa. Here’syour opportunity. Radioneeds you. Win success in this fascinating field. Trained men in demand at highest salaries. Learn at home, in your spare time. Be a Radio Expert I will train you, quickly and easily, to design, construct, install, operate, repair. maintain, and sell all forms of Radio apparatus. My newmethods are the most successful in existence, Learn to earn $1,800 to $10,000 a Year - R E E Wonderful, home-construction, tube receiving set, of latest design. Write for‘‘Radio Facts’’ free. Engineer Mohaupt. American Electrical Association has ever been devised. Now you can take Edison's | beams at the front. This is accomplished ee ee eons tee, ninage advice and actually learn — : A how to make invention a profession! In _ simple, by cutting slots where the saw is to go and easy-to-understand language, you are told how successful inventors work; you learn how to use the secrets of invention that convert a simple little idea New Book on Inventive Science A wonderful new book has just come from the press that tells all about the Science of Invention; that shows how great inventors work, how little ideas have made fortunes; how you, too, can easily learn the secrets of successful invention. This fascinating Book will be sent free to all those who are genuinely interested. Send for this Book today, as only a limited number are available for free dis- tribution. Write your name and address on the arranging bolts with wingnuts so that the sides of the slits can be pressed against the blade. A small electric motor belted to the grooved wheel provides the power. An Easy Way to Tip Your Favorite Cigarettes Gone smokers prefer tipped cigarettes, but cannot obtain their favorite brand with ends of cork or straw. To tip plain cigarettes at home involves nothing more than dipping the ends for about half an inch Work like magic in emergencies or prove whether your door or padlocks are burglar- proof. Openandtest thousands of dif- ferent locks. Recommended by users in ten different nations. Most wonderful and only keys of their kind. Send $1 today. Novel key chain FREE with set. Master Key Co., 6-0 Manhattan Block, Milwaukee, Wis, ‘ —_ Your Bicycle Into a Motorcycle by using a Steffey Motor Attach- ment. Simplest machine on the coupon gop ted send _—e card hn a in collodion dissolved in ether. When the NG's market. ha any ordinary bi- is no cost or obligation. iis bureau is not connecte ° ° Y cycle. Easi in any way with patent attorneys or manufacturers, | COllodion is hard, punch two or three holes = a Pa We do nothing but teach the science of invention. BUREAU OF INVENTIVE SCIENCE Dept. 23, Wisner Building, Rochester, N. Y. Bureau of Inventive Science, Dept. 23 Wisner Building, Rochester, N. Y. : HIGH GRADE Please send een free book, ‘The Science of In- Cigarettes treated in this manner can W i rq E L E = Ss vention.” literally be chewed without the smallest Head Receivers, Microphones, Keys, Jacks, Ete Oo 2 oS sie DE Ae I, 2 a ge ee particle of tobacco reaching the mouth. ‘MANUFACTURED BY ; nies The tip is practically tasteless and does not 7 ° Dee ee ee ee eee eee errr ee eer eeeer ee eeeeeeeeeeee interfere with the full enjoyment of the NS ge 5 ae SLs ck wee smoke.—G. W. GREENE, Madison, Wis. COMPANY MRTG sob hibhus cs cs Sosee= se tees seensesy °s IT RE. onan through the film at the end of the “‘butt’’ so that the smoke will'draw through easily. Paraffin can also be used, but the collodion is better because it does not crack as readily. fn oly Send stamp for circulars. STEFFEY MFG. CO. Dept. S 5025 Brown St., Phila., Pa. STATE AND 64TH STS., CHICAGO, U. S, A.

Page 111

March, 1923 es RELIEF FOR YOUR TROUBLE ZONE -the nose and throat ok é 4 L -~ MENTHOL COUGH DROPS give quick relief “DON’T SHOUT” “Thear you. Ican hear now as ! wellasanybody. ‘How?’ 4 With THE MORLEY PHONE. I'’vea pairin my ears now, but they are invisible. I would not know ~ | had themin, myself, only that I hear all right.”’ The Morley Phone for the DEAF is to the ears what glasses are to the eyes. Invisible, comfortable, weightless and harmless. thousand sold Anyone can adjust it. Over one hundred THE MORLEY (0.,, Dept. 797, 26 South 15th Street, Philadelphia Write for booklet and testimonials, You Can Save *35.00 By recovering your old auto top frame yourself. lur recovers are custom $4.45 Bere a models of cars. Any person and up that can drive a car can al put Parcels Post Paid it on. We furnish instruc- tions, Roof and quarters are sewed together. with rear curtain, fasteners, welts and tacks complete. Give us the name, ipa! and model number of your car and we will send you cetalog with samples LIBERTY TOP & TIRE CO. Dept. E-8, Cincinnati, O. A Wonderful Opportunity The Eastern Division of the Radio Corpora- tion of America accepts no inexperienced ap- plicants in their services as Wireless Operators other than our graduates. Investigate the advantages offered through taking either our Home Study or Residence course in Radio. RADIO INSTITUTE OF AMERICA, (Formerly Marconi Institute) 328 Broadway, New York City YPEWRITERS We Save You 50 % FREE TRIAL—EASY TERMS | Bi, $93 A ; pERwoos sae ase Le N M eee a ey YOUNG TYPEWRITER CO., Dept. 637, 3 in. cleats, The top is screwed to the % by 3 in. oak strips that form the skirt. The latter are neatly mitered together at the corners. 3 a= > ° . eens: FIG.1 $" CLEATS GREEN BAIZE. COVERING STRETCHED TIGHT & TURNED DOWN INSIDE EDGE ~ 4 ~~ STRIP B Cctamp xi" FIG.2 as $"SOFT WOOD TOP 3'OAK-MAKE BOTH PIECES > THE SAME LENGTH, 30" if The table open and closed, with the dimensions of the various parts The clamp, Fig. 2, is of hard wood, beveled at the ends and long enough to en- gage the bottoms of the upper cross pieces of the legs. A 14-in. stove bolt passes through its center, through a spacer B, and through a 14 by 8 in. piece, A, which is the last to be secured in place. The bolt should have a washer under its head and be riveted slightly at the threaded end after the nut is adjusted. To get the proper ad- justment of the nut, turn the table upside | down with the legs in place and lay the clamping unit in position. It-will then be easy to get the proper thickness for the (Continued on page 126) % Bans ¥ Free THE HOME WORKSHOP NAME Con- Catalog ; strection @ ems | | Folding Table Is Useful for Cards a MAKE THIS FAST CAT BOAT MODEL or Luncheon RS Be the rt oy in your neighborhood to 3) CHAUFFEUR °40 wis ty Cal-boat model “the Snipe. By A. L. Morgan a : e other bo vk ar F you when they see it. this finished r ‘3 P t Y N Pee Sg ge ge Moke substantial than an ordinary u our ame Fer eee, Suifaren 240 folding card-table and practically as ON sq. in. eight 2 Ibs. That : : a = oO . ts tis Y Snipe’? when com convenient to store away, the table illus- THIS y S Here are, the materials trated will be found a useful article for | Men like you are wanted for big-pay posi- ¢ e send you: ° . block, side planks, many purposes. In winter it can be used | ¢j in the fascinating field of bil ack, pide _veasee. ; ions in the fascinating field of automobile Blanka” mast, as a card-table and in summer on the | engineering. We have - utritaamm, | | Veranda or lawn for luncheon. The top | made it easy for you to Price stern piece— cart yourse. or one oO ts can be taken off merely by giving the er these positions. Youdon’t “pecesaary wooden clamp underneath about one] have ¥ go to aan Reduced ‘ spatiale the only eighth of a turn; the legs then fold together | You don’t have to serve . Eee sary bein and the whole can be stored in a corner | 29 apprenticeship. Fif- | Dowm goes the price Seas Ee 0 smoo teen automobile engi- }on these famous Auto them down, of a closet. - peers and 9p Pecialists Beste. a We have and fit them “4 ave compi a spare |induced our printers Complete, Catalog. towether ‘8, Figure 1 shows the complete table and time reading course that [and binders ‘to. cut descriptions, illustra: ced aimee ome print Fig. 2 is a section through the top, which is will equip you to be an the price they r charge ited” wsodele cand: cone Serco a 1 i i automobile expert with- | us. We pass sav- ple me cmc tates eh, = eet pe raven % by 6 in. pieces of soft wood glued ook ae Bn sm e + toe ing on io car aaa ers engine e Postman ress . r an rein- your present work. omers, ODELS BOUCHER LS Madicon polly oa York forced by two 4 by Mail Coupon Now AUTO BOOKS For FREE Trial 6 Volumes Shipped Free| Partial List Now ready for you of Contes an up-to-the-minute six- | More than 190 Blue- volume library on Autos prints of Wiring mobile Engineering, cov- Diagrams ering the construction, | Explosion Motors care and repair of pleas. | Welding . ure cars, motor trucks | Motor Construction and motorcycles. Brim- and Repair ming over with advanced | Carburetors and information on Lighting Settings | Systems, Garage Design Valves, Cooling and Equipment, Welding Lubrication andother repairmethods, | Fly-Wheels Containseverything that | Clutch _ a mechanic or an engi- | Transmission Final Drive Steering Frames Tires neer or motorcyclist or the owner or prospective owner of a motor car ought te anew. basa on insimple language that - . anybody can understand. | Starting and Light- Tastefully bound in } ,ing Systems American Morocco, flex- | Shop acorn ible covers, gold stamp- | Commercial Garage ed, 2,650 pages and 2,100 Design and Equip- illustrations, tables and ment Electrics yy omer! diagrams, A library that cost thou- sands of dollars to com- Storage Batteries Cars and Repair pile but that comes to | Motorcycles you free for 7 days’ ex- Commercial Trucks amination. Glossary Only 10c a Day Not a cent to pay in advance. First you see the books in your own home or shop. Just mail coupon and pay express charges when books arrive. You can read them and study them for seven whole days before you decide whether you want to keep them or not. If you like the books send only $2.80 in seven days and $3 a month until the special in- troductory price of $21.80 has been paid. (Regular price $45.) Send No Money Now Don’t take our word for it. See books _ Cost. There is so much profit in this offer for you, that we urge you to waste not a moment in sending for the books. Put the coupon in the mails to- day. Send no money— just the coupon! American Technical Society, Dept. A-203 Chicago, Ill. AMERICAN TECHNICAL SOCIETY Dept. A-203 Chicago, Ill. Please send me the 6-volume set, Automobile Engi- neering for 7 days’ examination, shipping charges col- lect. If I decide to buy, I will send $2.80 within 7 days and the balance at $3 a month until the $21.80 has been ary" Then you send me a receipt showing that the 45.00 set of books are mine and fully paid for. If I think I can get along without the books after the seven days’ trial, I will return them at your expense. IAG vis onc ccccvesccccecvnscecsoedcesneseeuneaeen Banpleyed bys ..cccccccces cenncqbteceuabaed coeee

Page 112

nn Need wie as RAI LP Ck. Te magi Fests sees ay 4 > cama tare ee te Earle E. Liederman as he is to-day If a Snake Had Brains— He would still be a snake. With his present body he would be forced to continue crawling on his belly. So he would be no better off. Of What Use Is Your Brain? A snake is the lowest and meanest of animal life, while mankind is the highest. Do you make use of your advantages? Your brain is used to direct your body. If you don’t keep the body in fic condition to do its work, you are doomed for failure. How are you using this wonderful struc- ture? Do you neglect it or improve it? Examine Yourself A healthy body is a strong, robust one. Do you arise in the morning full of pep and ambition to get started on the day’s work? Do you have the deep, full chest, the big, mighty arms and the broad back of aREAL HE MAN? Do you have the spring to your step and the bright flash to your eye that means you are bubbling over with vitality? If not you are slipping backward. You are not a real man and you cannot hope for the admiration or respect of others. Awake! Get hold of yourself and make yourself THE MAN YOU WERE MEANT TO BE. 90 Days Will you turn your body over to me for just 90 days? That’s all it takes—and I guarantee to give you a physique to be really proud of. Understand I don’t promise this—I guarantee it. In 30 days I will increase your arm one full inch, and your chest two inches in the same length of time. And then, just watch 'em grow. From then on you will feel the pep in your old backbone. You will start doing things that you never thought possible. You will amaze yourself and friends as well. Do you crave this new life—these new jovs—this abounding health and strength? If you do Send for My New 64-page Book “MUSCULAR DEVELOPMERT” It Is FREE It is chock full of photographs both of myself and my numerous pupils. Also contains a treatise on the human body and what can be done with it. This book is bound to interest you and thrill you. It will be an impetus—an inspiration to every red-blooded man. _ I could easily collect a big price for a book of this kind just as others are now doiag, but I wane every man and boy who is in- terested to just send the attached coupon and the book is his—absolutely free. All I ask is the price of wrapping and postage—10 cents. Remember, this does not obligate you in any way. I want youtohaveit. Soit’s yoursto keep. Nowdon’'t delay one minute. This may be the turning point in your life. Tear off the coupon and mail at once while it is on your mind. ‘ EARLE E. LIEDERMAN Dept. 1303, 305 BROADWAY, NEW YORK CITY — oe oe ee ee ee ee oe oe oe aS A eo a ma EARLE E. LIEDERMAN Dept. 1303, 305 Broadway, New York City Dear Sir:—I enclose herewith 10 cents for which you are to send me without obligation on my part whatever, a copy of your latest book. *‘Muscular Development.” (Please write or print plainly.) ee Popular Science Monthly THE HOME WORKSHOP Substantial Folding Table (Continued from page 125) spacer to allow the clamp to move freely and yet have a slight spring when it grips the cross pieces on the legs. The top is covered with green baize, stretched tightly and tacked at the edge sufficiently to hold it until the oak finishing strips have been secured in place. These should be neatly mitered at the corners. Figure 3 shows the end view of the legs when folded and Fig. 4 the front view. The diagonal braces are not mortised but simply sprung past each other and secured at each end with one screw. One pair of legs is made to fit between the other pair, and the pairs are held together by two bolts, which also should be riveted slightly to keep the nuts from loosening. The woodwork can be finished with a varnish stain of any desired shade or shellacked. ; Reversed Hacksaw Blade Cuts Thin Tubes Cleanly Foe cutting insulating tubes of fiber or mica and thin brass or other light tubes, try using a reversed hacksaw blade. This ean be used in the regular saw frame or provided with a handle shaped from a piece of hardwood and fastened to it with tape or rivets. Light tubes are apt to beshattered when cut in the regular way, but using the reversed blade and a “‘pull’”’ stroke lessens the danger. This method is also useful on heavier pipe when the blade tends to buckle and break.—M. F. A. Mule Racing on Cardboard HE drawings show how to make a new game in which the players each pretend to ride a mule. The rider who first crosses the line at the top of the hill is the winner. Only two can play the game. Two push- pins represent the mules, or the heads cf clothespins with 1-in. brads driven through their centers will serve. Place the mules on MOVE ONLY ONE HOLE AT A TIME MULE O ; MARBLE . Es, £& CENTER CHUTE RIGHT CHUTE AHEAD |} BACK : REVERSE FOR LEFT This simply made game gives the children endless amusement the bottom holes. The first player then lets the marble roll down the chute and moves his mule according t. the direction taken by the marble. The second player does likewise, and so on until the hilltop goal is reached. Make the base of one piece of heavy card- board 14 in. wide and 26 in. long. Cut out the three chutes from thinner cardboard and glue them in position.—D. W. CLARK. apes Vif la Y Creel \ SS SQN vie GTS Noo a b Montgomery No Money Down While other watch dealers are raising their prices, asking you for larger monthly payments, and mak- ing payment terms harder for you to meet, we are offering you our new model Santa Fe Special, no ad- vance in price, no money down, easier terms and smaller monthly payments. WE realize the war is over and in order to double our business we MUST give you pre war inducements, better prices, easier terms and smaller payments. Adjusted to Positions Adjusted to Temperature Adjusted to Isochronism Adjusted to the Second Thin Model. All Sizes. Without one penny of advance payment let us place in your hands to see, to examine, to inspect, to ad- mire, taapprove, a real masterpiece in watch creation. A Watch which passes the most rigid inspection and measures up to the exacting requirements of the gre:t Santa Fe Railway System, and other great American trunk lines. Page 12 of Our Watch Book is of Special Interest to You Ask for our Watch Book free—then select the Watch you would like to see, either the famous Santa Fe Special or the 6 position Bunn Special, and let us ex- plain our easy payment plan and send the watch express prepaid for you to examine. No Money Down. Remember—No money down—easy payments buys a master timepiece—a 21 Jewel guaranteed for a life- time at about half the price you pay for a smaller — of other makes. No money down—a wonder offer. SANTA FE WATCH COMPANY 380 Thomas Bldg., Topeka, Kansas (Home of the Great Santa Fe Railway) sai Rstter; bast Card or this Coupon Wil Bring My SANTA FE WATCH CoO., 380 Thomas Bldg., Topeka, Kansas Please send me your New Watch Book with the understanding that this request does not obligate me in any way. Meyer Both Company, the largest Commercial Art Organization in the World. offers you an unusual oppo ity. for evelop your tal a Vi practical training, If you liketo drawd eu lent. tudy this practical course—taught by t ionally known Meyer Both Company, with twenty-t' oF rs suc- cess—who each year produces and sells to advertisers over 15,000 commercia arewings. Our teachers give you the double ativantage of being in- structors of proven ability, as well as artists in this widely known organization. Meyer Both instruction is the difference between successful factand experimental theory . Commercial Art is a highly paid; intensely interesting protoe equally open to men and women. Home stud ction. Get Facts Before You Enroll in any School. Ask the Advertising Manager of theleading newspapers in your city, anywhere in S ‘the United Engl tates; Canada, and or Australia about the Meyer Both Company—let them tell you aboutus. Write for our illustrated book ‘YOUR ©PPORTUNITY”’—for one-half the cost of mailing—four centsin stamps. MEYER BOTH COMPANY Department of Art Instruction Michigan Ave. at 20th St., Dept.35 CHICAGO, ILL, NOTE—To Art and Engraving Firms: Secure practical artists among our graduates. Write u

Page 113

March, 1925 127 \X ° i \ Factory Executives Needed THE HOME WORKSHOP Aa up-to-the te A Bi . Radio Course. Wire- \ t Big Salaries Old Bicycle Pump Forms ie a chee its Employers are having a hard job findin ° atest development. ~ Jrite an as OW SOCUER cla he Pip dof men to Bi Pannen ee Sane you can get this $45. 0e: cence tay duction departments. THE DEMAND PAR pay BiG SALARIES ana oneramintet | WYNN EeY ata closer aten got an opportunities for — ADVANCEMENT . matic door closer when you can we diough our ‘complete course fa “Modern make one yourself? The main part of this the SPECIAL TRAINING teauired—~ be oteante Ye homemade door check is an old bicycle is your own home—during spare hours at a very low cost. pump. ; raining is under supervision of leading practical fac- . . tory experts—and you are most sure to enjoy the entire The cylinder is cut off at the lower end courtiey will tick,” Principles you are after ina / and plugged up with a round piece of brass 3 9 DUCTION. MAN if’ you rant more CONGENIAL which has a projection through which a the cloas where YOU Benne eat ro fa _ is — to take a bolt. This projec- waWrite today for a copy of our FREE BOOK:— ton is held between two angles bent up | (Forging To The Front,” It outlines & definite method from flat iron and screwed to the frame GER a. Send today! Don't wait! . above the door about 1 ft. from the hinged LINCOLN EXTENSION UNIVERSITY, Inc. side. A loosely wound spring is inserted = 57¢ Kirby Building, - - Cleveland, Ohio around the ~ sli in the pi and the Quesansessssse7, -_ —_ - The — rod - 5 , ent into a loop to accommodate a roun tos [ N > piece of iron. This rod is bent in such a their = oS be sent anyone book. = W ee = ESCAPE . a : Electricity ik: ge ire ¢ d - e : i: as ao * Got Pence a is VILLI LIAN AY ck : ad bia competition; a glance at the prices below will convince you t the World Battery is the best raemaiiPiee_ | Se HaE 1000 Raise mobile Prices q re G Volt. 12 Plate - $12.80] fly. Express C. 0. D- 1 Ford, Chev., Mitchell, Hup., Cen Dew ge “ Grant, Elgin, Velie, Saxon. battery service at half , ; ; § Von. £5 Prete - 940,50) cot. aoe wee IRON ROD W. E. Pence of Chehalis, Washington, one ” Hudson, ‘Nash, Stude:, Dort. RADIO PRICES of my students jumped from $30 a week to . £2 Vou. 7 cue 18.00 It. $750 a month in one year’s time, through vc i SY ssp my home-study course in Practical Elec- we tricity. One year ago he was an ordinary | Thed 1 in vl sti tnt mechanic. Now he runs his own business. PER DAY a He gives my course all the credit for his « success. ve & AN D UP way as to engage the loop at one end and Wh t’ y ? 7 | ats lour ruture: h Selli: trated, holi 7 pee oem ere ey ge fasten to the door at the other end, which Todas you see cons Sea denle a in collapsible tubes. Ten_times | is flattened and drilled for screw holes. . .- the strength of bottled flavors. ° , to $35 a week. In the same six days as an a Gustentasl endes G, 0, sane Sead The piece of brass in the end of the . “ Sane. AM Eewcmn, ale te eneue : : : Electrical Expert you can make $70 to $200 , home. Used every day. Not sold |p cylinder has a series of holes drilled | and make it easier—not work half so hard. . aoe Big repeat- Pa through it near the edge to admit air. Why stick to a low-pay, no future job when you can Men or Women Covering these holes on the inside is a steel get three to ten times as ’ can make big money, Haut sold : : a much in the most fascinating gree gry J disk ne —_ on a machine screw. At Electrical } work in the world? asure repeater. Must satisfy the top of the cylinder is soldered a piece of E . customers or money back, a Agia pi EF "ea Be tubing, threaded on the inside to hold a | — $30 ee Help line of cus Ge i : repeat orders every month setscrew. The sgetscrew is ground as shown Oo toa Gapersee tocome. wieK in the detail drawing. A small hole is | a Day P AY b a5 bee Eeotate te. watt =| drilled in the cylinder as a seat for the | | Right now, trained BIG Jo } —— — a — another in the tubing | frical Experts — are Nosnaner whet Matet work | NEW SINGLE PHASE A. C. MOTORS| | 2¢@r the lower end. |] the highest salaries. | a big pay job in a few short = : é EMERSON When the door is opened, the steel disk More big jobs are § months. Age or education a 4% H. P.—110 ; ° | open than there are | make no difference. Myspare : on 60 eycle, 34 HP. $61.00 is pulled away from the inlet holes by the | men to fill them. | time home study course in complete with HP. 67.59 air that is sucked intothe cylinder. Asthe | | electrician pets big preracel Ree AL renin o paboma 114 HP. 85.00 plunger travels along the cylinder, it com- | fiea’ ibang ah Rl ’ ley - ~ $13.00 2 HP. 97.00 presses the spring. When the door is left | | Kind of men tai Money Back —— — may ty ee open, the spring pushes the plunger back Get ready for one of G t Complete with on IE YEAR Hforbay Voit eo: and the air forces the steel disk against the =o g0 into business a uaran sad Dulley i “3 7 ; ; or yourseir. our success is assured Satisfaction guaranteed or money refunded inlets. The air then is expelled only through show you the way. [| under bond I guarantee to Illustrated Catalog of Motors and Supplies FREE the escape valve. By adjusting this valve, nent atin eae penny you pay : : ee ee oreo eee 2, OOCNEO the door can be made to close quickly or tion. "A million dollar institution backs up this . slowly, as may be desired. guarantee. . MOTORCYCLE BARGAINS If the plunger is well lubricated with - SAVE 25% to 65% heavy oil, the door closer will be found to Send Coupon NOW 4 on Slightly used and Rebuilt Motor- give very satisfactory service.—EDWIN G. f 6Vi ] F 99 °. ly Ts, e 3 Wheels, Evans Power Cycles, Bicycles. GETTINS, Los Angeles, Calif. or ita acts Send for Free Bargain Bulletin and ; Be a n . pom yt neonthas in used, eal ae : e a we divre ts pando, Mig Rp dilg Sag oP ees 4 new machines,supplies, accessories, etc. ~ f Links from Sash Chain Make fiandreds of other a. — into the big pay class. a AMERICAN MOTOR CYCLE CO * SEN JPO! . n nn g Dept. 315, 2047 W. Chicago Ave., CHICAGO Neat Terminal Connectors L. L. COOKE, Chief Engineer e : : . ; Your Own EAT terminal connectors can be made Chicago Engineering Works Print | N from an old sash chain. Cut off alink, | Dept. 533, 2150 Lawrence Avenue, Chicago, IIl- = SS | rs, | ; : : », OUT aN . —* -” — it out. Then cut one “2 COOKE, Chie En incr odes / q HICA : foryears, Hasy toute at | shown and bend the’ PIECE yy LINK | ae 533, 2150 Lawrence Ave., Chicago, III. | es sent. v ae e BiG PuOWTT. Writetactorr other end around the CUT roy | Uw itet eh etl actcrigelon of your free outic and TYPE, cards, paper,envelopes, | bared terminal of OFF CHAIN | ae peace, Ses employment service and let- | THE PRESS CO., D-33, Meriden, Conn. the wire, soldering BENT. OPENED : | . x | the connection =, OUT ii | 25.00 in Prizes thoroughly. — yoo wire | 4 FRANK HARAZIM. y Address , See page 6 in front of book for full details Mareh. 19293

Page 114

UNDERWOOD Yes, only $3 down puts this genuine standard Shipman -Ward Rebuilt Under- wood in your home. Then—small monthly ayments, or if convenient, py cash. ither way you get the world’s standard typewriter at a big cash saving. WHY PAY RENTAL? Think of it! You pay little more than rental, and the machine is yours! We offer the same chree models of the Underw Typewriter which are being made and sold by the Underwood Company today. The only difference is that Shipman-Ward machines are priced lower and are rebuilt like new by experts. You can’t tell them from brand new machines. Visible —- —the FULL LINE of typewriting is visible at a times. STANDARD 4-ROW SINGLE SHIFT KEY- BOARD. Two color ribbon, back spacer, stencil de- vice, automatic ribbon reverse, tabulator, etc. TEN DAYS’ FREE TRIAL See for yourself! Try the typewriter ten days, You must be satisfied or the entire trans- action won’t cost you a penny. Act today Get our. pee petrates catalog and full particulars. Write NOW. ===FREE TRIAL COUPON«== Typewriter Emporium SHIPMAN-WARD MFG.CO, '2143 Shipman Bldg., CHICAGO

Law Course in Book Form 13 Vols. Bound in Law Buckram. Compiled by 56 of America’s Most Eminent Legal Authorities Here is a complete home-study law course in book form that you can master in your spare time. Thirteen volumes, nearly 6,000 pages (7 x 10 inches), bound in law'buckram, red and black labels with titles in gold. This wonderful law course is the combined work of professors of Harvard, Yale, Pennsylvania, Michigan and Wisconsin law schools. Study at Home, Aided by Free Reading Course Every principle of law is made clear. Fascinating reading course of 25 Texts (free with the books) is a teacher, right at your elbow! A set of review question covers the text matter fully. You get the entire 13-volume law 75¢ a Week library and Complete Reading Course of 25 pamphlets for only 75 cents a week. See offer in coupon.

from Eye of Ax fas the handle of an ax, hatchet or hammer breaks short, so that a tightly wedged piece of wood is left within the tool, the eye can be cleared by using an alcohol lamp or bunsen burner as shown. A gentle but continuous blast is blown through a blowpipe so that the intense heat

Blast from blowpipe burns hole through tightly wedged wood

128 Popular Science Monthly Mar — THE HOME WORKSHOP . ca € Miniature Tool Holder Increases . Scope of Small Lathe \ ew usefulness of a small lathe used by the writer for model work was limited by the fact that the tool holder of the slide A 4 i ‘h F ’ ti n rest provides for only two tool positions— ts e ascina 10 one at right angles to the bed and the other ee S parallel with it, and there was no provision ie of the tars for altering the . = height of thetool. |[™ ATURN with its rings, Mars with its canals, the M 8 : do 1 cae Ti eee: ost of the in- craters of the moon, the much-talked of sun spots- ? th you can actually see and study all these wonders with convenience re- wi sulting from this a Bausch & Lomb Telescopes arrangement was i — : overcome by Bausch & Lomb Telescopes, made by America s leading making a small fic lens-makers, are scientifically accurate, well built and beau- ol tlie an in tifully finished. They are made in ranges of power from ieeaheadadl ’ 24x to 120x, and equipped for both terrestrial and astro- iuustrated, = RIC POLES IR lo! nomical observation. Country clubs, yacht clubs, schools ; A piece of 3%- on bench lathe th and homes become observatories when equipped with one in. square cold - of these beautiful instruments. rolled steel was put in the lathe and 2 in. of li Write for literature on these new telescopes— its length turned down to 1/4 in., this being | fa See them at your dealer’s. the size of the regular tools. Half an inch | th from the shoulder the bar was cut off, leav- | ye BAUSCH & LOMB OPTICAL Co. ing a piece 2% in. long, with 14 in. square | b 600 St. Paul St., Rochester, N. Y. and the rest round. Through the square | T New York Washington Chicago San Francisco London part a 1%-in. hole was drilled at an angle th | for the cutters, and a hacksaw cut was run | - from the end of the | Pe Fe? acetone ane aan square part tomeet | | 25.00 in Prizes the hole. Lastly, a | & in rizes ¢ hole for a pinching | t screw was drilled | L See page 6 in front of book for full details 1,000 good positions open in splendid territory. beyond the tool } h oa Our salesmen make big money selling Fyr- Fyters to hole, enlarged to | homes, auto owners, garages, factories, hotels and ’ g t) schools. Cash or easy payment. We want only fast, clear the screw | hard workers, Wetrain you Free if you have no exper- ‘ | | jonce. —— to learn. eony to sett ona make $2 ) to EER RES above thesplit and | | 4 Rial wade $9 first wack with no previous sell. | The tools are made of tapped below the . ing experience. Others made from $35 per week to 1/8-in. drill rod cut | 8 ene «lien gop sailhalageed gy Re Tool d oe | 8 te work we will put youin the way of making more ools were made of 7g-in. drill rod, filed jv money we Cte cg mee atid to shape, hardened and tempered to a light | ¢ toa - wt "| straw color and finished on an oilstone. In t TAP DRILL SIZES spite of their smallness, the cutters have + : : ¢ we This New Handy Time Saver Disc of stood ~~ well and eee no trouble what- | i t fs “aa screw threads and tap drill sizes will auto- | ever. This little device has very greatly in- | 1 drill tobe used when using any kind of a tap, The creased the usefulness of the lathe and has | ky Jj Sesiaiite iilnc=falnesag-astes proved excellent for inside work, such as ; = 7 Srciate reer ter site g.completenbiest | boring.—H. G. * Be Priated on the very best pressed _fibre size 3 44 { A inches with printed instructions, Two for 2Sc- ie $ . ae Agents wanted. { > ROGERS CO.. 3101 Lyndale S, Mi lis, Mi & et brings genuine secs _e | Flame Removes Broken Handle ? 8 : : a neentrat oint will soon burn a g Send by return mail Bargain Offer No.\2143 g American Technical Society, Dept. E-203, Chicage, U.S.A, | COnCentrated at a p é ote Standard Visible Wenig Underwood. 2 Please send ‘*Library of American Law and Practice” ang | hole through the wedged fragment of the is is not an order and does not obligate Reading C f. days’ ination, shippi E ; : 8 ine to bu ; charges collect. I will send @2 80 within sever days ard sao | Handle. With this hole as a starting point, | . me y f “ ° e . | t ’ (laa rere | OS the work of but a few minutes to re- g Name....--..-...+.- Pezeee eres seer? : ' move the charred pieces remaining in the | H Seestor B.F.D.No.... «- ny . a a

Page 115

aly

March, 1923 129

THE HOME WORKSHOP

—_—_— Simply Made Weather Telltale Gives Warning of Storms By E. A. McCann Fg tgpedad oa this apparatus must not be considered as a really scientific in- strument, it is easily made and as a rule will give warning of fine or wet weather, storm or calm. First, get a glass jar, C (a milk bottle will do), and a flask, B, from the drugstore; then, to fit them, build a framework, A, which is just an incomplete box, with back, top, bottom, sides, and a partial front. The instrument may be entirely inclosed if suf- ficient openings are left for the air to get in and out freely. A piece of brass tubing, F, about 314 in. long, fits a socket in the back and goes through the front. Plug the front end with a piece of wood and into the plug screw a light pointer, J. To the back of the plug fasten a piece of catgut, which runs right through the tube and out at the

Now, hang the flask B in a wire sling and fasten a silk thread to the wire. Runthe. thread over the pulley, hanging a weight, D, on ee the other end, a little less than The telltale with one side heavy enough to removed to show con- balance the flask struction when partly full of water. You can adjust this later on when the flask is inverted. Make a dial with ‘‘Fair’’ on one side and ‘‘Wet”’ on the other, and fasten it-to the front of the box. Fill the jar or bottle about a third full of back, as at G. ; E Thread the tube yoy F through the front *\vs | OER | onal and fasten the ies pulley, E, tightly , to the tube so that t D it is over the cen- H SILK ter of the jar. i N — Leave the gut i! hanging loose for i the present. i ~A ti iw

m po \ , “mn SS Radiola Grand and Mahogany Stand with “B”’ Batteries, tubes and full in- structions. ..$350.00

This symbol of quality is your protection Sales Department: Suite 2080, 233 Broadway New York

Two Supreme Achievements in RADIOLAS

Radiola IV, complete with 4 tubes (1 spare), all batteries, headset with telephone plug, and silk covered leads for . ‘ J antenna and ground. .$275.00 show you the Radiola line. Radio creCorporation RADIOLA Grand The finest: principles of radio detection, amplification and loud speaking are embodied in the new Radiola Grand. The Radiola Grand has _ been especially designed to receive broad- casting stations operating on the standard wave lengths of 360 and 400 meters, but an additional range is available up to 550 meters. By means of a new type of loud speak- er, the entire family may receive broadcasted music and other enter- tainment and instruction. A telephone jack is provided in order that head telephones may be employed for the reception of broadcasting over great distances, RADIOLA IV Radiola IV is a self-contained console- type broadcast receiver. The cabinet con- tains a regenerative receiver, a detector, two stages of audio frequency amplification, a new loud speaker of unsurpassed tone quality and all necessary batteries. Radiola IV is not only a highiy efficient receiver, embodying the latest developments in design, but is also a thing of beauty that will grace a drawing room or library. Both of these Radiolas provide exceptional long-distance as well as local reception. Ask your nearest dealer to

America

District Offices: 10 So. LaSalle Street 433 California Street Chicago, Il. San Francisco, Cal.

$25.00 in a a IZ i = si * ‘all hrs,

Assistant’s Course for Women. DENTISTRY

». taAaan

MECHANICAL DENTISTS EARN 7200 ©°450 per moth A high grade, fascinating, dignified. and profitable profession. perience or entrance requirements necessary. No license required. Big demand everywhere. Special Dentist Earn While You Learn in America’s Greatest Practical School Individual instruction by modern up-to-date methods in America’s best equipped Dental Labo- ratory and Clinic. Write for Free Trial Scholar- ship and Free Life Scholarship offer. Learn how easy it is to fit yourself for this big pay profession by the famous National Learn-by-Doing Method. Send For Free Book ‘* Mechanical Dentistry and Its Art” Today. NATIONAL SCHOOL OF MECHANICAL fa» Agents $75.00 Weekly Amazing new seller. JIFFY JEANS (not an overall) protects clothes while working around auto, shop, or home. On and off in 5 seconds. Can- not streak dirt or mud from shoes to clothes when putting on. Kept firmly in place by flex- ible steel bands. Will not wrinkle clothes. Made of high grade Ducking. One size fits everyone. Easily laun- dered. 1507, PROFIT Selllike hot cakes. Just show and sale is made. Nothing else like_ it. low price. Make $75.00 weekly easily. Write today for liberal Agency Proposition.

No ex-

Dept. 33, 506 SO. WABASH AVE., CHICAGO, ILLINOIS JIFFY JEANS, 223 W. Marquettc 24., Dept. D, Chicago, ti,

Page 116

ob lanl GeO ob ea RATE CO a ati i ee i i : Tees W.LDOUGLAS $3 $6758 &§9 SHOES ax wot WwW. L. Douglas shoes are actually demanded year after year by more people than any other shoe in the world W. L. Douglas has been making surpassing] BECAUSE good shoes for forty-six years. This pcs wand of nearly half a century in making shoes suitable for Men and Women in all walks of life should mean some- thing to you when you need shoes and are looking for the best shoe values for your money. shoes in style, quali material and W.L. DOUGLAS workmanship ‘are son dl than ever be- fore; only by examining them can you appreciate their superior qualities. No Matter Where You Live shoe dealers can supply you with W. L. Douglas shoes. If not convenient to call at one of our 110 stores in the large cities, ask your shoe dealer for W.L. Douglas shoes, Protection against unreasonable profits is guaranteed by the name and price stamped on the sole of every pair before the shoes leave the factory. Refuse sub- stitutes. The prices are the same everywhere. If not for sale in your vicinity, write for catalog. Uy, A TO MERCHANTS: If no dealer in your town handles W. L. Douglas shoes, write = ad for exclusive rights to handle this quic selling, quick turn-over line. President W.L. pangs Shoe Co, 124 Spark St. Brockton,Mass, BOYS SHOES $4.50 & $5.00 Popular Science Monthly INTERNATIO Direct from Factory. FOR FORD—Prices from $27.85 up. Factory to consumer direct—Pay only One Profit INTERNATIONAL BODY WORKS, 914 W.Ohio St., Dept. 8, Chicago, III. NAL CATALOG Our net price list. Full line of auto bodies and accesso- ries for Fords at Wholesale Prices. Save . big money on bodi:s by buying A Complete Machine Shop At a Low Price ERE’S a tool that enables you to have a complete machine shop right in your home, It’s the powerful, compact Jones Electric Hand Drill, selling at the low price of $25. This drill can be clamped to a bench and used for grinding, polishing, buffing, sawing, or milling, by using the attachments shown below. These attachments are sold at a slight additional cost. It is equipped with a universal high speed motor. Ventilating features eliminate heating. It is fitted with a Jacobs chuck. Will drill thru the toughest materia!s up to 14 inch in diameter. f A Drill Press for $45:00 For those who want an automatic bench drill press no tool can be found superior to the Jones for the little money asked. In capacity and general construction it is the same as the hand drill described You owe it to your home, your loved ones, yourself! Protection!! A beautiful little btue steel automatic 43% in. long by 3% in. high. above. Write today for further in- man. Absolutely safe. Substantial .32 cal. mil- itary model 6} in. long by 4% in. high. Shoots ten shots—any stand- ard automatic ammunition. JONES DRILL & SPECIALTY CORP. 245 Seventh Ave., New York ship throughout. ABSOL materials! money at once. unless you wish. by return mail. arrival, Dept. 133 Terminal Bldg., = SE Cas ww formation relative to these tools. Holds seven .25 cal. for 25 caliber bullets—any standard 1 Shot Aulomatic automatic ammunition. Agents Wanted An idea! gun for a wo- 1 oO “ 6 Oo 10 Shot Automatic Including Cxtra Magazine. Both models are exceptionally fine guns that usually retail from $15 and $25 up. finest quality forged steel and expert workman- UTELY GUAR- ANTEED against defective workmanship and If you are not entirely satisfied, return within ten days and we will return your 25 for 32 caliber THE HOME WORKSHOP a Simply Made Weather Telltale (Continued from page 129) southerly winds, with rain, especially if the clouds are from the same direction. You will get longer notice of a southerly than of a northerly wind. If the air is dry, but still it falls, expect snow in winter. If it rises, expect northerly winds and finer weather. The quicker it rises, the more wind you may expect. If the wind is in the south and it rises, expect fine weather. The slower it rises or falls, the longer will the coming weather last, and vice versa. If it stops high and steady, expect dry, fine weather; the more it jumps about, the more unsettled the weather will be. A sud- den rise is as likely to bring a storm asa sudden fall. But you will learn most by watching it and the clouds, which are great weather prophets to one who knows how to read them. A Window Flower Garden CONVENIENT and decorative win- +. dow garden may be made by attaching a ledge or board to the lower sash. The board must be as long as the glass is wide, and about 4 or 5 in. wide. A tiny railing on three sides is made from strips of wood about 3, by °¢ in. and heavy wire. Two other wires about 10 in. long are attached to the board at the ends and to This neat flower pot holder is attached directly to the lower sash the sash to serve as braces and hold the stand in a horizontal position. A screw through the shelf down into the lower sash rail will hold the stand in position and prevent it from being accidentally dis- lodged. When the lower sash is opened, the plants rise with it, thus allowing the unobstructed circulation of air.—B. E. One Nail Holds Corner Piece Y CUTTING out ‘‘dustless’’ corner pieces as shown, they can be fastened in place in stair corners and in the corners of rooms where they are needed with one nail apiece. Driving the nail slantwise into the corner draws in the center of the triangular piece firmly and makes a neat, The very SEND NO MONEY Write clearly your name, address and model you wish and we will ship You pay the postman upon Write for our new firearms catalog. California Trading Company Los Angeles quick method of fastening as shown here. . When I re- quire a supply of these corner pieces, I simply cut them from Sse scrap tin and ehh paint them.— JOHN R. DODGE, y 7 Normal, Ill. IN CORNER an¢ se pe pi an

Page 117

nthly March, 1923 131

a | THE HOME WORKSHOP : , A le ‘ _ ents Rig Makes Light Work of Drilling 6 and Boring by Hand | # | the By Henry S. Laraby You a HENEVER heavy drilling or boring rio is to be done in the home workshop Catalo gue th ry and no machine is available, much labor es may be saved by constructing a drill rig like oan the one illustrated. It is easily adjusted, ower has few parts, is very strong, and takes up ming no room when not in use. Either a One copy of this complete Catalogue of dry regular hand brace Radio Outfits, parts, Dictionary of Radio | the can be used in Terms, Instruction Book, and Guide to : connection with it, Successful Radio Work—one copy is psig or a brace may be yours Free, as a Simpl i d and Pa forged from a %- spaces on rach a ae we t by . will mail the complete book to you Free, yreat a od. is ob by return mail, : yw to ae | a _ It quotes the lowest prices, amaz- tained by means ingly low prices on everything for the of a lever of oak expert and the amateur. Every im- or other hard proved part, the most up-to-date out- wood, 40 in. long. fits, gdm, that is —— - the The fixed end is most modcrn type—at the lowest win- ossible prices. ‘hin fastened to a wall ae . It gives ote of broadcasting stations, and Hing stud or a “two by four” at the back of gives much information about radio construc- The the bench by means of a block, yoke, and : oe ene ee Lene son eee —_ wedge, which are adjustable as to height. a, a HIN g The block has a lug, which engages a hole Parts ° ” ’ ‘ rts wood in the end of the lever and in the under F J Why Pay Higher Prices ? side of the lever is a bearing for the brace. ; f Montgomery Ward & Co. has for fifty years dealt on a Ae Ample adjustment is provided for boring \B\4\= Ti Sse Ene bao shesbeele svernee, overs id to work of various sizes because the holes for te" a higher prices elsewhere? Write today for this Free Radio the yoke are 4 in. apart and the wedge per- :\ snl ‘Ghaaepy epee Van. Yon sahil ee oats mits any adjustment within 4 in. A saw- Dictionary} E.- \ = Large card, of Radio {| E: election of | Write to the house nearest you. Address Dept. 5-R FLAT 5P Terms ; Outfits — Chicago Kansas City St. Paul Fort Worth Portland, Ore, RING : — 1{ ON. EACH SIDE le 5° |

SS

» |

2—>1\ OF WEDGE ay = | =fT PM MY, + |.' &% OAK eS f, y m 1% 2°THICK , i =The Oldest Mail Order House is Today the Most Progressive = SAARINEN BIE RL ~ sessss S \ \ | j

Hy

y ee. Lip, wth 4, Z one MM LL A m a t u 7 \RON ROD $x3" PROVECTS 1" P > eur t | * Agents Wanted a \ A || to sell high-class radio sets and parts (€ . full or spare time. Liberal commission. N Ui - K ZA’ ROD’ 5 C ies {no TORE BET TER OR atalog crew . Fr ee ‘sash i — ot) Make mon- and Bp ey by selling dis- Bx42'BOLT ano 4 WASHERS ¥ your friends SPRING HOLOS and _neigh- } : oned, hey ates | Save 25% on this solid gold, genuine diamond ring. “er ee Pi FROM FALLING} dy possi | Read this—the most pond. aes free trial offer ever made. > 6 MYLES 4 z a iid DISK FOR BEARING YOKE ment at 0 Money Down—No €.0.D. . po eas fe Sto) WRENCH mw prices Mail the coupon below — don’t enc! @ penny — and a _ iM, ; ON BOLT that will we’llsend you either the man’s or lady’s ring shown above if a + uT This save them on trial, all charges pfepaid. Pay nothing when the ring ce | : ¥ a E i molded arrives—no C. 0. D. wear it a week—then decide. If you oR FIT BRACE fN LEVER | | ! aes of at our expense and that ends the matter. If you decide orner SCREWED ON Elena ee ter is one complete $5 50 to buy, send $3.75 after trial, and pay $3.75 a month antil sae ATTACHMENT BRACE FORGED | our splendid values— only... ° our special cut price of $38.75 is paid. (Over 10 ened $xf' 8055 To HOLD ReG- POF gon, FoR |! Y] 2a" itn Dette © ti pap yy eo rr U f UARE SHANK |i, WA ac ng is so gold, exquis mi e : rners LAR BRACE as lene Colum 1a Kadio Corporation graved and beaded, The 48K white gold top is set with. eed tose! ) 2757 Diversey Avenue, Chicago an extra brilliant, blue white, perfectly cut, top quality . / | genuine diamond. (Regular $50.00 value—neow on! dion shall i] $38.75). You risk nothing on this wonderfal offer ¢ the SUES ET ISS |, Mail coupon today! Be sure to state finger size. me VEN VOCE nao am ial is LOUpON “4 How the parts of the heavy boring rig | chman Co., 224, 5°. Peoria: Street re- ; are made and assembled Harold La an *9 Dept. 1763 Chicago, til. Send me free of all charges the solid gold, uine diamond ipply ring checked below, for a week’s free trial. 1 enclose no mone eK pay methine on arciveic = ene oa = j one = I - 1 ° e er return e ou r 8 m orner horse can be used in place of the bench. In e e payment of $3.75, an then $3.75 on the first of cach month until ] % 23 your Cut price of $38.75 has been paid. Title remains with you mply fact, if the 14-in. holes in the stud are run eek 8 pe op z ' y’s Ring 5 P A4450. from from the floor up at 4-in. intervals, any You can earn $15 to $50 week writing show dai . * ° cards in your own home.—No canvassing.— and working height may be obtained. In opera- Jeasant profitable profession easi ‘and quickly ee (niivcannimeiieeteuniiniiaiaied inidiieel : > ead o . - e m. tion, the lever is pressed down undey the Ramatis clio nok cteemant- Wetene _— Home Address...+..... Ctiutittieamuaniada ; DGE, left arm and the right arm is used to turn Oneet. Fal partieuareand tockieb ies i chcciaaneniagieaniiie State...esseees cutie : the brace. WILSON METHODS LIMITED— DEPT. © ; / & 64 East‘Richmond, Toronto, Canada. | ON scccensbessecuankies ONO 5. cicccneccanimameaie a , | qsnsse Copyright 1922, Harold Lachman Co. s:isauntecnnssecnsenssseeab

Page 118

co

Se Ey ae Nm, ae ig ae nies eS SSS Sy a ee

Se NE RGR AT AERIS OE

ADEM ROLE NS yh ehe sting Peseta Acrdii ~ Pi parr pA yc Big tae Btn sh A og ma = ‘ersone residing in Canada should send this coupon to th International Correspondence Schools Canadian, Limited, Montreal, Canada.

FREE Radio Catalog ) Our big stock of standard * makes of radio sets, parts and supplies, fully illus- trated, Play safe — buy standard equipment froma reliable house. We ship from stock. Send $6.50 for genuine Westinghouse WD-11 ‘peanut’ tube—no storage battery needed. 60 cents extra for socket. Wonderful results. JULIUS ANDRAE & SONS CO. in business since 1260 119 Michigan Street - Milwaukee, Wis.

LAR sE MANUFACTURER OF SHIRTS wants Agents to sell complete line of shirts direct to wearer. Exclusive patterns. Big values. No capital or experience required. Write for free samples. MADISON SHIRT MILLS 507 Broadway, New York, N. Y.

The Shipshape Home How to Do the Odd Jobs

; ALTHOUGH the difficulty P apering of papering ceilings is Ceilings what deters many home workers from doing their own paperhanging, it is not really hard to do, and if the proper system is followed, an amateur can quickly learn to paper ceilings as deftly as a pro- fessional. A plank, or two planks, long enough to reach from one wall to the wall opposite must be provided. It should be raised on tables or other supports so that the ceiling can be reached comfortably with the palms of your hands. A paperhanger’s smoothing brush, or a clean whiskbroom, and a photographic roller are necessary, although a caster will take the place of the latter for rolling seams. You wil! also need what I cal! a “little | helper.”” This is made by nailing two | wooden strips about 4 ft. long inside the

} }

| i ; ae | } Fr | <a | | | i |

ends of a soapbex, as shown. A piece of | lath is nailed across the:top and on this is | fastened a heavy sheet of pasteboard about -1 by 2 ft. This makes a light but firm stand. | After removing both selvage edges, cut | the paper about 6 in. longer than the room | is wide or long, depending upon which way | the paper is to run. It is best always to | have the seams run toward the light. Cut | 5 or 6 lengths at a time and spread them, | printed side down, one over the other on the kitchen table or whatever is to be used | as a pasting table. Place the paper about | 2 in. from the edge of the table, loosen the top strip, draw it toward you until the nearest edge is even with the edge of the pasting table, and apply paste for about 8 ft. from one end, brushing the edges out- wardly. Double the paper about 1)4 ft. from the end and fold the pasted surfaces together, taking care that the edges match on both sides, as shown at 1. Pull the strip along until you have an unpasted length on | the pasting table and apply paste to an- other 3-ft. length. Lift the paper at the | place where the end has been folded over the pasted surface and fold over the newly pasted section, as shown at 2. Repeat this process until the entire strip is pasted and folded as at 3. Place the pile of paper on the little helper in such a position that when you take up

(Continued on page 133)

the beginning of the strip the pasted side | Popular Science Monthly ID you know that you can get Regenerative sets at reasonable price in RadioCraft’s D-4, with the D-5 2-Step Amplifier? These fine sets are made of De Forest parts—and carried by De Forest dealers. See them!

THE RADIOCRAFT CO., INc. 139 Franklin St., Jersey City, N. J.

AGENTS 27475 Looks Like $5.00 Worth Gives You $1 Profit

$12 an Hour! First Day Out W. H. Marion, a beginner, made 36 sales in three hours, first day, $36 profit! How? Our represen- tatives introduce our products with a fist sale of beautiful combination sets of Toilet Articles, Soaps, etc. You sell at half store prices—no fancy talk— sell on sight. Make 20 to 30 sales a day with DOLLAR profit on each. Easy to average $100 a week. Could you ask more while introducing line, establishing a permanent business for yourself? Another plan calls for no deliveries, no investment, no delays. You bank quick profits. Also winning premium plan. Write quick for full details. EE: No contest. Every producer * gets a Ford Car absolutely free. Most amazing offerever made. Jon’t waste a minute. Get letter into mails right now! : E. M. DAVIS COMPANY Dept. 5703 Chicago

Stop Using a Truss STUART'S” PLAPAO- PADS are different from the truss, being mechanico- chemico applicators made self-adhesive purposely to hold the distended muscles securely in place. No straps, buckles or spring attached —cannot slip, so cannot chafe or press against the pubic bone. Thousands have successfully treated them- F educed = <clyves at home without Reduced ac-Simile },indrance from work—most Fac-Simile Gold Medal obstinate cases conquered. Grand Prix Soft as velvet—easy to apply— inexpensive. i" Gold Medal and Grand Prix. Process of recovery_i8 natural, so afterwards no further use for trusses. We prove it by sending Trial of Plapao absolutely FRE Write name on Coupon and send TODAY: Plapao Co., 790 Stuart Bldg., St. Louis Mo.

Oe Prey er ee SY a TS. Return mail will bring Free Trial Plapao.

Page 119

> w Pet Se of nd est m! INC, J.

inning oducer y free. aste a icago

March, 1923 AutoMenWangted —— jobs EPO he here in California ato oy are wanted, ea gape en can’t be trained fast Enough tp supply demand. California is crowded with autos. Has more autos to ge than any other state in Union. Greatest shortage ever known of gar- ages and skilled auto mechanics. Learn Auto Trades in Coast’s Biggest School Now’s YOUR opportunity to step into this big money- making business. YOU can become an electrician, me- chanio, ignition expert, garage foreman or used-car ap- praiser after.a few short weeks training. We'd like to tell you here hov: thousands of: men have gained big-pay auto jobs througtr NA*EIONAL training. But it’s a long story, en ve.put'itall.in a.handsome illustrated book which also tells everything about NATIONAL AUTOMO.. T Wonderful big training shops right next door to 130-acre city park. Ball parks, swimming pool, world’s largest stadium—all free to you. Send for this book now, Your Success Is Sure After ATIONAL Training H dreds of:men write: “I have increased my earnings Mo” Ihave built a wonderful garage business, and jon it all to National.” “Iam well satisfied with National training; am sendihg my brother to take the course.” It's the National practical shop training that counts, Adtual construct- ion work on all types of motors. Ignition, battery and lathe work— driving and vulcanizing. Special advanced electrical course FREE. You KNOW autos when you complete the NATIONAL course. Special Low Tuition offer now. Earn your room and board, and a little more, while learning. Living expenses low in California—and it's worth a million dollars to live there. Find out about everything in in- teresting illustrated auto book. Send for this big FREE book. Mail che coupon NOW, Sa te ee eee ee ee ee q Send for Big Free Auto Book, NATIONAL AUTOMOTIVE SCHOOL Dept. 24, 811 S. Figueroa St., Los Angeles, Cal. Please send me your 72-page illustrated Auto Book —absolutely FREE, postage prepaid. ee We Wh he me a ene UNINC gv i oar ra, aii erbre ss elorare.eiare.svels 68.8 4186

Reg bcctey ora ciieauswisss <8 car erele RO gs cscien ais see { : ia No) Old Sown Cances

ALONE— with the Only Girl An “Old Town Canoe’ means happiness for you and the only girl. Means afternoons together, drift- ing down winding streams—lazy- paddling on quiet waters. Canoeing is one of the greatest of summer pleasures—and the cheap- est. Foran “Old Town Canoe” will last you for years. And it is the low- est-priced canoe made. $54 up from dealer or factory. It is the lightest and steadiest of canees, too! The new 1923 catalog shows all models in full colors. Write for one today. It is free. OLD TOWN CANOE CO. | 1393 Main Street, Old Town, Maine, U.S.A

THE HOME WORKSHOP The Shipshape Home (Continued from page 132)

will be toward the ceiling. Lift the stand on the scaffold and place it about 4 ft. from the end where you intend to begin paper- ing. Take the end of the paper in both hands and attach about 1 ft. of it to the ceiling by pressing it with both hands and smoothing it with the brush or whisk. Take every care to start with the long edge of the paper exactly even with the edge of the ceiling and wall. If you do not start right, you will have to take the paper off and begin over again, but that is not difficult to do if you have not taken more paper off the little helper than you can handle. If there are any wrinkles that cannot be brushed out, loosen the paper back to the wrinkles and brush it on again. Work quickly but do not hurry too much, as the paste will remain damp for some time. Hold the paper against the ceiling with one hand and move the helper about 2 ft. with the other, letting the paper slip off the pile. Brush the center of the paper until-the slack is taken up and then brush out- wardly toward each edge. Repeat this process until you are about 4 ft. from the wall. Then, using a roll made of odds and ends of cut pieces, take the remaining paper from the helper and support it with the roll. You can then brush down the center clean to one end, and return and brush out each edge. Look back to see if there are any wrinkles or bubbles. If so, smooth them with the roller. Paste another length and repeat the pro- cedure. See that the edges overlap so that one edge just covers the other. The ten- dency is to have too large an overlap. When the second sheet has been applied, roll the seam.—A. M. SMYTH, German- town, Pa.

“tem For work that is Painting |-smooth and in good ints condition, 1 gal. of Hin paint of standard qual-

ity will cover from 600 to 800 sq. ft. with one coat or half that with two coats. Fill all nail holes, cracks, and crevices with pure linseed oil putty, after the first priming coat is dry. For house painting, use a long flat or oval bristle wall brush, and see that the paint is well worked into the wood. In applying the priming coat, do not try to cover the grain of the wood simply by piling on the paint thickly. Several thin coats are better than one heavy one. For three-ceat work, the second coat should have sufficient turpentine added to reduce the surface gloss. The third coat will then stick better than it would to a glossy second coat. If the paint for the finishing coat seems somewhat heavy, add a little raw linseed oil. Always allow at least 48 hours between coats.

IN SELECTING tints for house painting, it is best not to duplicate the colors of neighbor- ing houses, but to choose colors that will harmonize. If you | wish your house to stand out, ~use the | lighter tints. Brilliant eolors are best for | gmall houses. Choosing Colors

133 EARN #4 0D::: _ Living Expenses Paid

Big Opportunities for YOU in Hotel Work More Positions Open Than We Gan Fill £0,000 men and women wanted by leading hotels. Opportunities unlimited—need not half supplied. New Hotels now building asking us for graduates.

A big prof nas new, uncrowded. “pa penta WANTED quarters, rapid | Standard Business advancement. A it. 44 | Training Institute chance to live in graduates are luxury, among lwanted for Fol- while, lowing Positions open (partial list) : How to |2asv't. Managers Salary $300-$400 Mo. Prepare Apartment and Meals Yourself | , poom clerks You can qualify | Salary $225-$250 Mo. for a good-paying Meals position by devot- 2 Mail Clerks ing spare time at Salary $150 Mo, home to a series Meals of easily under- 1 Steward stood, inexpensive lessons, known asthe | Salary $375-$435 Mo. Hotel Operation and Meals Management Course covering every phase of the hotel business. Compiled by nation- ally known hotel ex- 1 Housekeeper Salary $175 Mo. Apartment and Meals perts; our oe 12 Floor Clerks training endorse y leading hotel execu- Salary ta Mo. tives such as Roy Carruthers, Manag- ing Director, « The Waldorf-Astoria, New York; Senator Van Orman of the Van Orman hotels in the Middle West, and others. A POSITION IS WAITING FOR YOU More applications received daily for our graduates than we can supply. One new 50-room hotel has placed order with us to fill every position with our graduates. Posi- tions ready to be filled in all parts of America, large and small hotels, Will you qual- ify? Mail this coupon today for booklet and latest Employ- ment Bulletin listing many positions open. 6 Food Checkers Salary $90 Mo. Room and Meals More positions open than we can fill

Standard Business Training Inst., 1188 Cariton Court Buffalo, N. Y. STANDARD BUSINESS TRAINING INST. 1188 Car!ton Court, Buffalo, N. Y. Sénd me free booklet No. 1188 giving full information about Hotel Operation and Management Course; also Employment Bulletin.

Page 120

Popular Science Monthly 7 ’

THE HOME WORKSHOP Table Makes Inexpensive Desk for Small Shop . AN OAK rolltop desk would be out of place in the small workshop and would _ soon get scratched and scarred, but a desk | almost as serviceable for keeping corre- | spondence, reference books, plans, and mis- _ cellaneous data, can readily be made from | a kitchen table. Such a table in unpainted | pine or oak can be obtained for a few dollars, Fix a sheet of zinc to the top of the table, fasten two uprights at the ends, as shown,

ssa test

ger +-\EDGE AROUND SHEL

WRI ara Rent whe 5 re Rsan Four Tubes Now Do the Work of Seven Again Erla offers invaluable contribution to radio science. The Quad-Six Super-Radio-Frequency Circuit—an Erla achievement — takes first place among the notable discov- eries of the year. Six stages of amplification—four radio and two audio— are secured with the use of but three amplifying tubes, and a ZINC NAILED + | detector, giving the efficiency of the best seven-stage SUBSTANTIAL’ ~,TO TOP circuits of conventional design. | KITCHEN = Ge a Ask your dealer for our Special Bulletin No. 14, giving full woe information about this latest and most efficient of circuits, ‘ : Erla radio frequency trans- | with complete directions for installing. Or write us, giving ode Bl ._o— aaiiare, shh meiiies formers are used exclusively our dealer’s name. 2 in the new Quad-Six circuit, y home workshop being responsible for tts effi- ° ° cigomiinceneine tes er fg. fA Electrical Research Laboratories and make a boxlike shelf arrangement with : 7 ay aie . hinged doors. The zinc will stand unlimited abuse and can easily be kept clean by rub- bing it with a piece of waste. The long drawer under the table top holds rolled ys

We Pa $7 a Day prints, while the smaller compartments Every Week y. onderfolinvention. The SERE- above provide a place for drawing instru- , LA does more than machines ent i That's what R. oe g -¥ bt a ments, books, papers, miscellaneous data amazing New Kind of Heat that taken b 1 and other items that cannot safely be Ng: FE —_ i laced in a bench d —H.L.F eliminates, worry about na day. smand. placed in a bench drawer. A ng, fortunes, too 1 Burner. 3 a

Low price. guaranteed. Easy to Take Orders Tractor Pulley Drives Tool eee ged roe eneey dav. Grinder Clamped to Wheel given. Write for terms. PERRY-LUDLOW CO., S.647 DAYTON, O. N SHARPENING those farm tools that ordinarily are sharpened on an emery or carborundum hand power grinder, much _ time can often be saved by driving the | grinder from the tractor pulley, as illus- | trated. | The handle of the grinder is removed _ and a 5- or 6-in. pulley substituted. The

ZEST Rin phan ippneeie ston tl ea! yd DRIVE PULLEY Italian Period in 2 = ) Buffet 4 P-110 Volt $13 50 ||| Yours for 20c a Day

ities A complete Dining Suite if you wish or single pieces ye f.e.b. in this same design, the imposing Italian Renais- esl « \ PULLEY SUB- A C Ma t . sance. This Buffet, China Cabinet, Chairs, Table, J iN R —— 0 or a all in genuine American Walnut, the popular two- Z \" oe ” (WORTH ABOUT DOUBLE) pee ca, yo Designs low _—— ye terms, in our big Larkin Book of Better Homes, showing over | | A labor saving arrangement for the Has many fine exclusive 1000 attractive offers of Furnishings for the home. farmer in sharpening tools and blades feat Check below for offer interested in. preparatory to spring work eatures 1 To 4 Years To Pay Fo ; Grin der an d B uffer $ 95 .00 [1] Peldhiegs ( Symphonic Player Pianes | grinder is then clamped to the rim of the Eo. b. Chicage

7 (esateatS melee ee , + Ds tractor wheel or to any support that wiil —6 and 7 inch wheels, [_] Symphonic Piano Symphonola Phonographs ‘eon a : tor fan-cooled and dust proof. wero ~ ath Lt Som d Today) , bring its pulley in line with the broad face ae ee ee ET ee ee, ee pea once our ener eerens wi + Slee meted prices of the tractor drive pulley, and a short > . y: gu on these attractive Furnishings an usical Instruments. length of belting is used to connect the two. antee protects you. Write for Bulletins de- e scribing these and other sizes. Get Our Low Prices If several cutting wheels are provided Hurry this ad—check 4 ee full name and address for the grinder, practically every form of NORTHWESTERN ELECTRIC CO. TODAY for big FREE " A knife tool, from a mower blade to a circular 410-420 S. Hoyne Ave., Chicago, III. _ eps tht co ee a nett, dann bentimamemall ies Wile cones <tc