# PHYSICS OF LEVERAGE & HISTORY OF MECHANICAL DEVELOPMENT SHELL OIL FILM MD61394

This black and white documentary film, Lever-age, History of the Toothed Wheel, explains the principles of levers and gears. It was presented by Shell Oil Company, directed by Geoffrey Bell, and narrated by famous announcer Harlow Wilcox. The Shell logo used from 1948 to 1955 finishes the film. However, a description of the 1939 film by Bell called Transfer of Power and also sponsored by Shell Oil matches this film and so this may be a re-release. The film opens with a girl pumping water, a man rowing in a boat, and an ancient carved stone depicting a crowbar (0:43-1:07). An antique counterpoise lift, commonly called a well sweep, is used to move water (1:08-1:22). The basic physics behind a class 1, 2, and 3 lever is demonstrated in a vintage animation (1:23-2:28). A pulley and bucket water well is shown, and the basic lever used to turn it is animated, which progresses into a toothed wheel (2:29-3:08). An antique wooden toothed wheel gear is shown turning a water wheel, powered by a camel (3:09-3:42). Water flows around a Norwegian mill grinding grains, and the antique wooden watermill components are shown, including the levers, shafts, and gears (3:43-5:16). An educational animation demonstrates the basic physics of gear ratio and speed (5:17-6:07). Windy plains with antique windmills in the distance are showcased up close, including their blades, axles, wooden toothed wheel gears, spur gears, grinders, and grain lifts (6:15-8:58). Different uses of antique mills are…

- Kind: Film
- By: PeriscopeFilm
- Genres: Science, History, Industrial and advertising
- Archive: [Internet Archive](https://archive.org/details/md-61394-shell-lever-age-vwr)
- Licence or status: none stated by the archive
- Who can watch: Tweens profiles and older (the archive gives no rating; placed by Invisible Network from its collection and subjects)

[Watch now](https://invisiblenetwork.ai/watch/archive/ia/md-61394-shell-lever-age-vwr?play=1)