Close up we see pistons move up and down or side to side. Pendulums sway, the small parts of machinery move. Gears drive larger wheels. Gears within gears spin. Shafts turn some mechanism that is out of sight. Screws revolve and move other gears; a bit rotates. More subtle mechanisms move other mechanical parts for unknown purposes. Weights rise and fall. The movements, underscored by sound, are rhythmic. Circles, squares, rods, and teeth are in constant and sometimes asymmetrical motion. These human-made mechanical bits seem benign and reassuring.
Released in 1930, Mechanical Principles is a documentary film (United States of America). It was directed by Ralph Steiner. With a runtime of 11m, the film averages 6.8/10 across 22 TMDB ratings.
To watch Mechanical Principles online free in HD, press Watch Now above and pick any server; the movie plays instantly on MyFlixer with no account needed. If you like documentary movies, Be Natural: The Untold Story of Alice Guy-Blaché, Spider-Man: All Roads Lead to No Way Home and Come See Me in the Good Light are worth adding to your list.