I had a buddy in high school that ran the movie projector at our local drive in movie theater. (Ca. 1974). He let me in the projection shack to watch him work once. He had a large motor that drove a DC generator. He first cleaned up the commutator with some sandpaper wrapped around a wood stick. Then he mounted a carbon rod in the projector, started the screw drive and turned on the power. That was cool stuff. The carbon rod, I think could last one reel which was about an hour. He had two projectors and both were required to show one complete movie.
2nd story: In Ag class in high school we were rebuilding the engine on an old Oliver tractor. It used a magneto ignition and had a crank on the front as backup for starting the engine. The engine was torn down but the block and crank were still mounted in the tractor with the magneto. So as a right of passage, each one of us had to hold on to a spark plug wire while someone spun the crank. And the faster you can crank the stronger the magneto pulse. We had one large kid who could hold onto the spark plug wire no matter how fast someone would spin the crank. He just stood there saying, “he he he.” Scary guy.