This video lists a number of perpetual motion machines that have been proposed throughout history:
- Robert Boyle's Self-Flowing Flask
- A "perpetual train" using rolling cones
- F. G. Woodward's hoop wheel machine
- Jacob Leupold’s Overbalanced Wheel
- Bob Schadewald’s Wheel
- Villard's wheel
These are all mechanical machines, which use gravity to operate, i.e, they are a way to transform the force of gravity into energy, and do not need batteries or motors. Since I think that those machines are not really perpetual motion ones, can they turn for hundreds of years or will it stop just after some minutes?