Show A perpetual motion clock since 1914 a clock la in dayton ohio has been running without being wound it Is equipped with a thermal motor consisting of it a gallon tank filled with alcohol a ono one half balf inch cylinder and piston with a ten inch stroke A rise in the temperature expands the alcohol pushing the piston up with a serles series of weights weighing sixty pounds A fall in ili temperature allows the weights to descend wind tug lug the springs in the clock movement popular mechanics magazine |