Abstract: Atmospheric pollution and global warming have been caused due to conversion of petroleum, natural gas and atomic energy into electrical energy and continued use of the first two of these energy sources as engine fuel. Such being the case, there is a pressing need to use alternative energy and to change from using power mechanisms to using alternative types of mechanisms. Disclosed is a human-powered device provided with a first lever and a second lever. A large force is generated using a first lever. By means of a second lever, the force is further amplified, and swing amplitude is enlarged. The fulcrum position is made to move, with the result that the second lever is provided with a continuously variable function. A pinion makes normal or reverse rotation according to the movement of the second lever, which swings. By means of a ratchet mechanism provided at a first shaft, this normal or reverse rotation is converted into rotation made in one direction only by a gear wheel.