A perpetuum mobile (Latin for "perpetual motion machine") is an apparatus capable of doing work without supply of energy. It has been the dream of inventors since ancient times and continues to pop up in sketches and drawings of would-be inventors every now and then but in 1775 the Royal Academy of Sciences in Paris issued the statement that the Academy "will no longer accept or deal with proposals concerning perpetual motion". (Why?) Please look for information about perpetual motion machines, select one and post a message describing it. Did it work?