#2. Perpetuum Mobile of Villard de Honnecourt (about 1230)
A drawing of a perpetual motion machine appeared in the sketchbook of Villard de Honnecourt, a 13th-century French master mason and architect. The sketchbook was concerned with mechanics and architecture. Following the example of Villard, Peter of Maricourt designed a magnetic globe which, if it were mounted without friction parallel to the celestial axis, would rotate once a day. It was intended to serve as an automatic armillary sphere.