windlass

thumb|Turnbridge windlass lifting road bridge over [[Huddersfield Broad Canal]] thumb|200px|Differential windlass

The windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. A winch is affixed to one or both ends, and a cable or rope is wound around the winch, pulling a weight attached to the opposite end. The Greek scientist Archimedes was the inventor of the windlass. A surviving medieval windlass, dated to –1400, is in the Church of St Mary and All Saints, Chesterfield. The oldest depiction of a windlass for raising water can be found in the Book of Agriculture published in 1313 by the Chinese official Wang Zhen of the Yuan Dynasty ( 1290–1333).