Capstan

A capstan is a vertical-axled rotating machine developed for sailing ships to multiply the pulling force sailors could exert when hauling ropes, cables and hawsers, working on the same principle as a windlass except that a windlass turns on a horizontal rather than a vertical axle. Sailors wrapped rope around the rotating drum and inserted bars as levers to walk it round, gaining the mechanical advantage needed to weigh anchor, hoist sail, shift spars on a mast or move cargo. Both the device and its name are considered Spanish inventions, the word tracing through Old Provencal and Old French back to the Latin capistrum, a halter, and entering English in the fourteenth century probably by way of Portuguese or Spanish seafarers. Early capstans were simple rotating timber posts, later built as wooden drums on iron axles, and by the nineteenth century steam-powered and hydraulically powered versions appeared; a modern capstan is driven electrically, hydraulically, pneumatically or by internal combustion engine, usually through a gearbox that trades rotational speed for torque.