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. A windlass would be constructed above a shaft which allowed heavy buckets to be hauled up to the surface. 2  This process would be used until the shaft got below 40 metres deep when the windlass would be replaced by a 'whip' or a 'whim' .