A mechanical contrivance working on the principle of the wheel and axle, on a horizontal axis (thus distinguished from a capstan); consisting of a roller or beam, resting on supports, round which a rope or chain is wound; used for various purposes, esp. on board ship for weighing the anchor or hauling upon a purchase, at the head of a mine-shaft for hoisting coal or other mineral, or for raising a bucket from a well [OED]

Note 592.2