Capstan

Modern tourists turn a capstan. Sailors would coordinate the rhythm of their movements by singing a particular type of sea shanty as they walked around the capstan. The tensioned portion of the rope would hoist a foresail and could also be used to lift a heavy spar into position on the mast or to transfer cargo to or from a dock or lighter.

A capstan is a vertical-axled rotating machine developed for use on sailing ships to multiply the pulling force of seamen when hauling ropes, cables, and hawsers. The principle is similar to that of the windlass, which has a horizontal axle.

A capstan on a sailing ship. The upper portion is operating the anchor windlass below in the Forecastle

Below the capstan shown above is the anchor windlass

In its earliest form, the capstan consisted of a timber mounted vertically through a vessel’s structure which was free to rotate. Levers, known as bars, were inserted through holes at the top of the timber and used to turn the capstan. A rope wrapped several turns around the drum was thus hauled upon. A rudimentary ratchet was provided to hold the tension. The ropes were always wound in a clockwise direction.

Capstans evolved to consist of a wooden drum or barrel mounted on an iron axle. Two barrels on a common axle were used frequently to allow men on two decks to apply force to the bars. Later capstans were made entirely of iron, with gearing in the head providing a mechanical advantage when the bars were pushed counterclockwise. One form of capstan was connected by a shaft and gears to an anchor windlass on the deck below. On riverine vessels, the capstan was sometimes cranked by steam power.

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