Windlass

Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt.

[1] A surviving medieval windlass, dated to 1360 –1400, is in the Church of St Mary and All Saints, Chesterfield.

[2] 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 (fl. 1290–1333).

Since each turn of the crank raises the pulley and attached weight by only π(r − r′), very large mechanical advantages can be obtained.

The captor then twisted a stick in the rope until it tightened and caused the man's wrists to swell.

Turnbridge windlass lifting road bridge over Huddersfield Broad Canal
Differential windlass
Comparison of a differential pulley, or chain hoist, at left, and a differential windlass, or Chinese windlass, at right. The rope of the windlass is depicted as spirals for clarity, but it is typically helices with axes perpendicular to the image.
Two Spanish windlasses on a bunch of sticks, in the starting position and tightened