A piece of mechanism, working on the principle of the wheel and axle, on a vertical axis, the power being applied by movable bars or levers…

In the navigation of the river Thames, a revolving apparatus at the river-side, round which a rope was wound to haul craft through difficult…

U.S. A steam-driven capstan used on some riverboats; a steam engine used to drive such a capstan (also more fully nigger engine). Now rare.