DONKEY: see Ass.
A steam-engine of small or moderate power which works a crane or hoist, chiefly on board ship, to handle cargo and luggage. The steam is supplied by a donkey boiler, instead of being taken from the main boilers. A donkey pump is of very compact design, and suitable for being bolted to a ship's side, a column or wall, or a boiler. It is used for feeding boilers, tanks, vats, etc., and works by the direct action of a steam driven piston on a plunger in the pump cylinder. A flywheel helps to maintain a steady action of the pump. The smallest pumps, of the type shown (see p. 53o), deliver about 9ogal. per hour, and the largest 4,000.