Steam donkey

Steam donkey, Steam-powered winch or logging engine.

Steam donkey image

Steam-powered winch or logging engine 12×14 Empire steam donkey in the UBC Malcolm Knapp Research Forest, Maple Ridge, British Columbia, Canada

A steam donkey or donkey engine was a steam-powered winch once widely used in logging, mining, maritime, and other industrial applications.

Steam powered donkeys were commonly found on large metal-hulled multi-masted cargo vessels in the later decades of the Age of Sail on through the Age of Steam, particularly heavily-sailed skeleton-crewed windjammers.

A donkey used in forestry, also known as a logging engine, was often attached to a yarder for hauling logs from where trees were felled to a central processing area. The operator of a donkey was known as a donkeyman.

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Name

Steam donkeys acquired their name from their origin in sailing ships, where the "donkey" engine was typically a small secondary engine used to load and unload cargo and raise the larger sails with small crews, or to power pumps. They were classified by their cylinder type – simplex (single-acting cylinder) or duplex (a compound engine); by their connection to the winches (or "drums") – triple-drum, double-drum, etc.; and by their different uses.

A good deal of the cable-logging terminology derived from 19th-century merchant sailing, as much of the early technology originated in that industry. Common logging terms include high-lead yarder, ground-lead yarder, loader, snubber, and incline hoist.

History

In logging

Steam donkey on display at Disney California Adventure Park theme park

John Dolbeer, a founding partner of the Dolbeer and Carson Lumber Company in Eureka, California, invented the logging engine in that city in August 1881. The patent (number: 256553) was issued April 18, 1882. On Dolbeer's first model, a 150-foot, 4+1⁄2-inch manila rope was wrapped several times around a gypsy head (vertically mounted spool) and attached at the other end to a log....read more

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