horse mill

A horse-mill is a mill that uses a horse as the power source. Any milling process can be powered in this way, but the most frequent use of animal power in horse-mills was for grinding grain and pumping water. Other animals used for powering mills include dogs, donkeys and oxen. These are all forms of animal engines. Man, can also be considered to be an animal, and engines powered by man include treadwheels.
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