History
Further information: WatermillIn water-raising devices rotary motion is typically more efficient than machines based on oscillating motion. In terms of power source, water wheels can be turned either by human or animal force or by the water current itself. Water wheels come in two basic designs, either equipped with a vertical or a horizontal axle. The latter type can be subdivided, depending on where the water hits the wheel paddles, into overshot, breastshot and undershot wheels. The two main functions of water wheels were historically water-lifting for irrigation purposes and milling, particularly of grain.
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Famous quotes containing the word history:
“The principal office of history I take to be this: to prevent virtuous actions from being forgotten, and that evil words and deeds should fear an infamous reputation with posterity.”
—Tacitus (c. 55c. 120)
“This above all makes history useful and desirable: it unfolds before our eyes a glorious record of exemplary actions.”
—Titus Livius (Livy)
“America is, therefore the land of the future, where, in the ages that lie before us, the burden of the Worlds history shall reveal itself. It is a land of desire for all those who are weary of the historical lumber-room of Old Europe.”
—Georg Wilhelm Friedrich Hegel (17701831)