JF Ptak Science Books Post 797 (Sept 2009) Extended.
In 1702, at the beginnings of the Industrial Revolution, Thomas Savery (c.1650 - 1715) began the idea of calculating the work done by steam engines over that done by horses, writing in his book, The Miner's Friend:
"So that an engine which will raise as much water as two horses, working together at one time in such a work, can do, and for which there must be constantly kept ten or twelve horses for doing the same. Then I say, such an engine may be made large enough to do the work required in employing eight, ten, fifteen, or twenty horses to be constantly maintained and kept for doing such a work…" But it was James Watt who first introduced the term ”horsepower” while trying to advertise and place forever the idea of his steam engine over than of the earlier Newcombe engine and, of course, horses.”
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