(born Feb. 28, 1663, Dartmouth, Devon, Eng.—died Aug. 5, 1729, London) British engineer. In 1712 he built his atmospheric steam engine, a precursor of James Watt's engine. In the Newcomen engine, atmospheric pressure pushed the piston down after the condensation of steam had created a vacuum in the cylinder. Newcomen engines were used for some years in the draining of mines and in raising water to power waterwheels.

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