1-152-659 - Ann Ronan Picture Library/Heritage-Images

Model of a Newcomen steam engine, 1856. It was while repairing this engine that James Watt (1736-1819) is said to have invented the separate condenser, which greatly improved the efficiency of steam engines. Thomas Newcomen (1663-1729) designed his atmospheric or 'steam' engine in 1712. Water was heated in the boiler and the resulting steam was let into the cylinder, pushing up the piston. The steam was then condensed, bringing down the piston. The piston rocked the beam which worked the pump. It was safer and more effective than the earlier Savery engine and was widely used to drain water out of mines. From Memorials of James Watt by George Williamson, 1856.