How it began
Around 1710 Thomas Newcomen, an English ironmonger, developed an atmospheric reciprocating engine. In 1712 he and his partner John Calley produced the first working example to pump water at the Conygree Coalworks near Dudley, in the English Midlands. This Dudley Castle engine is generally accepted as the first successful Newcomen engine, although it may have been preceded by one he built near Wolverhampton.
Before it existed
Earlier steam devices had been tried but lacked practical use. Thomas Savery had developed a steam pump called the Miner's Friend in 1698, which did not use a piston. Savery held a general patent covering uses of steam power, so Newcomen and Calley persuaded him to join forces with them until that patent expired in 1733. Mines otherwise relied on pumps driven by horses.
How it works
A boiler supplied steam at very low pressure to a cylinder. Water injected into the cylinder cooled and condensed the steam, creating a partial vacuum, and atmospheric pressure then pushed the piston down. The piston hung by chains from one end of a rocking beam, and the other end worked the mine pump. Because the engine did not depend on suction alone, water could be raised from far greater depths.
How it spread
By the time of Newcomen's death, he and others had installed more than a hundred engines in the West Country and the Midlands, in north Wales, near Newcastle and in Cumbria. Hundreds were built during the 18th century, and the engines were used across Britain and Europe, mainly to drain mines. Evidence of a Newcomen engine was also found at Midlothian, Virginia.
What lasted
James Watt's later engine was an improved version of Newcomen's design that roughly doubled fuel efficiency by adding a separate condenser, and many atmospheric engines were converted to the Watt design. As a result Watt became better known than Newcomen in accounts of the steam engine. One Newcomen-style engine ran commercially from 1795 until 1923, and a full-size working replica of the 1712 engine was completed at the Black Country Living Museum in Dudley in 1986.
