Newcomen atmospheric engine

The atmospheric engine invented by Thomas Newcomen in 1712, often referred to simply as a Newcomen engine. The engine operated by condensing steam drawn into the cylinder, thereby creating a partial vacuum, thereby allowing the atmospheric pressure to push the piston into the cylinder. It was the first practical device to harness steam to produce mechanical work. Newcomen engines were used throughout Britain and Europe, principally to pump water out of mines. Hundreds were constructed through the 18th century.

James Watt's later engine design was an improved version of the Newcomen engine that roughly doubled fuel efficiency. Many atmospheric engines were converted to the Watt design, for a price based on a fraction of the savings in fuel. As a result, Watt is today better known than Newcomen in relation to the origin of the steam engine.

Precursors

Prior to Newcomen a number of small steam devices of various sorts had been made, but most were essentially novelties. Around 1600 a number of experimenters used steam to power small fountains working like a coffee percolator. First an airtight container was filled with water, then heated to make it boil; a pipe extending to the bottom of the container and protruded upward from the container. The steam generated pressurized the container, displacing the water within out of the container, so that it spurted out of a nozzle on top of the container. These devices would have been limited in their effectiveness and could only serve to demonstrate a principle.