The Newcomen Pumping Engine

As much as anyone, Newcomen was responsible for initiating the Industrial Revolution. His mechanical pumping steam engines were in use from 1712 until at least 1901. In 1800 some 2,000 of his engines were estimated to be in use throughout Europe.

Coal and tin mining had long been important industries, but as shallow mines became exhausted deeper shafts were needed. Flooding was a constant problem and water needed to be continually pumped out. Water pumps had been known since antiquity, they had proved hard to scale up to the needs of deep mines.

Newcomen’s innovation was pump steam into a vertical cylinder closed at the bottom and with a piston at the top, linked to the pump by a pivoting beam. The weight of the pump would naturally tilt the beam and raise the piston to the top of the cylinder. Steam was injected into the cylinder and then suddenly condensed by a spray of cold water, creating a vacuum. Atmospheric pressure would then drive the piston down into the cylinder activating the pump; the vacuum was then released with a further injection of steam and the piston would then lift up to the top again, resetting the pump.

This worked reliably at around 5 strokes per minute but was extremely inefficient, owing both to leakages due to the rudimentary manufacturing technology of the time, and to the huge amount of coal needed to generate the steam. At coal mines with plentiful cheap coal on hand, this mattered less than its functionality.

The engine illustrated drained a coal seam at Caprington Colliery in Argyll, Scotland at a depth of 50 metres and worked continuously for 90 years. It is now displayed at the National Museum of Scotland in Edinburgh.

It was not until 1776, some 60 years later, that James Watt developed a much more efficient engine based on Newcomen’s design principles and took the steam engine out of the mines and into wider manufacturing.