It was preserved as a memorial to Thomas Newcomen (d. 1729), inventor of the beam engine, who was born in Dartmouth.

[2] Newcomen engines were used for applications that required the raising of water, such as the draining of coal mines.

The surviving engines of this period have mostly been moved from their original leading-edge sites to some quiet backwater, often pumping water into canals, where they languished with only intermittent use.

This was often seasonal, pumping only being required during a dry summer, and so the heavy coal consumption of an early engine was acceptable.

[ii] The early history of this engine is unclear but it was built some time around the start of the 18th century.

Newcomen constructed an engine for Griff Colliery[5] near Nuneaton in 1714 "to draw water by the impellant force of fire".

[6] The first engine was to be capable of pumping 16,700 litres of water per hour from the mine, with a maximum depth of 140 feet (43 m).

It is likely that this was a rebuilt version of the first engine, with the original brass cylinder replaced with a larger 22 inches (560 mm) bore one of cast iron with a stroke of 5 feet (1.5 m).

[3] The engine was not large, even for its time, and used a simple 12 feet (3.7 m) one-piece wooden beam, without additional struts or being made of multiple laminated timbers.

The Engine also shows evidence of a patched hole in the side of the cylinder, where the original Newcomen injection valve was removed.

By claiming that the pickle pot was an 'extension' of the main cylinder, rather than a separate component, it avoided infringing the Watt patent.

A requirement for this was also that the haystack boiler was moved away from its traditional Newcomen position, directly beneath the cylinder.