Cornish Pumping Engine built by Harvey & Co of Hayle, Cornwall, for display at the International Exhibition of 1862

This superbly constructed engine - it might be termed a model, but it is in reality simply a small version of what was ordinarily a much larger machine - was built by one of the foremost British engine-builders, Harvey & Co of Hayle. Harvey's acquired a formidable reputation providing engines to pump water in Cornish mines, for water supply, and drainage purposes, around the world, which made the company well known and attractive to many engineers eager to make their name.

The engine uses steam in a cylinder at one end of the beam to lift a heavy counter-weight, which on its descent drove a force pump - in real-world applications, this pump might lift floodwater from mines, or drinking water to a reservoir. In this case, the oil used in the system instead of water is recirculated, allowing the engine to operate in a self-ciontained way in exhibitions - as it was indeed used at the 1862 International Exhibition in London, where it would have been an impressive and fitting example of this company's justly famous products.