Original model of William Murdock's Oscillating Cylinder Engine, 1785
This is thought to be an original William Murdoch experimental model of 1785. The model’s cylinder is made of wood, with a simple slide valve and eccentric-driven air pump. It is a very early essay in a small and self-contained engine, which Murdock later returned to with the side-lever or bellcrank engine. Murdock's employers, Boulton and Watt, did not pursue the oscillating engine as a design as they did the bellcrank engine, but it was adopted on a considerable scale for early marine engines during the nineteenth century under the auspices of Joseph Maudslay.