Fragment of Watt's rotary engine, 1782

As well as his large beam engines, James Watt attempted to make an engine without a piston and cylinder, using pure rotary motion. In this, a steam jet spun the three blades around a shaft. It was premature – an effective rotary steam engine did not arrive until 1884 with the Parsons turbine. But it demonstrates Watt's ability to think far ahead.