Think Tank

Smethwick Engine

Smethwick Engine in action

The Smethwick Engine is the world's oldest working steam engine. It was based on James Watt’s patent design of 1769 and built in 1778. James Watt (1736-1819) was a Scottish inventor and mechanical engineer, whose partnership with Matthew Boulton created an engineering firm of international importance. 

Other than its impressive age, the Smethwick Engine is significant for having ‘a new method of lessening the consumption of steam and fuel in fire engines’. It was the first engine in the world to use both the expansive force of steam and a vacuum at the same time. The vacuum is created inside a separate condenser, low pressure steam is then applied onto the top of the piston and the vacuum is applied onto the underside. This engine design was more powerful and required less coal to run than others of its time. 
The engine was used to pump water to the top of a series of canal locks in an area near Birmingham called Smethwick. The remains of the building the engine was housed in are preserved on its original site near the canal. Prior to the installation of the engine, only 50 boats a week could pass through the locks. This number increased to 250 when the Smethwick Engine was in place. 

The video below shows the Smethwick Engine in action when run on live steam at Thinktank

Birmingham Stories

Log on to the Thinktank on-line exhibition comprising four zones crammed with remarkable stories and multimedia clips featuring historic objects from the Science and Industry collection.