'The Great Steam Hammer, Royal Gun Factory, Woolwich', 1896.
© Science Museum / Science & Society Picture Library
The steam hammer was patented by the Scottish engineer and inventor James Nasmyth in 1842. It took the human effort out of the proces of forging wrought iron and steel to form engine and machine parts, as well as substantially reducing production costs. This example, which had a head weighing forty tons, was installed at Woolwich in 1874. The actual downstrike of the steam-powered hammer was said to be equivalent to 1000 tons, and when in use, it was said that the hammer's impact could be heard and felt at the Greenwich Observatory two miles away.