Main component of model of the first steam engine condenser

James Watt

Tinplated iron cylinder, main component part of the first model of a separate steam engine condenser by James Watt, 1765. Taken from the contents of the private workshop of James Watt from his house of Heathfield, Birmingham, where he lived from 1790 to his death in 1819.

This is one of the most important objects in the history of steam power. With it, James Watt set about investigating how a separate condenser could be made to work, solving the paradox that for maximum economy a steam enginer cylinder had to be kept hot constantly, but for maximum power it had to be cooled once in every working cycle. The separate condenser reduced the fuel consumption fo an engine by between two thirds and three quarters, and in so doing made steam useable not just on coal mines, but anywhere that fuel and water could be supplied to. Contingent upon this discovery were immense changes in urbanisation, industrialisation, the rise of concentrated factory systems, demographic change and population growth, which characterised Britain's emergence as the world's first industrial nation. The model remained unidentified until the 1960s and was hidden among items on the bench in Watt's workshop, before curator Rodney Law realised its true identity.


James Watt's Garret Workshop
Object Number:
iron and tin plated
model - representation
  • visual and verbal communication
Major J.M. Gibson-Watt