James Prescott Joule, of Salford, England, developed revolutionary ideas on energy and temperature. In 1843, he proposed the Mechanical Equivalent of Heat, which included a constant describing the conversion of a given amount of work into heat. The international unit of energy, the joule, is named in his honour.

This site includes a virtual recreation of his famous paddlewheel experiment, access to Joule’s original apparatus in the collections of the Museum of Science & Industry in Manchester, further information about Joule and his work and National Curriculum resources.