Part of voltaic cell
Part of voltaic cell used by James Joule, c.1840.
This electric cell was used by the scientist James Joule for experiments about energy. Joule was a Salford resident and the son of a brewer. He was taught by the famous scientist John Dalton. Joule's experiments in 1845 led him to an new understanding of energy conversion.
Research by Joule showed that electricity, mechanical work and heat are all the same thing - forms of energy. He used equipment like this to learn that forms of energy are interchangeable and that energy cannot be created or destroyed. Joule is remembered as one of the founders of modern physics. From 1948 the Joule became a standard international unit of energy measurement.
Electric cells joined together become a battery. When Joule used this cell, electricity was at an early experiemental stage and was not yet a commercial technology.