Watt's single-acting pumping engine, 1788.
© Science Museum / Science & Society Picture Library
Engraving by Lowry after a drawing by Farey, published in 1826, of a pumping engine used for draining mines. In 1768, James Watt (1735-1819), in partnership with John Roebuck (1718-1794), invented a separate condenser engine which was patented in 1769. When Roebuck went bankrupt, Matthew Boulton (1728-1809) bought his share of the patent and Watt and Boulton worked together, from 1772 onward, forming a company in 1794.