David Joy 1825 - 1903

David Joy (1825–1903) was a British mechanical engineer and inventor, associated with the design of the “Jenny Lind” locomotive (1847) and renowned for developing the radial valve gear (1879). Born in Leeds, he trained as a draughtsman and began his engineering career at Fenton, Murray and Jackson before joining the Railway Foundry, where he became chief draughtsman and contributed closely to the Jenny Lind design.

Joy held superintendent posts with the Nottingham and Grantham Railway (1850) and the Oxford, Worcester and Wolverhampton Railway (1853–1856), returning later to the Railway Foundry. He also worked extensively in marine engineering during the 1850s, developing a compound engine, steam reversing gear, and hydraulic organ‑blowers used in major public buildings.

During the 1860s he pursued a wide range of engineering inventions, including steam hammers and early processes for utilising slag. In 1874 he joined the Barrow Shipbuilding Company, where he completed the design of his radial valve gear, later widely adopted by several British railway companies and by marine engineers. In the later part of his career he developed further inventions in partnership with his sons and presented papers to several engineering societies.

Joy died at his home in Hampstead, London, in 1903.