born Aug. 19, 1808, Edinburgh, Scot.
died May 7, 1890, London, Eng.
Scottish engineer.
Son of the artist Alexander Nasmyth (1758–1840), he is known mainly for his invention of the steam hammer (1839), an important metallurgical tool of the Industrial Revolution . He also devised tools such as a planing machine, a steam pile driver, and a hydraulic punching machine, and he manufactured more than 100 steam locomotives. He retired at 48 to devote himself to his hobby, astronomy.