Scottish engineer and inventor of the steam hammer.

As a teenager James and his brother, George, built model steam engines and a real steam carriage. In 1829 James became personal assistant to Henry Maudslay, absorbing the ways of his master. In 1834 James and George set up their own engineering works in Manchester, specialising in making and improving machine tools, a field they soon dominated.

James is usually credited with the invention of the steam hammer in 1839, which he patented in 1842. This machine greatly assisted his expansion into steam locomotive manufacture. The brothers were so successful commercially that James could afford to retire in 1856, aged just 48. On his death in 1890 his estate realised the enormous sum of £243,805.