William Murdoch (1754–1839)

The mechanical engineer William Murdoch (or Murdock) was one of the most brilliant and prolific inventors of the British Industrial Revolution. Among his many innovations were improvements to Boulton and Watt steam engines and the introduction of coal-gas production and lighting.

His father was a millwright and tenant of a corn mill in south-west Scotland. He attended local schools and learned about mechanics by working with his father. At the age of 23, his ambition was to join Boulton and Watt, the outstanding mechanical engineering company in the world. He walked 500 km from his home to Birmingham, where James Watt gave him work in 1777. He became a trusted employee. For nearly twenty years from 1779 he represented Boulton and Watt in Cornwall, where they provided numerous steam engines for tin and copper mines. He erected engines, maintained them and improved their performance. He helped frequently with projects elsewhere and in 1798 he was called back to Birmingham to run the foundry. He joined the scientific circle known as the Lunar Society of Birmingham, which included Boulton and Watt, Josiah Wedgwood, Joseph Priestley, Benjamin Franklin and John Smeaton. He was a partner with Boulton and Watt from 1810 until he retired aged 76.

Murdoch has been called the ‘third man’ of Boulton and Watt. He was responsible for numerous developments for the steam engine, though James Watt and his son partly concealed his importance. In 1781 the company saw opportunities to sell engines to mills and factories if they could produce reliable rotative motion from their reciprocating beam engines – a key development of the Industrial Revolution - Murdoch devised the Sun and Planet Gear, patented in Watt’s name. In 1782 he invented an iron cement to seal steam engine components. In 1799 he patented the long ‘D-slide’ steam valve. For marine markets, Murdoch designed the engine for Robert Fulton to use in the world’s first steamboat, at New York in 1807 and headed the production of marine engines for the company.

While in Cornwall in the 1790s Murdoch experimented with coal gas and demonstrated its properties for the first time. He lit his house in Redruth with gas in 1792 and in 1795 he demonstrated methods for producing and storing gas and gas lighting at Neath Abbey Ironworks in south Wales. In 1802 he installed lighting in the Boulton and Watt works and in 1805 the company began supplying lighting to textile factories. He published a paper on the subject in 1808 and was awarded a gold medal by the Royal Society. Gas lighting was later used internationally.

Murdoch’s inventive mind produced many other ideas, including new methods for boring wooden pipes, stone pipes and iron cylinders, a steam cannon and steam gun, machine tools for the Boulton and Watt factory, a precipitate for clarifying beer in brewing and the first gravity-fed hot-water system. He built working models of steam carriages from 1784 to 1795 that may have influenced Richard Trevithick to devise the first railway locomotive in 1802. He developed the use of compressed air and built the first pneumatic tube to carry messages.