Robert William Thomson (born June 29, 1822, Stonehaven, Kincardineshire, Scotland—died March 8, 1873, Edinburgh) was a Scottish engineer and entrepreneur, known as the inventor of the pneumatic tire.
Thomson was the son of the owner of a woollen mill and was sent at age 14 to Charleston, South Carolina, U.S., to live with an uncle and learn the merchant’s trade. Two years later he returned to Scotland, where he worked on various inventions, apprenticed in engineering workshops in Aberdeen and Dundee, and learned civil engineering in Edinburgh and Glasgow. While working in Edinburgh, he invented a system for detonating demolition explosives by electricity. Thomson then went to London and joined the South Eastern Railway Company, where he worked under prominent engineers Sir William Cubitt and Robert Stephenson (the latter the son of pioneering railway engineer George Stephenson).
In 1845 Thomson acquired a patent for a pneumatic tire—actually a hollow leather tire enclosing a rubberized fabric tube filled with air. Although a set of Thomson’s “aerial wheels” ran for 1,200 miles (roughly 2,000 km) on an English brougham, rubber for the inner tubes was so expensive that the tires could not be made profitably, and, thus, for almost half a century, air-filled tires were forgotten. The growing popularity of the bicycle later in the century revived interest in tire design, and in 1888 John Boyd Dunlop, a Scottish veterinarian living in Belfast, obtained patents on a pneumatic tire for bicycles, tricycles, and other vehicles. Dunlop later lost his main patent after it was discovered that Thomson had already patented the principle of the pneumatic tire.
Thomson went on to invent a fountain pen (1849) before he went to work for an engineering firm in Java (1852–62), where he designed a mobile steam crane. Back in Scotland, he developed and put into production a steam road vehicle that ran on solid rubber tires. Thomson’s machines were used to haul heavy loads on level and inclined ground and to provide omnibus service between Edinburgh and the port town of Leith.