Born June 9,1781, in Wylam, Northumberland; died Aug. 12,1848, at Tapton House, near Chesterfield. British designer and inventor who laid the basis for steam locomotion.

The son of a miner, Stephenson went to work at the age of eight. He learned to read and write at the age of 18 and through his persistence in self-education learned to be a steam-engine mechanic (around 1800). In 1812 he became chief mechanic at the Killingworth colliery (Northumberland), and in 1815 he invented a new type of safety lamp for miners.

In 1814, Stephenson turned his attention to the construction of steam locomotives. With the aid of J. Steele, a former assistant of R. Trevithick, he built his first locomotive, the Blücher, for a mining railway. In 1815 and 1816 he built two more locomotives of improved design. In 1818, working with N. Wood, Stephenson carried out the first scientific studies on the relationship between the railway’s resistance, on the one hand, and the railway gradient and load, on the other. In 1823 he founded in Newcastle the world’s first plant for the production of steam locomotives. It was here that the locomotive Locomotion (1825) was produced; the engine was intended for the Darlington-Stockton railroad, which itself had been built under Stephenson’s supervision. The plant also turned out the Rocket (1829), built for the railroad between Manchester and Liverpool (1826–30). During construction of the Manchester-Liverpool line, Stephenson became the first to solve certain complex problems of railroad engineering. His solutions involved the use of engineering structures (bridges, viaducts) and of iron rails on rock beds, permitting locomotives of the Rocket type to attain speeds of up to 50 km/hr. The track gauge used by Stephenson (1,435 mm) became the most common for the railroads of Western Europe. In 1836, Stephenson organized a planning office in London that became a scientific and technological center for railroad construction. The designs of Stephenson and his son, Robert, were used to build locomotives that were operated not only in Great Britain but in other countries as well. Stephenson also solved a number of other technical problems related to transportation and industry, and he organized a school for mechanics.