Egide Walschaerts

Egide Walschaerts (1820 to 1901) was a Belgian mechanical engineer, best known as the inventor of the Walschaerts valve gear used in steam locomotives. Born in Mechelen, he was recognised as an excellent modeller in 1838 when he showed his work at a local exhibition, and the minister Rogier, who opened it, arranged a place for him at Liège University. In 1842 he joined the Belgian State Railways, reached foreman two years later and was soon made chief superintendent of the works, a post he held for the rest of his life at Mechelen and then at Brussels South. In 1844 he devised a valve gear that adjusts the travel of the valves distributing steam to the cylinders and lets a locomotive be reversed and economise steam. His company did not allow a man of his rank to patent it, so a colleague applied on his behalf, and a locomotive fitted with the gear won a gold medal at the Vienna exhibition of 1873. The gear became almost universal on steam locomotives. In 1874 he also developed a successful version of the Corliss stationary engine.