William Joseph Still was an English engineer. He was born at Reigate on 17 August 1870. In 1884, he went to Canada to work for a firm of electric vehicle manufacturers. In 1894, he returned to England, where he invented a double-acting diesel-steam engine in which waste heat from the cylinder jacket and the exhaust was used to produce steam to assist the diesel engine. This is covered by U.S. patent 1230617 of 1917.[1] Still also invented the Still heat-transmitting tube which was used in refrigeration plant.[2]