Colonel Rookes Crompton (1845-1940), British engineer. Crompton was born in Yorkshire. During his army commission in India (1864-75) he developed steam engines and on leaving the army continued with his engineering career. Crompton's brother owned a factory, which Crompton fitted with a Gramme dynamo and arc lamps to make nightworking possible. In 1878, Crompton set up a company to manufacture arc lamps and the Burgin dynamo. The following year, Crompton developed a small version of the Gramme dynamo for use on steam tractor engines. He also used it to power arc lamps at his home. Crompton was a life- long advocate of direct current (DC) supplies.