CLERK, SIR DUGALD (1854-1932), Scottish civil en gineer, was born at Glasgow on March 31, 1854. He was educated at the West of Scotland Technical college and the Andersonian college. He invented the Clerk cycle gas engine in 1877, im proving it in 1878 (see GAS ENGINE), and became an authority on internal combustion engines. He also interested himself in motor engineering. During the World War he became director of engineering research to the Admiralty, and until 1919 was a member of the advisory committee for aeronautics to the Air Ministry, and also of the air inventions committee. In 1908 he was elected F.R.S., and in 1917 knighted. His works include The Gas and Oil Engine and many scientific papers.