he joined it full time as a teletype operator. He intended to save enough money to study engineering at the University of Michigan, and attempted to save for tuition. One day he saw an advertisement for a competitive examination for entry to the United States Military Academy at West Point, New York, and he took it. A local man who had graduated from West Point thirty years before gave him a letter of introduction to his local congressman, Representative James Wolcott Wadsworth Jr. of New York's 39th congressional district, who appointed him. Clarke entered West Point on 1 July 1933.He graduated fourth in the class of 1937 on 12 June 1937 and was commissioned as a second lieutenant in the United States Army Corps of Engineers. He was assigned to the 5th Engineer Regiment at Fort Belvoir, Virginia, While at West Point he met and courted Isabel Van Slyke, who worked for the League of Nations Association as a research assistant. They were married in the Chapel of the Most Holy Trinity at West Point in September 1938. They had a son, Pat, and two daughters, Isabel and Nancy. Engineering officers normally earned additional qualification soon after graduation, and he entered Cornell University, where he studied structural and soil engineering. He received his Master of Science degree in civil engineering in September 1940. He was promoted to first lieutenant on 12 June 1940 and captain on 9 September 1940. World War II In August 1940, Clarke assumed command of Company C of the 15th Engineer Battalion, which was based at Fort Bragg, North Carolina, as part of the 9th Infantry Division. In June 1941 he joined the 38th Engineer Regiment at Fort Jackson, South Carolina. After the Japanese attack on Pearl Harbor that brought the United states Into World War II, he attended an abbreviated wartime Command and General Staff College course at the at Fort Leavenworth, Kansas. He then assumed command of the 1st Battalion, 38th Engineer Regiment. In February 1942, his battalion sailed to Ascension Island in the South Atlantic, where he supervised the construction of a military airfield there that became a key refueling point for transatlantic flights to Africa. He was promoted to major on 1 February 1942. His battalion's next assignment was to construct a chain of airbases across Africa, but when he returned to the United States in July 1942 to collect the plans,