During the period between the outbreak of World War II in Sept. 1939 and the attack on Pearl Harbor in Dec. 1941, the U.S. became involved in a number of activities to assist Britain, short of war. One of these was the exchange of technical info. between the Royal Navy and the U.S. Navy. Joseph Wellings was the first of the group of officers to go to London and to concentrate on fleet oper. and tactics. His assignment was to observe the fleet at sea and to examine shipboard practices in convoy operations, gunnery and fleet maneuvers, and to report back to the Navy. The documents have been selected and edited to form a coherent, firsthand account of the experiences of an assistant naval attaché and observer of the Royal Navy between Sept. 1940 and June 1941. Ill.