Staff College Men Watch On Amphibious Exercise -- Frogmen, having attached mines to an underwater obstruction, comes ashore to light the fuses as they prepare to demolish them. Students of the Staff College, Camberley, yesterday saw a comprehensive demonstration of amphibian warfare given by the Navy, Army and Royal Marines at Eastney Beach, Portsmouth. Amphibian tanks, infantry, assault craft and swimming amphibians took part. Object of the demonstration was to show a sequence of events in a combined assault. July 15, 1948. (Photo by Fox).