The crew of SS Stanley Park's 4-inch gun, dressed for hot tropical weather, practice with their weapon.

The heaviest weapon aboard the ship, the 4-inch gun was intended for use against enemy surface raiders or surfaced submarines, as well as against enemy aircraft. While submarines posed the most significant enemy threat to Allied merchant ships, surface raiders, often disguised as friendly or neutral merchant vessels, were also a danger. Aircraft attacks were also a threat for much of the war, particularly in the waters around the United Kingdom and off the European coast, from the Mediterranean to the Arctic.

George Metcalf Archival Collection
CWM 19860141-051