of Battery Jasper's four 10-inch guns were similarly removed in 1918 for potential use as railway guns; they were never returned to the fort but were replaced with guns from Fort Washington in 1919. Following World War I there were several changes at Fort Moultrie as part of a forcewide partial disarmament of the coast defense system. Battery Bingham's two 4.7-inch Armstrong guns and Battery McCorkle's three 3-inch M1898 guns were removed in 1919–20 as part of a general removal from service of some gun types. Eight of Battery Capron-Butler's mortars were removed and the remaining eight replaced with M1890 mortars on M1896 carriages in 1920. The removal of half the mortars was a forcewide measure to increase the rate of fire by reducing overcrowding of mortar pits during reloading. With the outbreak of World War II in 1939 and the Fall of France in 1940, a comprehensive upgrade of US coastal fortifications was implemented. In the early part of the war the Harbor Defenses of Charleston were garrisoned by the 13th Coast Artillery Regiment of the Regular Army and the 263rd Coast Artillery Regiment of the South Carolina National Guard. The Marshall Military Reservation, a sub-post of Fort Moultrie, was established in the northeast part of Sullivan's Island to accommodate the new batteries. The batteries built during World War II at and near Fort Moultrie were: BCN = Battery Construction Number AMTB = Anti-Motor Torpedo Boat Battery Additionally, a battery of two 16-inch guns designated BCN 125 was proposed for James Island, south of Charleston Harbor, but was never built. The unnamed battery of four 155 mm M1918 towed guns on concrete Panama mounts was established in 1941 to quickly augment Charleston's harbor defenses. The construction of the long-range BCN 520 with 12-inch guns rendered all previous gun defenses in the Charleston area obsolete. BCN 520 was armed with guns removed from Battery Kimble at Fort Travis, Galveston, Texas. Almost all of Fort Moultrie's previous armament was scrapped in 1942, except Battery Thompson's pair of 10-inch guns and Battery Lord's pair of 3-inch guns. The two fixed emplacements of AMTB 2A were built on the former 10-inch Battery Jasper. A Harbor Entrance Control Post (HECP) to coordinate Army and Navy harbor defenses was established at the old fort and has been refurbished as an exhibit. On August 15, 1947, the Army lowered Fort Moultrie's flag for the last time