their prepared positions. The Japanese hoped that as the Americans surrounded and intermingled with the Japanese defensive pockets that the close quarters fighting would prevent the Americans from employing their superior firepower in artillery and close air support. At night, the Japanese planned to infiltrate the American rear areas and interdict their supply lines to prevent the American assault forces from receiving sufficient ammunition and provisions to continue their attacks. The Japanese hoped to delay the Americans long enough for more reinforcements to arrive from Rabaul or elsewhere. Galloping Horse Viewed from overhead with north upward, the Galloping Horse appeared upside down, with Hills 54 and 55 forming the horse's rear legs and Hill 57 forming the front legs. From east to west, Hills 50, 51, and 52 formed the horse's body with the high Hill 53 at the head. Colonel William A. McCulloch—commander of the 27th Regiment—ordered his 1st Battalion to attack Hill 57 and his 3rd Battalion to assault Hills 51 and 52 from Hill 54, which was already in American hands. Defending the Galloping Horse and the nearby fork of the Matanikau were 600 Japanese soldiers from the 3rd Battalion, 228th Infantry Regiment under Major Haruka Nishiyama. The American attack commenced at 05:50 on 10 January with a bombardment by six battalions of artillery and airstrikes by 24 CAF aircraft on suspected Japanese positions in the valley between Hill 57 and the jumping-off point for the 1st Battalion. Beginning their advance at 07:30, the 1st Battalion successfully gained the summit of Hill 57 by 11:40 against light resistance. From Hill 54, the 3rd Battalion's attack route was in the open and dominated by the high ground of Hills 52 and 53. At 06:35, the battalion commenced its assault and occupied Hill 51 without resistance. Continuing its advance, the battalion was stopped by heavy Japanese machine-gun fire short of Hill 52's summit. After an airstrike by six CAF aircraft on Hill 52 and an artillery bombardment, the 3rd Battalion resumed their attack and successfully captured the summit by 16:25, destroying six machine-gun positions and killing about 30 Japanese on the hill. At 09:00 on 11 January, the 3rd Battalion began its attack on Hill 53. The Japanese quickly stopped the American advance with machine-gun and mortar fire. The Americans—who had not received adequate replenishment in water—began to suffer extensive heat casualties. In one platoon, only ten men remained