advanced on the springs at Apache Pass in the same manner, leaving Cremony with the guard detachment. Battle At noon on July 15, Roberts' detachment had just entered Apache Pass. After traveling about two-thirds of the way through, his force was attacked by about 500 Apache warriors led by Mangas Coloradas and Cochise (Geronimo claimed to have fought in this battle but this has not been confirmed). The Union soldiers were not in a good situation. The infantrymen had walked dozens of miles across the hot Arizona desert, heading for the spring at Apache Pass, which was now blocked to them by the well-armed Chiricahua warriors. Low on water, and realizing a retreat back to Tucson without water could cost him many men, Roberts chose to fight. The Apaches had thrown up defenses, which consisted of several breastworks made of stone. They had also surprised the invaders with an ambush, waiting until the soldiers came within 30–80 yards of their positions before opening fire. Behind almost every mesquite tree and boulder hid an Apache with his rifle, six-shooter and knife. At first the Union troops could barely see their attackers. After a few minutes of intense combat Roberts ordered retreat, and his force withdrew to the mouth of Apache Pass. His men regrouped and unlimbered the mountain howitzers for an advance against the Apaches. This was one of the first times the United States Army had been able to use artillery against the Indians in the Southwest. Roberts ordered his infantry to take the hills overlooking the pass, while he remained in the pass to direct the artillery support. The skirmishers moved forward, where they were able to take cover in an abandoned Butterfield Overland Mail station. The soldiers were now about 600 yards from the spring. Overlooking the spring were two hills, one on the east, the other on the south. The Apache riflemen behind the breastworks on the hills were delivering a deadly fire against the attackers. Roberts advanced with his howitzers and had them open fire. Their effectiveness was limited by the fact that they were 300–400 feet below the Apache defenses. Roberts moved his guns ahead to a better position, all the time under heavy fire. Once the guns were in effective range, the artillery opened fire in earnest. The Apaches held their positions until nightfall, when they fled, allowing the Union troops to reach the