On May 8, 1846, Taylor's army met the Mexican army of Mariano Arista in the Battle of Palo Alto. Duncan's battery was posted on the American left flank while Ringgold's battery was on the right. In the center stood two heavy 18-pounder cannons. Opposing the 2,228 Americans were 3,826 Mexicans with two 8-pounders and at least six 4-pounders. Duncan's and Ringgold's batteries deployed in front of the American infantry line and about from the Mexican defenders. Though many rounds overshot their targets, the effect of the American artillery fire was murderous. Meanwhile, the U.S. infantrymen were largely spectators to the artillery duel. Late in the afternoon, the Mexicans launched an infantry and cavalry attack against the American left wing, but it was repulsed by Duncan's battery. Though the battle ended inconclusively, the Americans lost only five killed, 43 wounded, and two missing. Ten more later died of their wounds including Ringgold who was struck in both legs by a 4-pounder shot. Arista reported 102 killed in his official report, but privately admitted losing 252 men killed.
