|From Hauser's Ridge Map|
Their position atop Nicodemus Heights rendered ineffective by the West Woods as Federal Soldiers closed in on the Dunker Church, Pelham’s batteries limbered up and redeployed on Hauser’s Ridge to the south. The western edge of the West Woods hugs the base of the ridge, which rises steadily to its crest perhaps 200-300 yards farther west. Here, as if by design, the rebels deployed their guns directly in the path of the advance of Sedgwick’s Division of the Second Corps.
Edwin “Bull” Sumner led Sedgwick’s men forward to clear the West Woods. This accomplished, he planned a massive left wheel by the entire division to clear the northern part of the battlefield all the way to the town of Sharpsburg. Initially, the advance met with little resistance. As they emerged from the tree line, they met a storm of shot and shell from the batteries atop Hauser’s ridge. Remnants of Jackson’s Division joined in to halt the Federal advance. This was the first of several shocks that would virtually destroy Sedgwick’s Division as a fighting force for the balance of the battle.
Sedgwick’s lead brigade under Gorman faltered under a withering fire from the ridge in their. The 1st Minnesota, Gorman’s right flank regiment, suffered 118 casualties within minutes. In the center, the 15th Massachusetts regiment lost 348 men, over 50% of its strength. The commander of the 15th, Lt. Colonel John W. Kimball, reported twice driving off the batteries in his front before the left of the brigade collapsed under the weight of the flank attack by McLaws’s Division.
While the artillery fire was not the decisive factor in Sedgwick’s repulse, the rebel guns on Hauser’s ridge stalled the Federal advance and amplified the devastation of McLaws’s slashing attack from the south. Here, as on Nicodemus Heights farther north, Confederate artillerists established local superiority, providing critical support to their outnumbered infantry in tactical situations where their Federal counterparts lacked effective artillery support. Both positions were outside the range of McClellan’s large caliber rifles that so dominated the area around the Dunker Church, the “artillery hell” described by S.D. Lee, commander of the rebel artillery battalion assigned there. Pelham and other Confederate artillerists used this advantage to provide aggressive and effective support at the right place and time, materially assisting Jackson’s troops in their defensive efforts on that bloody morning.