 Barnes's brigade was ordered to relieve a brigade of the IX Corps which had made a charge on the stone wall along Marye's Heights and become pinned down by Confederate fire.By the time they formed up battle lines on the open slope in front of Marye's Heights, the 22nd was under intense artillery fire from the Confederates.According to the regimental historian, "the men instinctively turned their sides to the storm" of bullets, shot and shell as they advanced and casualties were heavy.