A large swamp one-half mile north separated the advancing Union army from the Confederate defenders, slowing the Union advance while giving the Confederates cover among small trees and pine. Gen. Henry Wessell’s infantry waded into the swamp to reach the Confederate line in a move the Confederate engineers who designed the defenses had not anticipated. Union soldiers found themselves in mud and water waist deep, with roots that tripped the careless foot and innumerable briars that tore at their clothes. Despite these harsh conditions, Wessells extended and strengthened his line while under heavy Confederate fire. The same swamp that tested the Union troops protected the Confederates, because thick trees and underbrush concealed their positions and made Federal fire inaccurate.