five o'clock in the evening
Hooker had already been joined by two of Sedgwick 's army corps , and had now six army corps at Chancellorsville , while Jackson 's force consisted of 22,000 men . Lee remained with 13,000 at Tabernacle . The latter general had not been attacked , but had continued to make demonstrations against the Federal left , occupying their attention and preventing them from discovering how large a portion of his force had left him . It was at five o'clock in the evening that Jackson 's troops , having gained their position , advanced to the attack . In front of them lay Howard 's division of the Federals , intrenched in strong earthworks covered by felled trees ; but the enemy were altogether unsuspicious of danger , and it was not until with tumultuous cheers the Confederates dashed through the trees and attacked the entrenchment that they had any suspicion of their presence . They ran to their arms , but it was too late . The Confederates rushed through the obstacles , climbed the earthworks , and carried those in front of them , capturing 700 prisoners and five guns .