When the Federals reached Burkittsville around noon, the Confederate artillery opened up. In Burkittsville, while under artillery fire, Franklin assembled his troops into three columns. At 3 p.m., after a delay of nearly 3 hours, the VI Corps finally began its assault. The reason for the delay has never been ascertained, but it would prove costly. The Union advance was slow and steady, supported by artillery. Their superior numbers quickly overwhelmed Mahone's regiments and the cavalry along with the artillery on the slopes of the mountain. The retreating Confederates were briefly rallied at the summit by General Cobb, but an oncoming charge by the First New Jersey Brigade (the first four New Jersey regiments) was too much. Once the VI Corps reached the summit they drove the Confederates from their positions, inflicting heavy casualties, in just fifteen minutes of fighting. Confederate losses included an aide to Cobb, John Basil Lamar and Jefferson M. Lamar, the younger brother of Lucius Q. C. Lamar. Both Lamars were related to Cobb's wife the former Mary Ann Lamar.