General George T. Anderson's brigade from Jenkins' division was ordered to attack the Union trenches east of Fort Sanders. If the assault captured the fort, Law was supposed to attack the south bank defenses. At 10:00 pm, McLaws advanced his skirmish lines to within of Fort Sanders. The operation was successful, but it alerted the Federals that the fort was about to be assaulted. McLaws' two assault columns of about 2,400 men formed about to the northwest of the fort. The infantry assault began at 6:20 am after a 20 minute artillery bombardment. The front ranks were knocked over when they reached the wire entanglement, but got up again and surged forward. When the Confederates reached the ditch, it was a rude surprise. The Union parapet loomed above the bottom of the deep ditch. To reach the parapet, the attackers had to climb a slippery clay slope of about 70° while braving intense fire. During the attack, Union officers ordered their soldiers into the fort to assist the garrison. Benjamin lit the fuses of his battery's artillery shells and threw them into the ditch among the crowded Confederates. Union infantry also poured flanking fire into the ditch from the east. Anderson's attack was bungled; it was made in the wrong direction and sustained only 37 casualties. The assault failed and cost the Confederates 129 killed, 458 wounded, and 226 missing, for a total of 813 casualties. Historian Earl J. Hess stated that Union casualties were only about 20 men inside the fort and 30 men outside. According to Jacob Dolson Cox, there were 43 Union casualties. Ruff was killed and so was his successor, Colonel Henry P. Thomas of the 16th Georgia Infantry. Colonel Kennon McElroy of the 13th Mississippi Infantry was also killed. Colonel Edward Ball of the 53rd Georgia Infantry, Lieutenant Colonel John Fiser of the 17th Mississippi Infantry, and Major Joseph Hamilton of Phillip's Georgia Legion were wounded. Perhaps 30 minutes after the assault failed, Longstreet received official news that Grant badly defeated Bragg at the Battle of Missionary Ridge on November 25, 1863. Burnside allowed a truce so that the Confederates could recover their dead and wounded. Some defenders belonging to the IX Corps regarded the battle as revenge for the Federal defeat at the Battle of Fredericksburg. Relief After the debacle at Fort Sanders, Longstreet decided to besiege Burnside for as long as possible. He