and ordered to Tennessee as a reinforcement for William Rosecrans, besieged in Chattanooga. The two corps were placed under the command of Maj. Gen. Joseph Hooker. Arriving in Tennessee, Geary's Division moved to the front, while Williams's Division was stationed along the railroad from Murfreesboro to Bridgeport. Geary pushed on in order to effect a junction with the beleaguered army at Chattanooga. On the night of October 27, his division bivouacked in Lookout Valley, in an advanced and isolated position, where he was attacked at midnight by a part of James Longstreet's command. But Geary had taken proper precautions against surprise, and Longstreet was repulsed, Geary receiving in this affair a prompt and gallant support from part of the XI Corps. General George H. Thomas, commanding the Army of the Cumberland, stated in his official report that "the repulse by Geary's Division of greatly superior numbers who attempted to surprise him, will rank among the most distinguished feats of arms of this war." The midnight Battle of Wauhatchie was followed in the next month by the brilliant victory at Lookout Mountain, where the 2nd Division fought its famous "battle above the clouds". Geary was assisted in this engagement by Walter C. Whitaker's Brigade of the IV Corps. One of Whitaker's regiments, the 8th Kentucky, was the first to plant its flag on the summit of the mountain. Redesignation In April 1864, the designation of the corps was changed to that of the XX Corps. Generals Williams and Geary still retained command of their divisions and the men still wore their XII Corps badge. This badge (a five-pointed star, or pentagram) was adopted by the reorganized corps. The new organization was formed by the consolidation of the XI and XII corps, to which was added some minor commands. This action of the War Department was based on the small sizes of the two corps: the XI had been extremely damaged at Gettysburg and the XII had always been the smallest in the army. Nonetheless, the soldiers of the XII Corps were very upset at the loss of their original corps identity. Upon the discontinuance of the XII Corps, General Slocum was assigned to the command of the District of Vicksburg, but resumed the corps command—of the XX Corps—during the Atlanta Campaign, General Hooker having been relieved. Slocum afterwards commanded the Army of Georgia while on the March to the Sea and