Page:Cambridge Modern History Volume 7.djvu/543

 1863] Grant takes command. Position of Chattanooga. 511 engineer, General W. F. Smith, had devised a plan which, approved by Grant on his arrival, and by his direction executed under Smith's command, once more gave the Federal army control of a much shorter line of supply by the railroad and Tennessee river, and, when the reinforcements under Hooker and Sherman came up, at once changed the relative attitude of the confronting armies, placing the Confederates on the defensive. Only a short time before they had been so confident of success, that Longstreet with his corps of 20,000 was detached to drive Burnside out of eastern Tennessee an order which he attempted to execute by a short siege and assault on Knoxville, ending in his repulse and retreat. It was while his absence diminished Bragg's forces that General Grant personally supervised the preparations and directed the movements which resulted in the battle of Chattanooga on November 23-25, 1863. That attack drove Bragg from the mountain heights which he had so elaborately fortified, into precipitate and disastrous retreat, and permanently opened the gateway by which Sherman in the following summer made his famous march through the heart of Georgia to the sea. The battlefields of Chickamauga and Chattanooga lie in great con- tiguous mountain valleys, parallel with each other, and almost parallel with the general course of the Tennessee river. First on the east lies Chickamauga Valley, watered by Chickamauga Creek, in which, eight miles south-east of Chattanooga, was fought the battle of Chickamauga, on September 19 and 20. This valley is bounded on the west by Missionary Ridge, fifteen miles long, a straight, narrow mountain ridge 500 feet in height, which divides Chickamauga Valley from Chattanooga Valley, watered by Chattanooga Creek and the Tennessee river, the creek flowing northward, the river flowing southward, until they meet at the northern end of Lookout Mountain, which is from 1000 to 1500 feet in height. From this point the river makes a sharp turn, and flows for several miles nearly directly north. Lookout Mountain is three miles south of Chattanooga city, and again divides Chattanooga Valley from Lookout Valley, watered by Lookout Creek. All the creeks mentioned empty into the Tennessee. Chattanooga city lies on the east bank of the Tennessee river, where a great westerly bend of the stream broadens Chattanooga Valley to a width of two miles between the city and Missionary Ridge. Grant's forces, numbering 100,000 effectives, were made up from three different armies; the Army of the Cumberland, formerly commanded by Rosecrans, now by Thomas; the Army of the Tennessee, under command of Sherman ; and two corps from the Army of the Potomac under command of Hooker, lately brought with unusual celerity by rail from Virginia. Hooker's command lay in Lookout Valley, west of Lookout Creek, Thomas' command in the city of Chattanooga, and Sherman's command, with ready pontoon trains, well concealed in the hills west of the Tennessee river.