To carry out this plan, Sherman was to cross the Tennessee at Brown’s Ferry and move east of Chattanooga to a point opposite the north end of Mission Ridge, and to place his command back of the foot-hills out of sight of the enemy on the ridge.  There are two streams called Chickamauga emptying into the Tennessee River east of Chattanooga—­North Chickamauga, taking its rise in Tennessee, flowing south, and emptying into the river some seven or eight miles east; while the South Chickamauga, which takes its rise in Georgia, flows northward, and empties into the Tennessee some three or four miles above the town.  There were now one hundred and sixteen pontoons in the North Chickamauga River, their presence there being unknown to the enemy.

At night a division was to be marched up to that point, and at two o’clock in the morning moved down with the current, thirty men in each boat.  A few were to land east of the mouth of the South Chickamauga, capture the pickets there, and then lay a bridge connecting the two banks of the river.  The rest were to land on the south side of the Tennessee, where Missionary Ridge would strike it if prolonged, and a sufficient number of men to man the boats were to push to the north side to ferry over the main body of Sherman’s command while those left on the south side intrenched themselves.  Thomas was to move out from his lines facing the ridge, leaving enough of Palmer’s corps to guard against an attack down the valley.  Lookout Valley being of no present value to us, and being untenable by the enemy if we should secure Missionary Ridge, Hooker’s orders were changed.  His revised orders brought him to Chattanooga by the established route north of the Tennessee.  He was then to move out to the right to Rossville.

Hooker’s position in Lookout Valley was absolutely essential to us so long as Chattanooga was besieged.  It was the key to our line for supplying the army.  But it was not essential after the enemy was dispersed from our front, or even after the battle for this purpose was begun.  Hooker’s orders, therefore, were designed to get his force past Lookout Mountain and Chattanooga Valley, and up to Missionary Ridge.  By crossing the north face of Lookout the troops would come into Chattanooga Valley in rear of the line held by the enemy across the valley, and would necessarily force its evacuation.  Orders were accordingly given to march by this route.  But days before the battle began the advantages as well as the disadvantages of this plan of action were all considered.  The passage over the mountain was a difficult one to make in the face of an enemy.  It might consume so much time as to lose us the use of the troops engaged in it at other points where they were more wanted.  After reaching Chattanooga Valley, the creek of the same name, quite a formidable stream to get an army over, had to be crossed.  I was perfectly willing that the enemy should keep Lookout Mountain until we got through with the troops