General Grant arrived at Chattanooga on October 23, and began at once to carry out the plans that had been formed for opening the shorter or river road to Bridgeport. This object was successfully accomplished by the moving of Hooker’s command to Rankin’s and Brown’s ferries in concert with a force from the Army of the Cumberland which was directed on the same points, so by the 27th of October direct communication with our depots was established. The four weeks which followed this cheering result were busy with the work of refitting and preparing for offensive operations as soon as General Sherman should reach us with his troops from West Tennessee. During this period of activity the enemy committed the serious fault of detaching Longstreet’s corps—sending it to aid in the siege of Knoxville in East Tennessee—an error which has no justification whatever, unless it be based on the presumption that it was absolutely necessary that Longstreet should ultimately rejoin Lee’s army in Virginia by way of Knoxville and Lynchburg, with a chance of picking up Burnside en route. Thus depleted, Bragg still held Missionary Ridge in strong force, but that part of his line which extended across the intervening valley to the northerly point of. Lookout Mountain was much attenuated.
By the 18th of November General Grant had issued instructions covering his intended operations. They contemplated that Sherman’s column, which was arriving by the north bank of the Tennessee, should cross the river on a pontoon bridge just below the mouth of Chickamauga Creek and carry the northern extremity of Missionary Ridge as far as the railroad tunnel; that the Army of the Cumberland —the centre—should co-operate with Sherman; and that Hooker with a mixed command should continue to hold Lookout Valley and operate on our extreme right as circumstances might warrant. Sherman crossed on the 24th to perform his alloted part of the programme, but in the meantime Grant becoming impressed with the idea that Bragg was endeavoring to get away, ordered Thomas to make a strong demonstration in his front, to determine the truth or falsity of the information that had been received.