Immediately after the ceremony of surrender was over Sherman marched away with a strong force to find and fight Johnston's army. But that general, shunning the conflict, moved so far southward into Mississippi that pursuit was imprudent during the hot season. While Grant was finishing the siege of Vicksburg, General Banks was besieging Port Hudson, which lay at the southern end of the rebel section of the river. The fall of the northern post rendered the southern one untenable, and it was surrendered on July 9. Henceforth the great river was a safe roadway for unarmed craft flying the stars and stripes. It is time now to go back to Tennessee. By the close of the first week in July, 1863, the Confederate force was established in Chattanooga, and thus the hostile armies were "placed back in the relative positions occupied by them prior to Bragg's advance into Kentucky, a little less than one year previous." But though the Southern general had reached his present position by a retreat at the end of a disappointing enterprise, the issue of final success was still an open one between him and Rosecrans, with many advantages on his side. He had a large army in the heart of a mountainous region, with the opportunity to post it in positions which ought to be impregnable. Moreover, he received fresh troops under Johnston; and later the inaction of Meade in Virginia encouraged Lee to send to him a considerable force under Longstreet, himself no small reinforcement. These arrived just on the eve of the impending battle. Meantime Mr. Lincoln was sorely exercised at his inability to make his generals carry out his plans. He desired that Burnside should move down from the north and unite with Rosecrans, and that then the combined force should attack Bragg promptly. But Rosecrans lay still for about six weeks, to repair losses and fatigue, and again played the part of the restive steed, responding to the President's spur only with fractious kickings. It was August 16 when he moved, but then he showed his usual ability in action. The march was difficult; yet, on September 6, he had his whole force across the Tennessee and in the mountains south of Chattanooga. Burnside, meanwhile, had advanced to Knoxville, but had stopped there, and was now, greatly to Mr. Lincoln's bewilderment and annoyance, showing activity in every direction except precisely that in which he was directed to move.