Sherman was fully aware that he would have many advantages in pushing after Hood at once, but besides his army's real need of rest, he was clear in his judgment that he must, at this stage of affairs, prepare for a campaign on a great scale to be continued through the winter till great results should be achieved. If the line of operations was to be extended toward Mobile, as was contemplated by General Grant at the opening of the campaign, or if Hood should retreat toward the east, in either case he must make Atlanta a fortified base. Experience had proven that his long line of communications was liable to interruption, and would be still more so as he penetrated further into Georgia. He must have a well-supplied and well-protected depot in the same relations to the next forward movement that Chattanooga had been to the campaign just finished. He wanted to get his share of the drafted men under the conscription law now in operation, to fill up the places of regiments whose terms had expired, and to be assured that Canby from New Orleans would co-operate in a settled plan. He was already revolving in his mind other problems which Hood might possibly open for solution; but the probability seemed strong that the Confederate army would bar the way to his advance, and must be beaten and driven back again. His first task, therefore, was to prepare Atlanta for his uses. "I want it," he said, "a pure Gibraltar, and will have it so by October 1st." [Footnote: Dispatch to Halleck, September 9th. See also that of September 4th, in which his ideas were fully outlined. Official Records, vol. xxxviii. pt. v. pp. 794, 839.] This use of the town made it necessary to remove the resident citizens, sending north those who were loyal and ordering south those who adhered to the Confederacy. As a fortified depot must be ready for a siege, trade and free intercourse with the surrounding country could not go on. The inhabitants, therefore, would be dependent on the army for food, their industries must cease, and it was more merciful to them, as well as a military necessity, to send them away. [Footnote: Sherman to Hood, _Id_., p. 822.]