I left Memphis for my new field without delay and reached Corinth on the fifteenth of the month. General Halleck remained until the seventeenth of July; but he was very uncommunicative, and gave me no information as to what I had been called to Corinth for. When General Halleck left to assume the duties of general-in-chief I remained in command of the District of West Tennessee. Practically I became a department commander because no one was assigned to that position over me, and I made my reports direct to the General-in-chief; but I was not assigned to the position of department commander until the twenty-fifth of October. General Halleck, while commanding the Department of the Mississippi, had had control as far east as a line drawn from Chattanooga north. My district only embraced West Tennessee and Kentucky west of the Cumberland river. Buell, with the Army of the Ohio, had as previously stated, been ordered east towards Chattanooga, with instructions to repair the Memphis and Charleston railroad as he advanced. Troops had been sent North by Halleck along the line of the Mobile and Ohio railroad to put it in repair as far as Columbus. Other troops were stationed on the [Mississippi Central] railroad from Jackson, Tennessee, to Grand Junction, and still others on the road west to Memphis. The remainder of the magnificent army of 120,000 men which entered Corinth on the thirtieth of May, had now become so scattered that I was put entirely on the defensive in a territory whose population was hostile to the Union. One of the first things I had to do was to construct fortifications at Corinth better suited to the garrison that could be spared to man them. The structures that had been built during the months of May and June were left as monuments to the skill of the engineer, and others were constructed in a few days, plainer in design, but suited to the command available to defend them. In brief Halleck had completely thrown away one of the most brilliant opportunities of the war. He had found an army of 120,000 men, flushed with victory and full of spirit, concentrated at a point in the center of the Confederacy, from which it was not only possible but easy to advance in overwhelming force in any direction, while the inflow of recruits at that time was great enough to make good and even to double the losses that battle might involve. On the other hand the Confederates had lost so heavily at Shiloh that they did not venture to make a stand in their intrenchments at Corinth, even though Halleck's extraordinary dilatoriness gave them seven weeks of precious time in which to recruit their army, strengthen their defenses and receive reinforcements of 17,000 seasoned and veteran troops that were presently sent to them.