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 25th 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 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 30th 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.

I disposed the troops belonging to the district in conformity with the situation as rapidly as possible.  The forces at Donelson, Clarksville and Nashville, with those at Corinth and along the railroad eastward, I regarded as sufficient for protection against any attack from the west.  The Mobile and Ohio railroad was guarded from Rienzi, south of Corinth, to Columbus; and the Mississippi Central railroad from Jackson, Tennessee, to Bolivar.  Grand Junction and La Grange on the Memphis railroad were abandoned.

South of the Army of the Tennessee, and confronting it, was Van Dorn, with a sufficient force to organize a movable army of thirty-five to forty thousand men, after being reinforced by Price from Missouri.  This movable force could be thrown against either Corinth, Bolivar or Memphis; and the best that could be done in such event would be to weaken the points not threatened in order to reinforce the one that was.  Nothing could be gained on the National side by attacking elsewhere, because the territory already occupied was as much as the force present could guard.  The most anxious period of the war, to me, was during the time the Army of the Tennessee was guarding the territory acquired by the fall of Corinth and Memphis and before I was sufficiently reinforced to take the offensive.  The enemy also had cavalry operating