The Second, commanded by Brigadier-General Morgan L. Smith, was composed of two brigades, led by Brigadier-Generals Giles A. Smith and J. A. J. Lightburn.
The Third, commanded by Brigadier-General J. M. Tuttle, was composed of three brigades, led by Brigadier-Generals J. A. Mower and R. P. Buckland, and Colonel J. J. Wood (of the Twelfth Iowa).
The Fourth, commanded by Brigadier-General Hugh Ewing, was composed of three brigades, led by Brigadier-General J. M. Corse, Colonel Loomis (Twenty-sixth Illinois), and Colonel J. R. Cockerill (of the Seventieth Ohio).
On the 22d day of September I received a telegraphic dispatch from General Grant, then at Vicksburg, commanding the Department of the Tennessee, requiring me to detach one of my divisions to march to Vicksburg, there to embark for Memphis, where it was to form a part of an army to be sent to Chattanooga, to resnforce General Rosecrans. I designated the First Division, and at 4 r. as. the same day it marched for Vicksburg, and embarked the neat day.
On the 23d of September I was summoned to Vicksburg by the general commanding, who showed me several dispatches from the general-in- chief, which led him to suppose he would have to send me and my whole corps to Memphis and eastward, and I was instructed to prepare for such orders. It was explained to me that, in consequence of the low stage of water in the Mississippi, boats had arrived irregularly, and had brought dispatches that seemed to conflict in their meaning, and that General John E. Smith's division (of General McPherson's corps) had been ordered up to Memphis, and that I should take that division and leave one of my own in its stead, to hold the line of the Big Black. I detailed my third division (General Tuttle) to remain and report to Major- General McPherson, commanding the Seventeenth Corps, at Vicksburg; and that of General John E. Smith, already started for Memphis, was styled the Third Division, Fifteenth Corps, though it still belongs to the Seventeenth Army Corps. This division is also composed of three brigades, commanded by General Matthias, Colonel J. B. Raum (of the Fifty-sixth Illinois), and Colonel J. I. Alexander (of the Fifty-ninth Indiana).
The Second and Fourth Divisions were started for Vicksburg the moment I was notified that boats were in readiness, and on the 27th of September I embarked in person in the steamer Atlantic, for Memphis, followed by a fleet of boats conveying these two divisions. Our progress was slow, on account of the unprecedentedly low water in the Mississippi, and the scarcity of coal and wood. We were compelled at places to gather fence-rails, and to land wagons and haul wood from the interior to the boats; but I reached Memphis during the night of the 2d of October, and the other boats came in on the 3d and 4th.
On arrival at Memphis I saw General Hurlbut, and read all the dispatches and letters of instruction of General Halleck, and therein derived my instructions, which I construed to be as follows:
To conduct the Fifteenth Army Corps, and all other troops which could be spared from the line of the Memphis & Charleston Railroad, to Athens, Alabama, and thence report by letter for orders to General Rosecrans, commanding the Army of the Cumberland, at Chattanooga; to follow substantially the railroad eastward, repairing it as I moved; to look to my own line for supplies; and in no event to depend on General Rosecrans for supplies, as the roads to his rear were already overtaxed to supply his present army.