The moment I received reliable information of the departure of Longstreet’s corps from the Army of the Potomac, I ordered forward to General Rosecrans every available man in the Department of the Ohio, and again urged General Burnside to move to his assistance.  I also telegraphed to Generals Hurlbut, Sherman, and yourself, to send forward all available troops in your department.  If these forces had been sent to General Rosecrans by Nashville, they could not have been supplied; I therefore directed them to move by Corinth and the Tennessee River.  The necessity of this has been proved by the fact that the reinforcements sent to him from the Army of the Potomac have not been able, for the want of railroad transportation, to reach General Rosecrans’s army in the field.

In regard to the relative strength of the opposing armies, it is believed that General Rosecrans when he first moved against Bragg had double, if not treble, his force.  General Burnside, also, had more than double the force of Buckner; and, even when Bragg and Buckner united, Rosecrans’s army was very greatly superior in number.  Even the eighteen thousand men sent from Virginia, under Longstreet, would not have given the enemy the superiority.  It is now ascertained that the greater part of the prisoners parolled by you at Vicksburg, and General Banks at Port Hudson, were illegally and improperly declared exchanged, and forced into the ranks to swell the rebel numbers at Chickamauga.  This outrageous act, in violation of the laws of war, of the cartel entered into by the rebel authorities, and of all sense of honor, gives us a useful lesson in regard to the character of the enemy with whom we are contending.  He neither regards the rules of civilized warfare, nor even his most solemn engagements.  You may, therefore, expect to meet in arms thousands of unexchanged prisoners released by you and others on parole, not to serve again till duly exchanged.

Although the enemy by this disgraceful means has been able to concentrate in Georgia and Alabama a much larger force than we anticipated, your armies will be abundantly able to defeat him.  Your difficulty will not be in the want of men, but in the means of supplying them at this season of the year.  A single-track railroad can supply an army of sixty or seventy thousand men, with the usual number of cavalry and artillery; but beyond that number, or with a large mounted force, the difficulty of supply is very great.

I do not know the present condition of the road from Nashville to Decatur, but, if practicable to repair it, the use of that triangle will be of great assistance to you.  I hope, also, that the recent rise of water in the Cumberland and Tennessee Rivers will enable you to employ water transportation to Nashville, Eastport, or Florence.

If you reoccupy the passes of Lookout Mountain, which should never have been given up, you will be able to use the railroad and river from Bridgeport to Chattanooga.  This seems to me a matter of vital importance, and should receive your early attention.