SAINT LOUIS, March 14, 1862.

E. M. STANTON,

Secretary of War, Washington:

General Bragg is at Memphis, and large re-enforcements are arriving from the South by railroad, to sustain General A. S. Johnston an prevent us from reaching Memphis. If an attack on Mobile is intended, now is the time. The capture of that place would assist us very much here. Moreover, gunboats could then ascend the Alabama River and open its commerce.

H. W. HALLECK,

Major-General.

HEADQUARTERS DEPARTMENT OF THE OHIO,
Nashville, March 14, 1862.

Major-General HALLECK, U. S. A.,

Commanding Department of the Mississippi:

GENERAL: The aggregate force in the Department of the Ohio, in cluding eight regiments which are still with General Grant, is about 101,737; that is, 85,979 infantry, 11,073 cavalry, and 3,948 artillery-twenty-four batteries.

There are about 30,500 sick and absent including the regiments with General Grant, leaving an effective force of about 71,233, exclusive of those eight regiments. It is organized into six divisions and twenty-three brigades, besides some six detached regiments that are employed as guards to bridges, depots, &c., and is employed as follows:

A column of five regiments of infantry, five companies of cavalry, and one field battery, with General Carter, is now at Cumberland Ford, where it has been and is still detained by high water and the difficulty of supplying it over so long a ling of bad road. It had orders to advance on Cumberland Gap, seize and hold it at least, and for its further progress be governed by circumstances in East Tennessee.

A column, composed of five regiments of infantry and eight companies of cavalry, has been operating during the winter against Humphrey Marshall, in the valley of the Big Sandy and on the headquarters of the Kentucky River. Marshall has been defeated and driven out of the State, and I have ordered all of that force, except two regiments of infantry, and two companies of cavalry, stationed at Prestonburg, to Bardstown. I anticipate that it may be desirable or necessary to employ it by the time it can arrive in strengthening the column against Cumberland Gap, so that it can penetrate East Tennessee. There is one regiment in Somerset; I leave it for the present with the same view; one regiment on the Lexington and Covington Railroad, which passes through a troublesome population, and is important to us in supplying the Cumberland Gap column. It will be necessary to keep the regiment on that duty for the present. Three regiments of infantry on the road from here to Louisville. I shall put a regiment of cavalry at Springfield, with small detachments at certain points on the railroads at and this side of Bowling Green.

The whole of the remaining force I am concentrating at this point to operate against the enemy in front. It will consist of about 55,000 men of all arms present for duty, organized into eighteen brigades and six divisions; at present the effective force is about 50,000.

When you consider the importance of this State and its exposure to invasion by the various railroad routes, you will see that the force is