[Inclosure.]

HEADQUARTERS DEPARTMENT OF THE GULF,
Grand Ecore, La., April 17, 1864.

Effective aggregate for duty of troops at the several posts and stations in the Department of the Gulf:

Rio Grande ............................................ 3,000

Pass Cavallo .......................................... 1,227

Pensacola ............................................. 1,500

Key West .............................................. 791

New Orleans ........................................... 750

Baton Rouge ........................................... 885

Port Hudson ........................................... 6,809

The above statement is as accurate as the imperfect material at hand will admit of making.

GRAND ECORE, LA., April 18, 1864.

The rebel army of the West, 25,000 strong, is in our front. The withdrawal of my command without the destruction or dispersion of this force will enable them to commence offensive operations in Missouri, Arkansas, or Louisiana, or against each of these States successively. It will require the whole force, more than a hundred thousand strong, west of the Mississippi to defend these States against the successive attacks of this force, and it will be difficult to concentrate any considerable force from the army on the Mississippi for operations against Mobile with such an active and powerful enemy in our rear. The destruction or dispersion of this army, the desolation of the country it occupies, and the destruction of the land or water transportation will make it impossible for a reorganization or any movement against the States bordering upon the Mississippi, and enable a strong force of our troops to commence an immediate and successful campaign against Mobile. This result is certain to be accomplished within thirty days, if only a portion of Steele's command could operate with me upon this line, independent of the river and of the navy. This campaign is not of my suggestion, but its results are so much more important than I first thought, and so certain to be attained, that I hesitate to withdraw my forces without positive orders, and I send this dispatch by telegraph, knowing that a reply can be telegraphed me in return without delay. Important as the campaign is, I would not embarrass the greater operations of the army in the East.

N. P. BANKS,

Major-General, Commanding.

Lieutenant General U. S. GRANT.

ALEXANDRIA, LA., April 30, 1864.

My dispatch of the 24th gave you information of the arrival of my command at Natchitoches on the evening of the 20th instant, and also that an immediate advance upon the objective point of the expedition was in contemplation, upon a line differing somewhat from that upon which we had retired, with a view to render my column less dependent upon the river. The rapidly falling river, however,