WASHINGTON,

April 2, 1863.

Major General U. S. GRANT,

before Vicksburg:

GENERAL: Your dispatch of March 17 and also your telegrams of March 24 and 25 were received yesterday.

While working upon the canal, the DIVISION of your forces into several eccentric operations may have been very proper for the purpose of reconnoitering the country; but it is very important that, when you strike any blow, you should have your troops sufficiently concentrated to make that blow effective. The DIVISION of your army into small expeditions destroys your strength, and, when in the presence of an enemy, is very dangerous.

What is most desired, and your attention is again called to this object, is that your forces and those of General Banks should be brought into co-operation as early as possible. If he cannot get up to co operate with you on Vicksburg, cannot you get troops down to help him on Port Hudson, or, at least, can you not destroy Grant Gulf before it becomes too strong?

I know that you can judge of these matters there much better than I can here; but as the President, who seems to be rather impatient about matters on the Mississippi, has several times asked me these questions, I repeat them to you.

As the season when we can do very little on the Lower Mississippi is rapidly advancing, I hope you will push matters with all possible dispatch.

Very respectfully, your obedient servant,

H. W. HALLECK,

General-in-Chief.

HEADQUARTERS DEPARTMENT OF THE TENNESSEE,
Before Vicksburg,

April 4, 1863.

Major General H. W. HALLECK,

General-in-Chief, Washington, d. C.:

GENERAL: By information from the south, by way of Corinth, I learn that the enemy in front of Rosecrans have been re-enforced from Richmond, Charleston, Savannah, Mobile, and a few from Vicksburg. They have also collected a cavalry force of 20,000 men. All the bridges eastward from Savannah and north from Florence are being rapidly repaired. Chalmers is put in command of Northern Mississippi, and is collecting all the Partisan Rangers and loose and independent companies of cavalry that have been operating in this department. He is now occupying the line of the Tallahatchee. This portends preparation to attack Rosecrans, and to be able to follow up any success with rapidly, also to make a simultaneous raid into WEST Tennessee, both from Northern Mississippi and by crossing the Tennessee River. To counteract this, Admiral Porter has consented to send the Marine Brigade up the Tennessee River to co-operate with General Dodge at Corinth. I have also ordered an additional regiment of cavalry from Helena into WEST Tennessee. I inclose with this a letter from Major-General Hurlbut, giving a program, which he wishes to carry out, and so much of it as to drive the enemy from the Tallahatchee and cutting the roads where they have been repaired, I think can be successfully executed. I will instruct him not to scatter his forces so as to risk losing them. I have placed one DIVISION of troops on Deer Creek, with communication back to the Mississippi River, just above Lake Washington. The object of