WASHINGTON,

March 20, 1863.

Major General U. S. GRANT,

Commanding Department of the Tennessee:

GENERAL: Your letter of March 7 is received. It is the first communication from you for some time which has reached here. It is very desirable that you keep us advised of your operations, in order that proper instructions may be sent to General Banks, General Rosecrans, &c. Send telegrams to Memphis by every opportunity.

In operating by the Yazoo, you have, no doubt, fully considered the advantages and dangers of the expedition. Our information here on that subject is very limited and unsatisfactory. There is one point, however, which has been discussed, and to which I would particularly call your attention; it is the danger, on the fall of the water in the Mississippi, of having your steamers caught in the Upper Yazoo, so as to be unable to extricate them. In the present scarcity of steamers on the western rivers, this would be a very serious loss. Another danger is, that the enemy may concentrate a large force upon the isolated column of McPherson without your being able to assist him. I mention these matters in order that you may give them your full attention.

When the operations of an army are directed to one particular object it is always dangerous to divide forces. All accessories should be sacrificed for the sake of concentration. The great object on your line now is the opening of the Mississippi River, and everything else must tend to that purpose. The eyes and hopes of the whole country are now directed to your army. In my opinion, the opening of the Mississippi River will be to us of more advantage than the capture of forty Richmonds. We shall omit nothing which we can do to assist you.

Permit me to repeat the importance of your frequently advising me by telegraph from Memphis.

Very respectfully, your obedient servant,

H. W. HALLECK,

General-in-Chief.

WAR DEPARTMENT,

Washington,

March 24, 1863.

Major-General GRANT,

Before Vicksburg, MISS.:

I must again call your attention to the importance of your not retaining so many steamers in the Mississippi. It is absolutely necessary that a part of these boats be returned. We cannot otherwise supply our armies in Tennessee and Kentucky. This matter must be attended to without delay.

H. W. HALLECK,

General-in-Chief.

NEAR Vicksburg, MISS.,

March 24, 1863.

VIA CAIRO, ILL.,

March 31.

Major General H. W. HALLECK,

General-in-Chief:

At last accounts Yazoo Pass expedition was yet at Greenwood. Admiral Porter and Sherman are attempting to get into the Yazoo below Yazoo City. No news from them for several days. Farragut holds the river above Port Hudson.

U. S. GRANT,

Major-General.