WASHINGTON, December 20, 1862.

Major-General CURTIS:

You can use the forces at Helena as you propose. The troops which join the Mississippi expedition will be temporarily under the general direction of General Grant.

H. W. HALLECK,

General-in-Chief.

HEADQUARTERS DEPARTMENT OF THE MISSOURI,
Saint Louis, Mo., December 20, 1862.

Rear-Admiral DAVID D. FOSTER:

DEAR SIR: I am again informed that the Arkansas is rising, and I am sure the White River must be, as the tributaries are flush.

I have quite an army near Van Buren, and wish, if possible, to unite that force with the Helena force, or I want to occupy the rebel force at Little Rock, so as to prevent it from massing against General Blunt, who is in Northwestern Arkansas, near Van Buren.

The least move toward Little Rock will be an advantage, and something may be done without impairing the main move down the river, which we must regard as primary. My object in writing is to ask your co-operation, by furnishing light-draught gunboats to go up either the Arkansas or White River, or both, to help clean them out and frighten the rebels out of Northern Arkansas. I do not expect to finish the job until the force which goes down to Vicksburg may be able to return, but a commencement toward Little Rock will do good, and may deceive the rebels in regard to your down-river move.

General Gorman will confer with you.

I am, sir, very respectfully, your obedient servant,

SAML. R. CURTIS,

Major-General.

HEADQUARTERS DEPARTMENT OF THE MISSOURI,
Saint Louis, December 20, 1862.

Brigadier General W. A. GORMAN, Helena, Ark.:

GENERAL: I want the interior move toward Little Rock made immediately, but, as I have promised the down-river expedition certain aid, it is to be subordinate to that. Twelve thousand are to go down river; the remainder must hold Helena and move west. I will send down forces to augment the strength. You will move cautiously interior, but try to occupy the attention of Holmes, so as to prevent him from sending his force to Hindman. For this purpose begin to move immediately. There are said to be twelve of rebels at Old Post, eight near Brownsville, and a gun on the railroad, mounted on platform car. I name these as particular objects of attention. There are also eight or ten regiments near Brownsville, and three batteries near Little Rock. It is also said that the Arkansas is high at Van Buren. I suppose you may be able to get Rear-Admiral Porter to co-operate by sending some boats up either White River or the Arkansas, or both. I will write him also. Understand me, I want to co-operate with Blunt, and perhaps with Davidson, but you are to move slowly and cautiously, in view of probable help, which is to return after the Mississippi is cleaned out. At the same time it is