HEADQUARTERS EXPEDITIONARY CORPS,
Port Royal, S. C., February 15, 1862.

The ADJUTANT-GENERAL U. S. ARMY,

Washington, D. C.:

SIR: As I informed you on the 8th instant, General Viele had orders to erect his battery on the Savannah River, whether the Navy could assist him or not. Accordingly a battery of six siege guns was erected at Vennus Point, on Jones Island, on the night of the 11th instant, and fortunately without molestation from the enemy.

In order to render the blockade of the river complete, a similar battery is to be erected at the head of Long Island. The preparations for this have, line the other, been ready ever since the day the reconnaissance, the 28th of January.

As the naval gunboats cannot be prevailed upon to enter the river, I have given General Viele orders to likewise erect this without them, which I think will be done without much hazard, now that the Venus Point battery is up.

Comodore DuPont will leave two or three light-draught gunboats in Mud River, which will probably tend to cover our batteries from gunboats of the enemy coming down the Savannah and attempting to take us in rear by way of Mud River.

I have sent a 10-inch columbiad down three, which will now be necessary without the aid of the gunboats.

General Wright's troops are yet in Warsaw Sound, waiting for the Navy.

Our delays since the middle of January have grieved me to almost a state of mortification. The season in rapidly passing; we can work six weeks longer, and probably twelve. Now, if anything serious is to be done in that time over and beyond the expedition that is about to start, I will state candidly and explicitly what will be required at once: all the means of transportation that have been asked for (which I believe have been ordered but which have never got here); the mortars and siege equipage (which are gradually arriving, though none of the 13-inch are here yet), and 10,000 infantry troops.

The great extent of coast we have had to garrison and guard has absorbed a good portion of our troops.

The mortar battery against Pulaski will go up as soon as the mortars arrive.

Savannah is out of the question with our force, particularly after the detachments to Fernandina and Endisto Island, which I did not desire to make at present; but, in order to do soothing in the absence of our ability to get on the main for want of transportation, was compelled to do so.

Very respectfully, your obedient servant,

T. W. SHERMAN,

Brigadier-General, Commanding.

[Indorsement.]

The 10,000 infantry asked for are not at present available. Recommend to General Sherman to reduce Fort Pulaski in preference to attempting Savannah.

GEO. B. McCLELLAN,

Major-General.