[SEPTEMBER 17, 1862.]

General PORTER:

Our batteries on the left have been firing with heavy guns on the enemy's left wing, which has lately advanced some. Our light batteries on the left are covering our column, which is crossing the stone bridge. We are advancing the Ninth Corps on Sharpsburg. Captain Benjamin is firing, by order of General Burnside, and has silenced a battery of the enemy.

J. D. COX,

Brigadier-General, Commanding Ninth Corps.

HEADQUARTERS ARMY OF THE POTOMAC,
September 17, 1862 - 1.25 p. m.

Brigadier-General MEADE:

GENERAL: The commanding general directs that you temporarily assume command of Hooker's corps, and use every effort in your power to reorganize it and make it serviceable. It is absolutely necessary that the right should be held, and the troops must be got together and into position for that purpose as rapidly as possible.

Yours, very respectfully,

A. V. COLBURN,

Assistant Adjutant-General.

HEADQUARTERS ARMY OF THE POTOMAC,
September 17, 1862 - 3.10 [p. m.]

General MEADE:

GENERAL: The commanding general directs that you at once take command of the army corps which was under the command of General Hooker this morning. This order is given without regard to rank, and all officers of the corps will obey your orders. The commanding general also directs me to say that you will be held responsible for this command as herein assigned to you.

Very respectfully,

R. B. MARCY,

Chief of Staff.

HEADQUARTERS SYKES' DIVISION,
September 17, 1862 - 7 a. m.

General PORTER:

GENERAL: My skirmishers are across the bridge - three companies. They have had some firing this morning. The enemy's guns are where they were yesterday, and are firing at the hill where Benjamin's guns were yesterday. A large force of infantry (enemy's) are to the left of Sharpsburg, up the valley, awaiting evidently the approach of our attack from that direction. They have set fire to farm houses, &c.

Very, respectfully,

GEO. SYKES,

Brigadier-General.