HEADQUARTERS ARMY OF THE POTOMAC,
September 22, 1862 - 4 p. m.

Major-General BURNSIDE:

GENERAL: The commanding general directs you to hold your whole corps in readiness to move to Harper's Ferry to-morrow. He also directs you to send that portion of the Fifth Cavalry (regular) now with you to join its regiment.

General Pleasonton is directed to furnish you sufficient cavalry (if you have not already enough) to watch the fords in your vicinity. Please report the number and strength of cavalry regiments now with you. The general further directs you to send the boat howitzers at day-light to-morrow morning to Harper's Ferry, to be placed on Loudoun Heights.

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

R. B. MARCY,

Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC,
September 22, 1862.

General FITZ JOHN PORTER,

Commanding Fifth Corps:

GENERAL: In reply to your note of this morning, you are authorized to send a flag of truce to the opposite side of the river, to recover the bodies of our dead. The general commanding suggests that it will be well, if there is no appearance of force opposite you, that you send over some cavalry scouts to determine the fact after the flag of truce is disposed of and the bodies recovered.

I am, very respectfully,

R. B. MARCY,

Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC,
September 22, 1862 - 2 p. m.

General FITZ JOHN PORTER:

GENERAL: The commanding general directs that you stoop the flag of truce and continue your reconnaissance, only exercising due caution about not being drawn into any ambuscade. You can assure the rebel officer (as you propose) that their wounded are properly attended to, which obviates the necessity of the surgeon coming over; and that Shepherdstown will not be fired into without some absolute necessity. If you can drive the enemy's cavalry from Shepherdstown we may be able to take a large number of their wounded.

Very respectfully,

R. B. MARCY,

Chief of Staff.

HEADQUARTERS DEFENSES OF WASHINGTON,
September 22, 1862 - 3.10 p. m.

Major General GEORGE B. MCCLELLAN:

A strong cavalry reconnaissance toward Aldie and Ashby's Gaps is expected to return to-day, or early to-morrow morning. I ordered Stahel's division, of Sigel's corps, to advance to Centreville last night and early