CAVALRY CORPS, Linden, Va., July 23, 1863-8 a. m.

General GREGG:

The major-general commanding directs me to request you to keep a close lookout toward Warrenton, and give all the information of the enemy you can gather. General Custer has gone to Amissville. Very respectfully, your obedient servant,

C. ROSS SMITH,

Lieutenant-Colonel, and Acting Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC, Markham Station, July 23, 1863-10. 30 a. m.

Major-General Sedgwick,
Commanding Sixth Corps, Rectortown:

The major-general commanding directs that you move immediately the two division of your corps now at Rectortown, to Barbee's Cross-Roads, and take position there, to watch the enemy from the direction of Chester Gap. You will take with you your ambulances and ammunition train. The other trains of your corps will be sent to White Plains.

A. A. HUMPHREYS,

Major-General, Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC, Near Markham Station, July 23, 1863-11. 20 a. m.

Commanding Officer Twelfth Corps:

The major-general commanding directs that you move immediately to Markham Station, on the Manassas Gap Railroad, leaving Ashby's Gap to be watched and guarded by the cavalry. You will not debouch upon the road leading up to Manassas Gap, but leave it clear, holding your command ready to move at very short notice, with your ambulances and ammunition train. Should the enemy be already moving to attack Ashby's Gap in force when this dispatch reaches you, you will no, of course, abandon the Gap unless forced by the enemy to do so, moving in that event in the direction just indicated. Very respectfully, &c.,
A. A. HUMPHREYS,

Major-General, and Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC, Linden, July 23, 1863-2. 45 p. m.

Commanding Officer Third Corps:

Your dispatch is received. General Sykes is in your rear with the Fifth Corps. General Hays, with the Second Corps, will be posted on the road from this place to Sandy Hook (Chester Gap), 5 miles