HDQRS. CAVALRY CORPS, ARMY OF THE POTOMAC,
September 16, 1863-1. 30 a. m.

Brigadier-General GREGG,

Commanding Second Cavalry Division:

GENERAL: The major-general commanding directs that you hold Cedar Mountain as long as possible, and General Warren will support you at Fox Mountain. The Second Corps will occupy from Culpeper Court-House to Fox Mountain. You had better fall back toward Fox Mountain, if you are forced. The Army of the Potomac crosses and takes up position on this side of the Rappahannock this morning. You can have your pickets withdrawn from Carter's Run.

C. ROSS SMITH,

Lieutenant-Colonel, and Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC,
September 16, 1863.

Commanding Officer Third Corps:

Information just received leads to the supposition that the enemy is crossing the Rapidan with his infantry. The commanding general therefore directs that you move up as rapidly as practicable to take the position assigned you in the instructions of last night, communicating with General Sedgwick on your right and General Warren on your left.

Very respectfully, &c.,

S. WILLIAMS,

Assistant Adjutant-General.

HEADQUARTERS ARMY OF THE POTOMAC,
September 16, 1863.

Commanding Officer Sixth Corps:

Information just received leads to the supposition that the enemy is crossing the Rapidan with his infantry. The commanding general therefore directs that you move up as rapidly as possible with your command to take the position indicated in your instructions of last night communicating with General French on your left.

Very respectfully, &c.,

S. WILLIAMS,

Assistant Adjutant-General.

HEADQUARTERS ARMY OF THE POTOMAC,
September 16, 1863.

Commanding Officer Twelfth Corps:

I am instructed by the commanding general to say that you have been ordered with your command down to Raccoon Ford, to relieve the cavalry pickets and to closely watch the movements of the enemy. Although it is not expected that, in case the enemy should attempt to cross the river in your front in greatly superior force, you will be able to prevent the accomplishment of their object, yet the commanding general looks to you to oppose and retard any movement they may make in this direction sufficiently to enable the commanding general to be informed of such movement, and to make