HEADQUARTERS FIFTH ARMY CORPS, October 18, 1863.

[Major General A. A. HUMPHREYS,
Chief of Staff, Army of the Potomac:]

GENERAL: Am I to move the balance of teh Fifth Corps toward Centerville at once, or await further orders? The last order says, "Hold it ready to move at daylight. " It has been held ready, but no further instructions have been received. The order of 11. 20 p. m. did not reach me until 3 a. m. of the 18th. That of 1 a. m. came first. This will explain why I sent to you in reference to Griffin's movement.

Respectfully,

GEO. SYKES,

Major-General.

MANASSAS JUNCTION, October 18, 1863.

Captain SUYDAM,

Assistant Adjutant-General:

CAPTAIN: Since driving in the enemy's pickets last night everything has remained quiet. Our pickets have been thrown forward within 1 1\2 miles of Bristoe. I shall remain where i am until further instructions from you.

General Warren can give me no support in case of attack, and I think the enemy are moving around in the direction of Chantilly, and, perhaps, retreating.

I send you back, in charge of a courier, a deserter, from whom I think you can get important information.

I am entirely out of forage and rations, and if you wish me to remain here longer, please have me supplies at once.

Respectfully,

ALFRED GIBBS,

Colonel, Commanding Cavalry Reserve Brigade.

HEADQUARTERS ARMY OF THE POTOMAC, October 18, 1863-8. 15 a. m.

Commanding Officer Fifth Corps:

The major-general commanding directs that you move with the remainder of your corps to Fairfax Court-House, and send out a division on the old ox road to the vicinity of Hawxhurst's Saw-Mill, or some point intermediate between the two that will afford a good position. General Sedgwick informs me that the enemy seems to be establishing a line of infantry pickets opposite to his, which is taken as an indication that he intends to advance from that direction.

Very respectfully, &c.,
A. A. HUMPHREYS,

Major-General, and Chief of Staff.