WAR DEPARTMENT,

Washington, D. C., August 27, 1862.

Major-General POPE,

via Falmouth:

The enemy is concentrating, it seems, between you and Alexandria, near Manassas and Bull Run. You must look out for this and immediately break it up, for your supplies must come from Washington, and you must fall back in this direction if compelled to retreat. Do not let him separate you from Alexandria. We will send out troops to meet you, but we are short of transportation. Keep me advised, if possible.

H. W. HALLECK,

General-in-Chief.

HDQRS. THIRD ARMY CORPS, ARMY OF VIRGINIA,
Warrenton, Va., August 27, 1862.

[Major-General POPE?]:

Your telegram of 12 midnight is only just received. I will endeavor to have Buford ascertain as soon as he can, and as far as he can, the extent of the enemy's movement toward White Plains. I saw General Sigel late last night and his scouts, and did not learn that the general had any other information than I gave you in my telegram of 10 o'clock p.m., and he was not aware of the negro's statement, which I sent you at 9 o'clock p.m. Your telegram of 11 p.m. last night was received. My corps is at present posted as follows: King's division on Sulphur Springs road, one brigade near Springs; Ricketts on Waterloo road, about 4 miles from town; Reynolds inside and between the others.

IRVIN McDOWELL,

Major-General.

WARRENTON, VA., August 27, 1862-8.45.

Major-General POPE:

I have just received your telegram of 5.30 a.m. I have ordered Sigel to send immediately a strong advance from his corps to seize the position of Buckland Mills or Broad Run, and follow immediately with his corps. Can you spare time to come to the instrument and have a conversation with me?

IRVIN McDOWELL,

Major-General.

HDQRS. THIRD ARMY CORPS, ARMY OF VIRGINIA, August 27, 1862.

Brigadier General J. B. RICKETTS,
Brigadier General RUFUS KING:

The major-general directs you to hold your division in readiness to move at a moment's notice toward Warrenton. Send in any wagons you may have at once, and put them in the train here on the road to Cattlett's, and report to Lieutenant-Colonel Myers.

Very respectfully, your obedient servant,

ED. SCHRIVER,

Colonel and Chief of Staff.