HEADQUARTERS ARMY OF VIRGINIA,
Warrenton Junction, August 27, 1862-4 a.m.

Major General FITZ JOHN PORTER,

Commanding Fifth Army Corps:

GENERAL: Your note of 11 p.m. yesterday is received. Major-General Pope directs me to say that, under the circumstances stated by you in relation to your command, he desires you to march direct to this place as rapidly as possible. The troops behind you at Barnett's Ford will be directed by you to march at once direct to this place or Weaversville, without going to Rappahannock Station. Forage is hard to get, and you must graze your animals as far as you can do so. The enemy's cavalry have intercepted our railway communication near Manassas, and he seems to be advancing with a heavy force along the Manassas Gap Railroad. We will probably move to attack him to-morrow in the neighborhood of Gainesville, which may bring our line farther back toward Washington. Of this I will endeavor to notify you in time. You should get here as early in the day to-morrow as possible, in order to render assistance should it be needed.

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

GEO. D. RUGGLES,

Colonel and Chief of Staff.

WARRENTON JUNCTION,

Via Falmouth, Va., August 27, 1862-10 a.m.

Major-General HALLECK:

The enemy has massed his whole force at White Plains, with his trains behind him. A strong column penetrated by way of Manassas Railroad last night to Manassas, drove off a regiment of cavalry and one of infantry, and I fear destroyed several bridges. My position at Warrenton is no longer tenable. I am now moving my whole force to occupy the line from Gainesville to railroad crossing of Cedar Creek, on Alexandria and Central [Orange and Alexandria] Railroad. Neither Heinzelman nor Porter has any transportation and but little ammunition; cannot move off the railroad. All forces now sent forward should be sent to my right at Gainesville. Whether the enemy means to attack us or not I consider doubtful; he never crossed Rappahannock River, but masked every ford with heavy batteries, under cover of which he kept moving to my right close along the river. I never had the opportunity to attack him without forcing the passage of the river in face of very superior forces. I think it possible he may attempt to keep us in check and throw considerable force across the Potomac in direction of Leesburg. Under all the circumstances I have thought it best to interpose in front of Manassas Junction, where your orders will reach me. Neither Sturgis' nor Cox's commands have come up. Heitzelman's has no artillery. I am pushing a strong column to Manassas Junction to open the road. I do not know yet what damage has been done. You had best send a considerable force to Manassas Junction at once and forage and provisions, also construction corps, that I may repair the bridge and get the railroad trains to the rear. I send this by way of Barnett's Ford, but will endeavor to communicate with you from Manassas to-night.

JNO. POPE,

Major-General, Commanding.