arrived and is now debarking. Several schooners with cavalry arrived this morning; also Pleasonton.

R. B. MARCY,

Chief of Staff.

HEADQUARTERS ARMY OF THE POTOMAC,
Camp near Alexandria, September 1, 1862.,

Brigadier General JACOB D. COX,

Commanding Division, Upton's Hill:

SIR: The general commanding directs that, if you have force enough for the purpose you immediately send a pretty strong scouting party of cavalry to Vienna, to return and leave small parties at the intersection of all the roads leading from the Vienna road toward our works. These parties should be left in going out.

Please report whether you have enough cavalry to undertake this duty.

Very respectfully, your obedient servant,

S. WILLIAMS,

Assistant Adjutant-General.

UPTON'S HILL, VA., September 1, 1862.

S. WILLIAMS, Brigadier-General and A. A. G.:

Your dispatch in regard to scouting Vienna road received. I have two troops now on it, expected in this evening. I sent 100 out immediately to carry out the directions you gave. They will meet the first on the way.

J. D. COX,

Brigadier-General.

UPTON'S HILL, September 1, 1862-8.30 p.m.

General S. WILLIAMS:

The cavalry at Vienna to-day just returned. All quiet there at dark. No rebel force been in the vicinity for three days. They received a report, from persons thought reliable, that Fitzhugh Lee's and Robertson's (late Ashby's) cavalry went through Frying Pan toward Dranesville this morning. This is confirmed in part by a paroled prisoner, who left Ox Road Junction early this morning, who says he saw a regiment of cavalry start on that road, and that more force of the same kind was ready to start apparently in same direction.

J. D. COX,

Brigadier-General.

UPTON'S HILL, VA., September 1, 1862.

Major-General McCLELLAN:

Have just received following report, dated 9.30 p.m., from our outposts at Holmes' Run, on the Columbia pike. Report is:

My information just received is that the enemy have driven back our center and right wing, outflanking us, and at dark were shelling Centreville. All the trains have been ordered to Alexandria.

J. D. COX,

Brigadier-General.