they say Duffie gave the order for his men to scatter and get back

the best way they could. Buford's people brought in some 20 of

them yesterday, and, as my troops are on both sides of the mountains in strong force, we ought to get them all back.

I cannot understand Duffie's conduct, and must await further advices. Can the Eighth Pennsylvania Cavalry be spared?

I shall report again as soon as I hear from the troops engaged.

Very respectfully,

A. PLEASONTON,

Brigadier-General, Commanding.

Major-General BUTTERFIELD,

Chief of Staff.

P. S. - I send you a box of cartridges of rebel manufacture. They are better put up than ours.

HEADQUARTERS CAVALRY CORPS,
Aldie, June 19, 1863 - 3 p. m.

GENERAL: I have the honor to report for the information of the commanding general that General Gregg, with two brigades of his own and one of General Buford's division, advanced on the Middleburg road this morning, and has, up to this time, driven the enemy steadily before him in the direction of Upperville, with sharp fighting and considerable loss to the enemy. He has sent in about 50 prisoners so far, one lieutenant-colonel and a number of officers of less rank, all from North Carolina, who say that the brigade in front of Gregg is [B. H.] Robertson's, composed of North

Carolina troops, supported by two other brigades, all under command of General Stuart.

From similar sources, I learn that Fitz. Lee's brigade, which I engaged here day before yesterday, went on that night to Warrenton.

Colonel Devin, who went through Thoroughfare Gap with his brigade, reports that-

Colonel De Forest went to within 3 miles of Warrenton yesterday. I did not see him, but his men report that they learned that there were 2, 000 cavalry [enemy's] there. De Forest returned to Fairfax Court-House last night.

The return of Colonel De Forest exposes my left flank, as I understood that General Stahel was to have a force at Warrenton, and in consequence advanced my left farther than I should otherwise have done.

I inclose a pass taken from an infantry soldier of Longstreet's command, just captured, who states that [R. B.] Garnett's brigade was between Amisssville and Little Washington yesterday, and the fact of his being required to return by 10 to-day shows those troops are moving this way.

A copy of the dispatch of the 17th [the original of which was taken on Major Stirling], has just been received by Lieutenant Spangler.

Very respectfully, your obedient servant.

A. PLEASONTON.

Brigadier-General, Commanding.

Brig. General S. WILLIAMS,

Assistant Adjutant-General, Army of the Potomac.