On the 25th, the brigade rejoined the division and marched to Orleans.

Very respectfully, your obedient servant,

W. MERRITT,

Brigadier General of Volunteers, Comndg. Reserve Brigade.

Captain M. W. KREOGH, A. D. C., and A. A. A. G., First Div., Cavalry Corps.

No. 341. Report of Captain Julius W. Mason, Fight U. S. CALVARY,

HEADQUATERS FIFHT U. S. CALVARY

June 23, 1863.

SIR: In compliance with circular, I have the honor to report that the Fifth U. S. Cavalry Regiments moved with the brigade from camp, near Middleburg, Va., on the morning of June 21. During the first hours of the march, the regiment was in advance of the brigade, but having moved on a road that was not the proper route or it being deemed expedient to go in another direction, the regiment countermarched, and, retracing its route, struck the column, of the balance of the brigade moving on another road. I here received an order from the major commanding not to follow him in advance of the brigade, but take place in rear of the First U. S. Cavalry. This brought my regiment nearly in rear of the brigade. In this order the regiment moved forward in column of fours until it arrived at Upperville, at about 4. 30 p. m. Here the regiment was formed in close column of squadrons, and moved forward at a brisk trot. At this point the Sixth and First U. S. Cavalry, with the exception of one squadron, which was immediately in my front, charged. I here lost 1 man killed by a bullet. I then broke my column, by fours, to enable me to get through a stone fence bordering the road, and, on entering the road, met General Pleasonton, who ordered me to form in front of a skirt of woods on the left of the road. I did so promptly at the gallop, and moved forward at the trot, to participate in the fighting then going on. I had moved but a short distance when I received a peremptory order from General Pleasonton, through an aide, to halt my command until I received orders from him to move. I remained halted until Captain Merritt, of the Second U. S. Cavalry, coming up, informed me that he had orders from General Pleasonton to move forward with his regiment and the Fight. I accordingly moved at a trot, and my movements were afterward directed by the acting assistant-adjutant-general of the brigade, the Second U. S. Cavalry moving to the left and the Fight moving to the front, when, being in close column of squadrons, the regiment, together with the Sixth U. S. Cavalry, were dismounted, and thrown forward as skirmishers. After being dismounted about an hour, and having compelled the enemy to retire, the regiment was recalled and mounted, and again took the advance of the brigade, moving forward in column of squadrons in the direction of Ashby's Gap. Advanced to the outside line of skirmishers of Colonel Gregg; then moved to the rear and