HEADQUARTERS ARMY OF THE POTOMAC, July 13, 1863.

General PLEASONTON,
Cavalry Headquarters:

Orders have been sent to retain the First Brigade Horse Artillery (Robertson's), and let them refit where they are.

HENRY J. HUNT,

Chief of Artillery.

JULY 13, 1863-9. 30 p. m.

Colonel E. SCHRIVER,

Commanding at Frederick:

The commanding general directs that Colonel Gibbs' regiment, One hundred and thirtieth New York Volunteers, join the Fifth Corps, which is in the vicinity of Jones' Cross-Roads, on the Boonsborough and Williamsport pike.

S. WILLIAMS,

Assistant Adjutant-General.

HEADQUARTERS ARMY OF THE POTOMAC, July 13, 1863.

General M. C. MEIGS,
Quartermaster-General, Washington, D. C.:

General Smith arrived last night at Cashtown with some 7, 000 new troops, They come without supplies, or means of transporting them. It seems incredible that these troops of Generals Couch and Smith should be in such a destitute condition, having had so long a time for preparation in a country of ample resources. Our department at Harrisburg must have acted on a small scale. These troops have, however, but a few days to serve, and were not too happy to march here. They will be distributed among our old corps for the expected battle. Should further operations call for fitting out commands within reach of this army, I will be responsible for its being well done, if you will intrust the duties to my direction. I have suitable officers who will execute your orders and mine.

RUFUS INGALLS,

Brigadier-General, and Chief Quartermaster.

CHAMBERSBURG, PA., July 13, 1863-9 a. m.

Major-General HUMPHREYS,

Chief of Staff, Army of the Potomac:

The part of General Milroy's troops serving with me, infantry and cavalry, were last evening ordered to join the Army of the Potomac, via Greencastle. I trust they will be with you to-morrow. Dana's division, 12, 000 strong, including fourteen Napoleons, Pennsylvania militia, I hope will get to Greencastle to-morrow night. If it is your wish for them to march into Hagerstown, I think they can be supplied from this point. My transportation is increasing. The roads south of this point are not in condition to haul any great amount of supplies.

D. N. COUCH,

Major-General.