HEADQUARTERS SECOND CAVALRY DIVISION,
Hagerstown, Md., July 27, 1864.

Captain P. G. BIER,

Assistant Adjutant-General:

CAPTAIN: I have the honor to acknowledge the receipt of your dispatch of this date respecting ammunition. In reply I beg leave to state that all the mounted men of my division are on duty, except the reserve at this point necessary to secure the safety fo the stores. There are at and about Harper's Ferry a large number of detachments from the division, including men from every regiment. I request that these men be sent up with the ordnance train. They will add greatly to my effective force, and materially decrease the labors of my men, who are already much fatigued.

Respectfully, your obedient servant,

WM. W. AVERELL,

Brigadier-General.

HEADQUARTERS SECOND CAVALRY DIVISION,
Hagerstown, Md., July 27, 1864.

Captain P. G. BIER,

Assistant Adjutant-General:

CAPTAIN: I send a summary of the information received up to this evening of the movements of the enemy in the Shenandoah Valley. Last evening a cavalry force of the enemy appeared before my pickets at Williamsport and made a demonstration of crossing, but were held in check, and to-day retired toward Martinsburg. This morning they were reported trying to cross at Back Creek, Four Locks, and Cherry Run. A brigade of cavalry sent up to those places reported that they had destroyed Back Creek bridge; that 30 had crossed at Back Creek and about 400 or 500 infantry crossed at Little Georgetown in boats, but on the approach of our forces they recrossed. Word has been sent me from Martinsburg that Early, Breckinridge, and Ransom were in the town this morning with 20,000 men. It was reported in the rebel camp that a column had gone toward Cumberland. Colonel Thoburn, commanding First Division, has just come in from Cherry Run, having come by Back Creek. He reports that the force that burned Back Creek bride has retired toward Hedgesville. He also reports having heard artillery firing in the rear of Winchester yesterday. He was told by citizens living on his road returning that the firing had been very heavy. All is quiet to-night along the river.

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

WM. W. AVERELL,

Brigadier-General.

HEADQUARTERS SECOND CAVALRY DIVISION,
Hagerstown, Md., July 27, 1864.

Colonel A. S. MOORE,

Commanding First Brigade:

COLONEL: The general commanding directs me to say that your command will be required to watch the Potomac from Hancock to Dam Numbers 5. He wishes the fords and crossing places in the vicinity of