WINCHESTER, VA., August 29, 1862.

Major-General HALLECK, General-in-Chief:

On the 27th I started 6 of my men across the Blue Ridge, through Ashby's Gap. Has them armed with shot-guns, and chased them into the enemy's line with a cavalry force from here. they have just returned, and furnish the following, which may not be new, but which I fully rely on:

Jackson is at Manassas Junction with 50,000 men. Longstreet was near Salem yesterday (28th). White's cavalry at Middleburg. they were to execute Corbin yesterday, one of Captain Means' men, captured at Waterford, who they claimed as a deserter. Between Bloomfield and Middleburg my men met a messenger going to Bloomfield to meet and old man from Harper's Ferry, who carries news of the movements of Federal troops in that vicinity. Did not get his name. He ought to be found. General Pope is considered by the rebels as surrounded. No change of escape, except via Aquia Creek.

JULIUS WHITE,

Brigadier-General, Commanding.

P. S. - Cullum left here on his return this morning at 7 o'clock.

NAVY DEPARTMENT, August 29, 1862.

SENIOR NAVAL OFFICER, off Aquia Creek:

Retain all the vessels sent from James River at Aquia Creek until further orders, but act in conjunction with General Burnside, to whom you will communicate at Falmouth, Va.

GIDEON WELLES,

Secretary of the Navy.

NAVY DEPARTMENT, August 29, [1862.]

Major General AMBROSE E. BURNSIDE,

U. S. Army, Falmouth, Va.:

I have sent an order to Aquia Creek to detain the boats. Wilkes is ordered up to the Potomac with a dozen vessels and will assume command.

G. V. FOX,

Assistant Secretary of the Navy.

FORT MONROE, August 29 [1862.]

Honorable SECRETARY OF THE NAVY:

SIR: I received your dispatch at Newport News about sunset, where I arrived with the Wachusett and Dacotah, and the rest of the fleet close at hand. I shall make all haste in transferring the vessels of the squadron not designated in your dispatch over to Rear-Admiral goldsborough, and proceed at once to the Potomac and Washington, agreeably to your instructions. I would state that for active operations in the Potomac I would like to bring with me the Jacob Bell and Yankee and the tug Alert. The rear-admiral has four tugs here, and the Dragon, which is under repairs at this place. You may be assured