WAR DEPARTMENT, October 16, 1863-2. 50 p. m.

JOHN W. GARRETT, Esq.,

Baltimore:

One division of Longstreet's corps went to Charleston, while the rest went to Chattanooga. It is believed that the Charleston division have been sent back to Lee, so that the report of teh two brigades of Longstreet being at Strasburg, and moving across in rear to Back Creek, really may be true. The utmost vigilance should be observed, and no pains spared to ascertain the direction of the movement from Strasburg.

EDWIN M. STANTON.

MARTINSBURG, VA., October 16, 1863. (Received War Department 7. 45 p. m.)

Colonel SHARPE,

Headquarters Army of the Potomac:

The prisoners are from Gilmore's cavalry battalion, not in any brigade. They left Newtown, Va., 40 in number, on Wednesday, 14th instant, at 4 p. m., for the purpose of tapping the Baltimore and Ohio Railroad at Back Creek. We captured 23 of them 9 miles west of this point, on Back Creek road, near Hedgesville, yesterday. Two of teh prisoners say they saw several footmen, regularly armed, near Strasburg, who said they were stragglers from a command of infantry marching in teh direction of North Mountain, and had come from Front Royal. One prisoner says the stragglers belonged to Johnson's division, Longstreet's corps, but does not know what regiment or brigade. I do not place so much reliance in their stories now as I did last night. Will send you a copy of a letter found on one of the prisoners, which letter foreshadows intended movement of the rebel army in Virginia. No account of the old man. Will report again as soon as scouts are in.

MICHAEL GRAHAM.

NEW YORK, October 16, 1863. (Received 2. 30 p. m.)

Major General H. W. HALLECK,

General-in-Chief:

Your telegram of teh 15th is just received. The infantry at Camp Sprague (1,700) will be ready this evening. They are being armed this morning. As it involves no delay the cavalry will be sent direct. I had already arranged with the adjutant-general of the State to notify me telegraph, so that I may have transportation in readiness for the troops from the interior at the moment of their arrival here.

ED. R. S. CANBY,

Brigadier-General.

HDQRS. ARMY OF THE POTOMAC, October 17, 1863. (Received 10 p. m.)

Major-General HALLECK:

Reports from scouts and teh cavalry would indicate a movement of teh enemy into the Loudoun and, probably, the Shenandoah Val-