I sent to Lieutenant-Colonel Piatt the following dispatch:

" BALTIMORE, June 13, 1863 .

"Lieutenant Colonel DONN PIATT,

" Chief of Staff, Harper's Ferry:

"Instruct General Milroy to use great caution, risking nothing unnecessarily, and to be prepared for falling back in good order if over-matched . I rely on your having support afforded him, ass far as may practicable . In the meantime, go on with your concentration of of forces . Keep me advised of what is needed . What movement has been made from Romney?

"ROBT. C. SCHENCK,

" Major-General, Commanding .

" I sent also to General Milroy these two dispatches:

" BALTIMORE, June 13, 1863 .

" Major General R. H. Milroy, Winchester, Va.:

" It is some hours since I have heard from you. Is there any new movement or demonstration by the rebels?

"ROBT. C. SCHENCK,

" Major-General, Commanding .

"BALTIMORE, June 13, 1863 .

" Major General R. H. Milroy,

" Winchester, Va.:Of what rebel regiments were the prisoners you took yesterday? Can you hear of rebel infantry in the Valley?

" ROBT. C. SCHENCK,

"Major-General, Commanding .

" My reason for asking General Milroy to what regiments the prisoners he had taken belonged must be obvious. We knew that the rebel General Jones, something like a fortnight before, had left the Valley to join General Lee in front of Fredericksburg, or had gone in that direction, and also that all infantry of the First Maryland Line and other rebel infantry that were in the Valley had gone to Lee. We knew just what regiments of cavalry the enemy had been long keeping in the Shenandoah Valley, and which Milroy, with his force, had been accustomed to encounter and drive when they approached or threatened Winchester . General Milroy answered this telegram that evening at 9 o; clock, by courier to Martinsburg, but his answer was not received at headquarters until noon of the 14th.

" WINCHESTER, June 13, 1863-9 p. m.

"(Via Martinsburg, June 14-11 a. m.

"Major-General SCHENCK:

"Have been skirmishing ; occasionally pretty severe . One battle, in which the enemy were repulsed and his lines broken and scattered by two of the Ohio and one Virginia Regiment, assisted by the artillery . We captured some prisoners of a Louisiana brigade, who say they belong to Ewell's, recently Jackson's old corps, and that this corps is all in front us; also Jenkins and Imboden. McReynolds will soon be here . He had a fight with the rebels, and repulsed them before leaving Berryville . He is closely pursued and hard pressed by a heavy body of cavalry. I can hold this place five days if you can relieve me in that time. They will surround, but can't take, my fortifications .

" R. H. MILROY,

"Major-General .

" That evening, I also received this telegram from General Kelley:

" HARPER'S FERRY, June 13, 1863.

" My scouts to Loudoun County returned. Went as far as Hillsborough ; saw no enemy . The rebel citizens in that neighborhood report that General Lee is on his way to drive General Milroy out of Winchester .

"B. F. KELLEY, "Brigadier-General . "