FAIRFAX COURT-HOUSE, April 15, 1864.

Lieutenant Colonel J. H. TAYLOR:

I have the honor to report all quiet during the past twenty-four hours. The scouting party sent out under the command of Major Forbes returned at noon to-day, bringing with them 1 corporal and 5 privates prisoners, of Mosby's battalion. They belonged to the party which came down with Mosby last night and whose intention was undoubtedly to destroy bridges, from the fact that one of the party taken had a canteen of turpentine on his person.

A. H. GRIMSHAW,

Colonel, Commanding Division.

CULPEPER COURT-HOUSE, VA., April 15, 1864.

Major General F. SIGEL,

Commanding Department of West Virginia:

I send with this Lieutenant-Colonel Babcock, of my staff, to consult with you in person in reference to the preparations for the approaching campaign. I will state that the instructions which I communicated to you were based upon such information as is given by the maps, and as could be obtained by inquiries from those wh had previously been over the country.

The point to be attained was marked in my instructions; that is, in the spring campaign it is desirable to bring into the field all the troops possible.

From the extended line you have to guard no troops can be taken from you except to act directly from your line toward the enemy. In this way you must occupy the attention of a large force, and thereby hold them from re-enforcing elsewhere, or must inflict a blow upon the enemy's resources, which will materially aid us. This being the object, it is not necessary that the exact line marked out by me should be followed. It was selected with the view of keeping your present line covered. If this can be equally well done by starting from Gauley Bridge, I have no objections to that route.

The concentration preparatory to starting should go forward with all expedition, so that the two columns sent by you can be started by the 23rd instant, if called on to do so. I will give the signal from here for starting from Beverly or Gauley, as the case may be. It is now pretty certain that the enemy, suspecting a move up the Shenandoah Valley, have established a considerable force at Staunton to meet you. This may be, however, a cover for a formidable movement of the enemy by that route northward. This you will want to watch closely, and report any information you may obtain.

Confer freely with Colonel Babcock, and whilst he remains with you let us settle unalterably the line to be pursued by your forces. Of course I do not intend you to understand that Colonel Babcock will give your orders in this matter; but by a personal interview the best thing to do can be arrived at, and by telegraphing to me it can be adopted.

U. S. GRANT,

Lieutenant-General.