The major-general commanding requests that General Kilpatrick will report which roads his cavalry must are in passing out and in; they must be reduced to the smallest number practicable. He will also report the cases of stopping his messengers,&c., that occurred to-day.

A. A. HUMPHREYS,

Major-General and Chief of Staff.

BEALETON, VA., January 31, 1864-5. 10 p. m.

Colonel TAYLOR:

I received information through a negro, who came to my lines for that purpose, the enemy contemplate a raid on the railroad between Warrenton Junction and Catlett's, some time between now and Tuesday night. Their force is under Captain Steel, and about 125 strong.

I am, your obedient servant,

H. H. WILSON,

Captain Company F, Sixteenth Pennsylvania Cavalry.

CUMBERLAND, MD., January 31, 1864-5 a. m.

(Received 2. 15 p. m.)

Brigadier General G. W. CULLUM,

Chief of Staff:

Colonel Mulligan reports that a wagon train going to Colonel Thoburn, at Petersburg, guarded by 800 men,was attacked near Williamsport, at 3 p. m. yesterday, by Rosser's brigade and Gilmor's command, and, after a severe fight of four hours, our forces were repulsed and the wagon train captured. Colonel Snider, of the Fourth Virginia Cavalry, who was in command of the escort, reports his loss in killed and wounded at about 80, and he thinks the enemy's loss much greater. Colonel Mulligan has moved out from new Creek to relieve Thoburn. The enemy's force was estimated at 2,000 all mounted, with four guns, and it is believed he has more force behind. I have ordered Sullivan to send a cavalry force at once, via Winchester and Wardensville, toward Moorefield, to recapture the train if possible, and assist in relieving Thoburn. This may be a part of a plan to assail my whole line from here to Harper's Ferry by General Early. If so, may I suggest that a movement of a force from General Meade's right to Luray or Port Republic would be of great importance? I have deemed it of the utmost importance to hold Petersburg heretofore, in order to prevent the enemy from occupying the South Branch Valley and drawing from it supplies, which are abundant, as well as to prevent him from enforcing the conscription laws; but I fear I shall be compelled to withdraw my force, as this is the second wagon train we have lost. This one, unfortunately, was loaded with commissary stores.

B. F. KELLEY,

Brigadier-General.