nothing at eighter place. They were 2 miles beyond the railroad toward Warrenton; could see or hear nothing of any rebel forces, except convalescents on their way to Kelly's Ford. Two scouts returned to-night, and hour ago, from that direction. They report that they went 8 miles beyond Hartwood, on the Poplar road; thence crossed over to the Warrenton road. They saw several small parties of the enemy's cavalry-2,4,10, &c. It is said that there are four companies of the Ninth Virginia Cavalry, which were raised in that neighborhood, now scouring about that portion of the country. They break up into small parties, for the purpose of visiting their homes, gathering information, and catching our pickets. I have sent my best scout in that direction to-night, who will, probably, bring me accurate information to-morrow. I have two other parties out along the Rappahannock, toward Kelly's Ford, one of which is expected in every moment. As soon as it returns, I will send up a report. I shall be able to tell you if there is any force of the enemy between us and Warrenton Junction some time to-morrow.

Very respectfully, your obedient servant,

WM. W. AVERELL,

Brigadier-General of Volunteers, Commanding.

STAFFORD COURT-HOUSE, VA., December 19, 1862.

Major-General SIGEL,

Willard's:

General Stahel desires me to send you the following information: Hampton's rebel cavalry were at Brentsville to-day, where they had a skirmish with some of our cavalry-probably of Colonel Wyndham. Walker's division of rebel infantry is expected to reach Brentsville to-day, and Jackson's corps, and perhaps Longstreet's, is said to be moving up from Warrenton. A foraging party of the enemy were at Cedar Run, near Weaversville, to-day, with one regiment of infantry. The telegraph operator at Dumfries reports the wire cut to day in several places, so that we had no communication with Washington until this evening. Some Government teams are reported to be captured this side of Occoquan City, on the Telegraph road. All necessary steps have been taken to procure definite information, and all possible precaution used for the safety of the detachments. General Slocum has no information whatever of the skirmish at Brentsville, except what he heard from here. Nothing has been heard from Union Mills yet, nor from Wolf Run Shoals. General Steinwehr, in a letter of to-day, is of the opinion that the rebels are evacuating.

T. A. MEYSENBURG,

Assistant Adjutant-General.

NAVY-YARD,

Washington, December 20, 1862.

Major-General BURNSIDE:

Please give me early information when you can dispense with any or all of the gunboats in the Rappahannock. They should be removed before the ice makes.

A. A. HARWOOD,

Commander Potomac Flotilla.