TAZEWELL, December 20, 1863.

GENERAL: A citizen came into Evans' Ford this morning and reported to the officer in command there that a brigade of rebel cavalry were crossing the Clinch, 8 miles above Evans' Ford, and were moving in this direction. I have halted the regiments that were starting from here until the truth can be ascertained.

O. B. WILLCOX,

Brigadier-General.

Major-General FOSTER.

TAZEWELL, December 20, 1863. (Received 21st.)

GENERAL: Major Conover scouted from Mulberry Gap up Sneedville road, and across the Clinch to Sneedville, within 6 miles from Flat Gap. Except a few guerrillas in the mountains, he has driven out what rebels there were this side of Clinch River. He reports that the rebels are throwing up works in Flat Gap and Union Gap, and posted artillery.

Now would be a grand opportunity for a descent on the salt-works from Berlin. If we had the cavalry it would be a good thing also to burn the New River railroad bridge. I have authorized Major Conover to promise $ 5,000 to Union men tho might do the work. I am waiting orders with regard to the Twenty-third Corps.

O. B. WILLCOX,

Brigadier-General.

Major-General FOSTER.

NEAR WALKER'S FORD, December 21, 1863.

GENERAL: I arrived here last evening with the available force of my command. Part was detained above till this soon by reports of the enemy's crossing Clinch River, the truth of which is not known yet. After leaving a sufficient force at Tazewell, of course I am far from strong. Wagons are out for subsistence, and I expect them in this evening. I have started an ammunition train to Knoxville, 18 wagons loaded with Enfield rifle ammunition, caliber.58, which I made up on seeing your dispatch to General Grant. Your dispatches with regard to the Twenty-third Corps, dated 17th and 19th instant, were received yesterday. Please relieve me as soon as possible from the unpleasant state of suspense in which I have been placed for nearly three months about my command. I have been without a positive command, and tied to six-months' troops and recruits, while my juniors have been commanding corps. If this continues I must resign or cease to be a man. You will appreciate my feeling, and I have every confidence in your justice.

I remain, general, very respectfully, your obedient servant,

O. B. WILLCOX,

Brigadier-General.

Major-General FOSTER.

26 R R-VOL XXXI, PT I