Hines, my aide-de-camp, was on a hill in view of part of their camp the entire day yesterday. He saw forty to sixty large tents, capable of accommodating twenty-five men each, and saw the ends of rows of tents extending back, and which to him appeared as a large camp. The enemy were in motion several times during yesterday, and their columns were seen marching in our direction. We are sure they were last night in the rear of a round hill in front of Belington, and within three-fourths of a mile, and in numbers at least two or three thousand. Scouts on the hill this morning report their tents in the same position as yesterday.

The instructions of the commanding general will be carried out, although it is difficult to restrain our men from advancing. I hardly know in what terms to convey to you their enthusiasm. Their coolness under such fire as we have been subjected to (incessant since our arrival) is very creditable to them, and established beyond all question, if proof were needed, that they can be relied upon in any emergency.

The regiments in advance are Milroy's Ninth Indiana, Barnett's artillery, Steedman's Fourteenth Ohio, and Dumont's Seventh Indiana, which regiments deserve special mention.

Rumors from several sources reached us yesterday of re-enforcements to the enemy from the direction of Beverly, but they are not of a character to be reported to the commanding general under the instructions I have received.

Owing to the rapid march from Philippi, made necessary by the instructions of the commanding general of July -, it was impossible to bring much baggage or provisions. Our men are very short of the latter, and we have only seven wagons to the regiment and such scanty assistance as we hire to keep us supplied.

I am, sir, very respectfully, your obedient servant,

T. A. MORRIS,

Brigadier-General.

Major S. WILLIAMS, Assistant Adjutant-General.

P. S. - Information just in reports the enemy as having retired from the wood in front of belington. Reconnoitering parties are out in several directions, and the movements of the enemy will be closely watched.

JULY 13, 1861.

SIR: After resting two hours near Leadsville our advanced column, Steedman, Dumont, and Milroy, moved on this morning at 3 o'clock in pursuit of the enemy. I am now advancing, at 5 o'clock, with the balance of my force to support them. We left Belington in pursuit yesterday with four wagons of hard bread and pork, which were all the available wagons, the balance having been sent to Philippi to bring up supplies from there. As I have before reported, we have but seven wagons to the regiment. Our men have necessarily been restricted in their rations, and must be more so as we advance. I shall pursue just as long as it is possible with the means of transportation at my command. If you could send us provisions, it would greatly assist us in the advance.

Inclosed I send you a dispatch, this moment received from Captain Benham, who is with the advance.

I am, very respectfully, your obedient servant,

T. A. MORRIS,

Brigadier-General.

Major S. WILLIAMS, Assistant Adjutant-General.