Water is already beginning to be scarce, and our well-digging has not been successful.

I am, general, respectfully, your obedient servant,

JNO. POPE,

Major-General.

BUELL'S HEADQUARTERS, June 10, 1862.

General HALLECK:

The following from General Morgan from Lambdin's, foot of Cumberland Mountains:

We have information, derived from our scouts, that Big Creek Gap is evacuated. This information is confirmed by a deserter from General Stevenson, who also gives a rumor that Cumberland Gap is also evacuated. I am inclined to corroborate this rumor, inasmuch as the air was filled with smoke on yesterday for a circumstance of 15 to 20 miles from Cumberland Gap, which was probably caused by burning timber, in order to create a curtain of smoke behind which to retreat. However, I have sent reliable scouts to both of these points to ascertain the actual fact. If the enemy has retreated I shall march at once upon Knoxville and operate thence upon the rear of the enemy, who has probably gone toward Chattanooga.

GEORGE W. MORGAN,

Brigadier-General.

If this be true, whether the evacuation be temporary or permanent, it is probably the result of Mitchel's appearance before Chattanooga with a force the strength of which was not known to the enemy. I have ordered Morgan to seize the Gap if evacuated.

D. C. BUELL,

Major-General.

HUNTSVILLE, June 10, 1862.

Major-General BUELL:

I deemed it an important duty to drive the enemy back to Chattanooga. To do this we were obliged to advance to the ferry opposite that place.

My troops rendezvous at Fayetteville, and so cautious was I that I ordered one division of these troops to march to Winchester by way of Tullahoma, to make it impossible for any considerable force of the enemy to escape us to the north of Winchester. I ordered scouts to be sent out from Murfreesborough, Wartrace, and Shelbyville, to be certain that no considerable force of the enemy was to the north of Winchester.

I am certain that these troops, if they exist, never crossed the river at or near Chattanooga. I had already determined to occupy McMinnville, and to this end ordered the rebuilding of the bridges more than ten days ago. I have directed Colonel Lester, in case the troops are concentrated under his command, to find a position the holding [of which] will protect Shelbyville, Wartrace, and Mufreesborough.

From later intelligence I am led to believe that the large force reported does not exist; but, general, I deem it a matter of the utmost moment that a sufficient force shall promptly occupy the two avenues by which Middle Tennessee and Northern Alabama may be invaded. Since the fall of Corinth we surely have forces sufficient.

O. M. MITCHEL,

Major-General.