Cumberland Mountains, passing the Tennessee, turning and occupying Chattanooga, traversing the mountain ridges of Northern Georgia, and seizing the passes which lead southward have been enormous, and can only be fully appreciated by one who has personally examined the region. These difficulties are now all substantially overcome. The army is in the best possible condition, and is advancing with all the rapidity which the nature of the country allows. Burnside will secure its left flank, but a sudden movement of the enemy to its right would endanger its long and precarious line of communications and compel a retreat to the Tennessee.

To avoid this danger a column as strong as possible should be pushed eastward from Corinth. The advantages already gained are so great,and the possibilities of further triumphs so important, that I take the liberty of especially urging the subject upon your attention. Would it not be better even to recall Steele from Arkansas than to risk a check here, where heart of rebellion is within reach and the final blow already prepared?

[C. A. DANA.]

[Honorable E. M. STANTON,

Secretary of War.]

CRAWFISH SPRING, September 16-12.30 p.m.

Your dispatches concerning an obscure passage in mine of 12th, have just come to hand. The words not understood are:

It is probable,however, that before these dispositions are completed he will have got east of Pigeon Mountain and made good his escape to Rome. This region is composed of long mountains with few practicable passes. For instance, it is about 30 miles from the head of Lookout Mountain to the first gap. The roads are worse than those over any other mountains in the Union; not impassable, but very destructive to wagons.

This place is 13 miles south-southwest from Chattanooga. Weather pleasant.

[C. A. DANA.]

Major ECKERT.

CRAWFISH SPRING, September 16-1 p.m.

McCook mistook the order of march prescribed for him to concentrate upon Thomas; marched from Alpine around the southwestern flank of Lookout Mountain, coming down into this valley by way of Stevens' Gap, instead of moving directly northward and coming in by Dougherty's Gap. This mistake has caused two days' delay. Sheridan's division got down into the valley yesterday, and the others will get down to-day. The concentration of the army will then be perfect, McCook holding the right, as before, Thomas the center, and Crittenden the left, while Granger, with Steedman's division and Colonel Daniel McCook's brigade of the Reserve Corps, is posted at Rossville on the extreme left to guard the approach to Chattanooga from the direction of Cleveland and Ringgold. The concurrent testimony of spies and deserters shows that the enemy are concentrated at La Fayette. No re-enforcements from Virginia have yet arrived there, nor does it seem that any considerable body has reached Dalton. The present plan of Rosecrans is to hold gaps in Lookout Mountain in his rear, and to seem to threaten the gaps of