For the better understanding of the campaign, I submit a brief outline of the topography of the country from the barrens of the northwestern base of the Cumberland range to Chattanooga and its vicinity.

The Cumberland range is lofty mass of rocks, separating the waters which flow into the Cumberland from those which flow into the Tennessee, and extending from beyond the Kentucky line, in a southwesterly direction, nearly to Athens, Ala. Its northwestern slopes are steep and rocky, and scalloped into coves, in which are the heads of numerous streams that water Middle Tennessee. Its top is undulating or rough, covered with timber, soil comparatively barren, and in dry seasons scantily supplied with water. Its southeastern slope, above Chattanooga, for many miles, is precipitous, rough, and difficult all the way p to Kingston. The valley between the foot of this slope and the river seldom exceeds 4 or 5 miles in width, and with the exception of a narrow border along the banks is undulating or hilly.

The Sequatchie Valley is along the river of that name, and is a canon or deep cut, splitting the Cumberland range parallel to its length. It is only 3 or 4 miles in breadth and 50 miles in length. The sides of this valley are even more precipitous than the great eastern and western slopes of the Cumberland which have just been described. To reach Chattanooga from McMinnville or north of the Tennessee it is necessary to turn the head of this valley by Pikeville and pass down the Valley of the Tennessee, or to cross it by Dunlap or Therman.

That part of the Cumberland range between Sequatchie and the Tennessee, called Walden's Ridge, abuts on the Tennessee in high, rocky bluffs, leaving no practicable space sufficient for a good wagon road along the river. The Nashville and Chattanooga Railroad crosses that branch of the Cumberland range west of the Sequatchie, through a low gap, by a tunnel, 2 miles east of Cowan, down the gorge of Big Crow Creek to Stevenson at the foot of the mountain, on the Memphis and Charleston Railroad, 3 miles from the Tennessee and 10 miles from Bridgeport.

Between Stevenson and Chattanooga, on the south of the Tennessee, are two ranges of mountains, the Tennessee River separating them from the Cumberland, its channel a great chasm cut through the mountain masses, which in those places abut directly on the river.

These two ranges are separated by a narrow valley, through which runs Lookout Creek.

The Sand Mountain ins next the Tennessee and its northern extremity is called Raccoon Mountain. Its sides are precipitous and its top barren oak ridges, nearly destitute of water. There are but few, and these very difficult, wagon roads, by which to ascend and descend the slopes of this mountain.

East of Lookout Valley is Lookout Mountain a vast palisade of rocks rising 2,400 feet above the level of the sea, in abrupt, rocky cliffs, from a steep wooded base. Its eastern sides are no less precipitous. Its top varies from 1 to 6 or 7 miles in breadth, is heavily timbered, sparsely settled, and poorly watered. It terminates abruptly upon the Tennessee, 2 miles below Chattanooga, and the only practicable wagon roads across it are one over the nose of the mountain, at this point, one at Johnson's Crook, 26 miles distant, and one at Winston's Gap, 42 miles distant from Chattanooga.