Bache, of the topographical engineers, and called for by a resolution of the House of Representatives of the 3d of March, 1831.

Report of a reconnoissance and a preliminary survey between the Savannah and Tennessee rivers, by Major H. Bache, United States' topographical engineer, January 18, 1832.

Lieutenant Colonel J. J. ABERT,

Topographical Bureau.

SIR: In obedience to the instructions of the Engineer Department of the 12th June, 1828, requiring examinations and surveys to be made to ascertain the practicability and the nature of a communication to connect the Savannah and Tennessee rivers, I have the honor to present the following report, accompanied by plans and profiles, numbered each from 1 to 5, and a map exhibiting the deep cut, and feeders proposed for the supply and passage of the summit.

Any system of communication to connect the Savannah with the Tennessee, must proceed from Andersonville, at the junction of the Toogaloo and Seneca, the highest navigable point on the Atlantic side. For this purpose three different routes present themselves; namely, by the head branches of the Savannah river to the Hiwassee, Little Tennessee, and French Broad rivers, respectively, tributaries of the Tennessee.

As

The general opinion entertained of the difficult character of the country in the first direction, and the favorable account received of the two latter routes, particularly that by the Little Tennessee, offered, when the smallness of the party was considered, every inducement for their prior examination. the practicability of a communication in this direction, between the Atlantic and the waters of the Mississippi, depends upon the ability to pass the mountains, the examinations and surveys were confined to that section of country embraced by Walton's ford on the Toogaloo, and the head of the Seneca, on the Atlantic side, and Russell's ferry, on the Little Tennessee, and Dandridge, on the French Broad, on the side of the tributaries of the Mississippi, leaving the extension of the surveys, should the results now presented render such a course desirable, to future operations.

The main feature in these routes, as in every other between the waters of the Mississippi and Atlantic, is the elevated region designated further north as the Alleghany, and in this section of country as the Blue ridge, and the Smoky or Unakoy mountain, which prolong the general course northeast and southwest of the whole chain. The breadth of this elevated region by the Little Tennessee route, from Walton's ford, on the Toogaloo, to Talassee, upon that river, is about 113 miles. Proceeding westwardly, the greatest elevation at the summit of the Blue ridge is attained in about thirty-five miles, whence, by the Little Tennessee and French Broad, the descent is

route, would doubtless be successful. The timber consists of many kinds applicable to the construction of bridges, rails, &c.; namely, red, white, and black oak, black and white hickory, poplar, black walnut, chesnut, locust, gum and pine; the latter being found only in the lower districts of the mountains, on both the eastern and. western faces.

As already remarked, the routes examined were two. First route, from the mouth of Panther's creek, assumed as the point of departure, by the Toogaloo and Chatuga rivers, and Chechero and Stekoa creeks, to the summit; thence, by the Little Tennessee, to Russell's ferry. Second route, proceeding from the west from Dandridge, Tennessee, to the source of the French Broad, by the west fork and Abraham's branch, to the summit; thence, by the Frozen branch, main fork of the Toscaway, the Toscaway itself, and the Keowee, to its mouth.

Simultaneously with the examination of these routes, it was deemed advisable to enter upon a preliminary survey of the first, with a view to general results, as that route was represented to offer the greatest facilities for the junction of the Savannah and Tennessee waters. For the convenience of description, the subdivisions will be made less with reference to extent, than to the characteristics of each.

PRELIMINARY SURVEY OF THE FIRST ROUTE.

SUBDIVISION FIRST.

From the mouth of Panther's creek, by the Toogaloo and Chatuga, to the mouth of Lick-Log creek. Distance, 6.75 miles; ascent, 137.77 feet; ascent per mile, 20.41 feet; locks 17; general course, north, circuitous and moderately serpentine.

Commencing at a point on the east side of the Toogaloo, the ground is generally favorable for 0.9 of a mile, it being table land, and for the most part cultivated; then for 0.6 of a mile the hills encroach upon the river, rising at angles varying from 10° to 45°. The character of the ground for the next C.6 of a mile is cultivated table or flat land. The line now crosses the river at a point where it turns suddenly to the right, and pursues the west shore for 1.5 miles along hill sides, at angles from 10° to 60°, when the ground becomes favorable for 0.2 of a mile: then rocky bluffs for the same distance, succeeded by table land for 0.9 of a mile; partly cultivated. The next 0.1 of a mile is hill sides of about 25°, succeeded by 0.6 of cultivated table lands; thence, to the mouth of Lick-Log creek 1.1 of a mile, through hill sides of from 25° to 50°, and rocky bluffs.

With the exception of the table land, the ridges, running transversely to the direction, project quite into the stream, in some places exhibiting rugged and precipitous fronts. The largest portions, however, of the margins of the river possess more the appearance of elevated grounds, skirting streams whose general course is more nearly parallel to, than across the direction of the ridges.

It is believed that the line of levels will not vary much from the final trace of any work for this subdivision; the course selected on each side of the river being essentially more favorable than any that would be found on the opposite. The erection of any work for crossing the mouth of the Tallulah, which empties into the river from Georgia, will considerably in

object in view, will enable a just discrimination to be made of the facilities afforded by each, inducing, probably, the crossing of the river in one or two nstances to take advantage of the more favorable side. Indeed, from the serpentine course of the river within the above limits, forming at times short turns, this may become an expedient of absolute necessity to soften as much as possible the abruptness of the curves, should a railroad meet with most favor. Should such a course become necessary, the narrowness of the main stream, and the very limited rise in the freshets, would render the construction of aqueducts or viaducts of easy accomplishment, and comparatively at little expense. These, and other questions of a similar nature, can alone be determined by other and more minute surveys.

SUBDIVISION THIRD.

From the mouth of Chechero creek, by the Chechero, to the mouth of Stekoa creek. Distance, 5.45 miles; ascent, 447.34 feet; ascent per mile, 82 feet; locks, 56; general course, north 30° west, direct and serpentine.

The great elevation in this distance, and the difficulties of the ground, combine to render this subdivision one of extreme difficulty. With the exception of about a fourth of the distance, the mountains rise abruptly from the water's edge, and the small proportion of favorable ground can only be taken advantage of by crossing the stream several times. proper points of crossing can only be decided upon by a more minute exami

nation.

The

The ground may be thus described: 1.5 miles hill sides to water's edge, angle from 10° to 60°; table land, cultivated for 0.5; hill sides less abrupt for 1.1 miles, the angles of whose slopes, near the water's edge, range from 10° to 30°. Another portion of cultivated table land succeeds, in extent, 0.4 of a mile, and 0.8 is followed by steep hill sides, at angles from 25° to 70°, which, after 0.1 of cultivated flat land, closes in again at these abrupt angles for 0.7 of a mile more, which, however, subside in the next 0.1 to slopes of 10° to 15%. The remaining distance of 0.3 of a mile to the mouth of Stekoa is favorable ground.

The great rise in this and the preceding subdivision renders a resort to stationary power absolutely necessary. For this purpose, the elevation being by three unequal steps of 241 feet in 1.4 miles, 33 feet in 1.3, and 173 feet in 2.7 miles, two inclined planes for the first, and one for the last, would be sufficient. It will be perceived, that, although the average rise is not too great to allow sufficient room for the necessary number of locks, yet the excessive rise in the first 1.4 miles will make this arrangement difficult, and only applicable to the case, by the adoption of the expensive system, particularly so when applied to the ground in this instance of lateral basins.

SUBDIVISION FOURTH.

From the mouth of the Stekoa, by that stream, to a point 550 feet above Star branch. Distance, 3.9 miles; ascent, 75.19 feet; ascent per mile, 19.27 feet; locks, 9.5; general course, south 75° west, direct and tolerably serpentine.

This subdivision comprises that portion of the Stekoa which runs nearly parallel to the Alleghany, and is strongly contrasted in the nature of its valley with those of streams flowing transversely to the ridges. The abrupt ascent of the next subdivision, in which the Stekoa suddenly resumes the usual