INTRODUCTION. 
43 
map of the State, but it is still insufficient for that purpose. As many of 
the data, however, have an interest by themselves, a portion of them are 
given here. They are derived from various sources, besides the observa- 
tions made in connection with the Geological Survey. A large part of 
the mountain region of the State has been triangulated, (partly by Prof. 
Guyot, and partly by the Survey), in a sort of secondary system, so as to 
locate, at least approximately, the prominent points and features with re- 
spect to each other, but as observations of that sort will be of little gen- 
eral interest, apart from their mapped results, that portion of the work is 
reserved for a future volume. 
Elevations — The altitudes given below are derived in part from rail- 
road levels, and in part from barometrical measurements, (both mercurial 
and aneroid), from railroad benches, and partly from the latter with the 
aid of the barometer and pocket level. These several sources will be in- 
dicated by the following abbreviations : Railroad levels, R. R. ; barometri- 
cal measurements, B. ; aneroid, A. ; barometer and pocket level, P. L. 
A large number of the barometrical altitudes in the mountain region I 
owe to the courtesy of Prof. Guyot, of Princeton, who has kindly com- 
municated to me many of his results in advance of their publication else- 
where, with the reservation that a few of them may possibly require cor- 
rection, to the extent of a few feet, upon a revision of the computations. 
And many of the measurements of the Survey marked P. L. are very 
rough approximations. 
It is not easy to classify these data. The grouping by orographic re- 
lations, adopted by Prof. Guyot, is perhaps the most simple and intelligi- 
ble, and will therefore be followed as far as practicable. 
ALTITUDES IN THE SMOKY MOUNTAINS. 
1. The part of the chain beyond the State line in Tennessee and Georgia, south of the Hiwassee River, 
called the Frog Mountains. 
B. 
B. 
B. 
B. 
B. 
B. 
B. 
P. L. 
B. 
P. L. 
P. L. 
Big Frog, (Ga.), 4,220. 
Cowpen, (Ga.), 4,146. 
Flat Top, (Ga.), 3,735. 
Flat Top, (Ga.), (east end, 3,576. 
Polecat Knob, (Ga.), 3,537. 
. .' W. N. Goss’ house, (Ga.), 1,987. 
Little Frog Mountain, Tenn., 3,349. 
Panther Knob, Tenn., 2,960. 
Duektown, Tenn., 1,780 
2. Between Hiwassee and Tennessee Rivers. 
Long Ridge, north knob, 3,373. 
Long Ridge, south knob, 3,273. 
Gcyot. 
Guyot. 
