ae 
by LE. Cornelius. 219 
have a granite range on their maps, immediately west of the 
Blue Ridge; and even that mountain is on those maps, in some 
parts of it, covered with the granitic tinge. This may be true. 
Ican answer for only two points of it, and for that part of the 
country beyond, lying near the main road to Tennessee. In 
this route 1 descended almost the whole length of the great val- 
ley included between the Blue Ridge on the east, and the north 
mountain on the west. But inno instance did I meet with spcei- 
mens of granite; nor west of the Blue Ridge with any prevail- 
ing rock but limestone. I know of no reason why the Blue 
Ridge should not be regarded as the first great dividing line be- 
tween the granite and limestone countries. The change in the 
geological formation is so sudden, and striking, that it would be 
dificult for the most careless traveller with his 4 
observe it. The face of nature, he cannot but perceive, wears 
adifferent aspect; the air is more cool and lively; even the wa- 
ter which he drinks possesses new properties perceptible to his 
taste. The inhabitants no longer speak of their sandstone wa- 
;” but every where he hears of “ limestone water.” Indeed 
- 800 miles in the direction which I travelled, he tastes no 
other. water.. Every spring and "€ every rivulet, is strongly im- 
Pregnated with carbonate of lime. The vessels in which it is 
epared for culinary use, soon become lined with a white calca- 
reous_ crust. Nor is its taste the only inconvenience experien- 
ced by the traveller unaccustomed to it. It often injures the 
health of a egal and covers the surface of the body with cu- 
fancous eruptio 
Limestone country in inclined strata. 
The geological observer has now entered upon a very inter- 
esting field. Its great extent, and its wonderful uniformity, give 
new facilities to investigation. ‘Two divisions of it seem to have 
made in nature. 
The firs is that which iucludes the limestone reat in INCL 
ED STRATA. This division extends from the Blue Ridge, to 
the Cumberland mountain in East Tennessee, a distance in the 
tection of my route of 500 miles. Of course it includes all 
