56 Notes upon the Geology of the Western States. 
stratified with the sandstone, and a few shells and corals are 
found in them ; and whenever the thin layers of limestone dis- 
appear, the same fossils are found in the sandstone. 'These char- 
acters are distinctly seen near New Albany, in the hills known 
as the Knobs, to the northwest of the village. 
‘Farther to the west and northwest, and above the nun 
extending along the Ohio, on: Kothcsidiepaind into the states of 
Illinois and Kentucky, there appears as a distinct and import- 
ant mass, a limestone resembling that interstratified with the 
sandstone just noticed. The lower part of this limestone is com- 
pact, very fine grained, and some portions fit for lithographic 
stones ; the upper part is coarser, often containing chert or horn- 
stone, en finally the uppermost layers are oolite. It everywhere 
contains the Pentremite and a peculiar coralline fossil, the Archi- 
medes of Le Seur, besides Cyathophyllum and several sheils of 
the genera Terebratula and Delthyris. On the Mississippi it con- 
tains two or more species of Productus, a large Delthyris, and a 
peculiar crinoidal fossil. In the oolitic portion, I saw a single 
species of trilobite and a few small shells. ‘This limestone’ can 
be traced along the Ohio, upon both sides, almost uninterruptedly 
as far as Leavenworth, fifty miles below New Albany; it there 
passes beneath the conglomerate, showing very clearly its posi- 
tion in regard to the latter and the Chemung group. Beyond 
this it does not uniformly appear; the conglomerate, and in some 
places, as at Hawesville, Ky., the coal formation coming to the 
level of the river. It reappears again about Shawneetown in 
Tilinois, and is visible on one or both sides, almost continuously 
to the mouth of the river. In ascending the Mississippi above 
the mouth of the Ohio, it soon appears, forming cliffs which, be- - 
low St. Louis, attain the height of from one hundred and fifty to 
two hundred and fifty feet above the level of the water. These 
cliffs are turned to very important economical purposes ; small 
buildings are erected upon the top, where lead is melted for shot 
making ; the cliff serves the purpose of a high tower, the shot 
being received below on the margin of the river. This limestone 
extends along the Mississippi to near the mouth of Rock river. ~ 
We have then throughout all this great extent of country, from 
central Indiana to beyond the Mississippi river, a limestone dif- 
fering entirely in all its most essential characters, and emphat- 
ically in its tea from any in New York. Among its fossils 
