98. Geoxogx of Natchez. 
The following information on 
the cliffs of clay on which Natch- 
ez is situated was imparted to 
me this year by Dr. James Smith 
of Baltimore. 
These cliffs are about £20 feet 
high in 5 strata. 
1. Soil 4 feet thick. 
£. Marly clay 80 feet thick. 
8. Bank of clay and shells £5 
feet; the shells are of several 
kinds, chiefly a white univalve 
like Helix but larger, and a bi- 
valve, both soft not flinty. The 
bivalve is a new Biclisma. B. tefes 
Raf. Subcylindrical, £ inches 
long, fulvous, breadth l-3d of 
length. 
4. Pure marly clay again 100 
feet thick. 
5. Bank of £0 feet down to 
the river shore, gravelly or clay 
mixt with rolled silicious pebbles. 
Many are of yellow Calcedony, 
black and red jasper, or some 
very curious stones, for in- 
stance. 
Gravel stone with impression 
of wood on it! 
Red and yellowish chert with 
impressions of shells. 
Fragments of pumice stone. 
Beautiful onyx pumice. Out- 
ward coat like iron grey horn- 
stone, compact smooth without 
holes, one line thick. Inside 
porose light with unequal holes, 
of a fine pu rple with shining vi- 
trified specks. Next a band of 
greenish and another rusty or 
brick color at the other end. 
Thus this fine stone has 4 colors, 
iron, purple, green, and rusty. 
Fragments of pseudo volcanic 
glass. One somewhat like jas- 
per was grey inside but shining 
black outside as if glazed. 
99. Geological Memarks between 
Buffaloe in Jfew Fork and 
Fittshurg , in Pennsylvania . 
By David Thomas. 
Buffaloe is on Lake Erie at 
the mouth of Buffaloe creek, in 
a level rocky plain extending 16 
miles E. The rock is limestone 
and horizontal, it extends to the 
Canada side where it is more 
broken. The valley of Buffaloe 
cr. is wide and of yellow clay i 
The shores of Lake Erie is low, 
of miry clay, mixt with sand and 
gravel. Three miles from the 
creek the soil becomes firm, and 
wells are dug under it in slate. 
The first bluff on the Lake is also 
of this slate or argillite. 
At eighteen miles creek, a thin 
stratum of limestone, which once 
overlaid the crumbling slate, has 
been broken into angular frag- 
ments with square edges to the 
margin of the Lake. The hills 
of slate begin to become steep; 
it is nearly black, resembling 
coal, but in thin lamina, some 
even flames in a hot fire, some 
are iridescent, or a yellow sub- 
stance is found between the 
leaves. 
Beautiful pebbles decorate the 
shore of the Lake, they are pri- 
mitive fragments of many colors. 
Springs of petroleum are found 
a few miles inland, and coal 
will perhaps be found hereafter. 
Many bluffs project in the lake 
in deep water, yet it is said that 
formerly there was a passage or 
road at their foot, and that the 
lake has encroached there. Pur- 
plish ferruginous sand is found 
on the shore between them. The 
bluffs are slaty and hardly 100 
feet high. Blocks of granite and 
limestone of many tons are nume- 
rous on the shore. Some singu- 
