CHEMUNG COUNTY. 479 
great, numbers of loose masses containing the fossils of this group, probably washed down 
from the tops of the hills in the vicinity. 
The shaly rocks of this county are often highly charged with iron pyrites, which on decom¬ 
position stains the shale of an iron rust color. The same gives origin to numerous small 
beds of bog ore, which occur in many localities. One of these near Elmira, and another at 
Bigflats, furnishes a tolerably pure ore, but in most places it appears as a ferruginous tufa. 
On the southern margin of the county, in Southport, there is a small deposit of bog ore, which 
apparently owes its origin to the destruction of the conglomerate of the Carboniferous system. 
Several beds of shell marl were noticed in this county, and it is probable that further search 
will develop more extensive deposits of the kind. 
There arc several beds of marl near Millport, and the water rising in some of the springs 
is so highly impregnated with calcareous matter, that on standing a few hours, a thin deposit 
is formed. There is also a deposit of this kind about two miles northeast of Johnson’s settle¬ 
ment. In the town of Dix, at the Beaver dam, there is an extensive deposit of marl which 
is burned for lime ; it is first cut out in large square masses, which cohere on drying, and it 
is then placed in the kiln. There is also a similar bed of some extent near the Horseheads- 
Shells of Helix, Limnea, Planorbis, Cyclas and others are abundant in the two last named beds. 
The topography of this county is very simple. The Chemung river passes through its south 
western part, and opens a broad and beautiful valley, bounded by a range of hills, which are 
only broken by the lateral streams flowing to the river. The rocks on one side sometimes 
approach the river, while on the opposite is an extensive flat or bottom. Here, as elsewhere, 
the rocks on both sides of the valley bear evidence of erosion, and show that this river, as 
well as other streams, flows in a bed once occupied by rocks like those of the mountain mass. 
The eastern boundary of the county is along the valley of Cayuta creek, which has its 
origin in the small Cayuta lake, in the north part of the county, and forms a continuous 
valley thence to the Chemung river. Wynkoop’s and Baldwin’s creek form valleys of less 
importance. 
The Chemung valley, extending from the head of Seneca lake to the Chemung river, is the 
most prominent feature in the county. It offers the only route by which a canal could have 
been constructed, being through its whole extent alluvial, and presenting no remarkable ele¬ 
vations. The ascent from Seneca lake to the summit level of this canal is four hundred and 
forty feet in a distance of fifteen miles. 
