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[AsSfiMBLT 
sits of tufa, when practical attention shall be given by the farmers to 
the improvement of soil by the use of lime, will, from their great abun- 
dance, purity and ease of access, have that value given to them which 
they justly merit. 
On Frankfort creek, above the upper furnace, there is a deposite of 
tufa in hard or tough, though in thin layers. It is burnt for lime and 
carried to Utica. It makes the whitest lime I have yet seen in the 
State. 
TJ'p'per Limestone. — The last of the series but one of the rocks of Her- 
kimer county, is the upper limestone, embracing the cornitiferous, the 
geodiferous and the calciferous masses of Prof. Eaton; distinctions high- 
ly characteristic to the western part of New- York, but of no application 
in this; the fossils, relative position and general composition, being the 
primary characters. In the abundance and great variety of lapideous fos- 
sils, such as sea shells, corallines and crinoidea, we are presented with 
a character which strongly contrasts with the water limestone, the red 
shale, or any of the lower masses, with the exception of the Trenton 
limestone and the shales of Salmon river. In this limestone there is 
a more determinate arrangement of the different fossils, a creation as it 
were by families, than is to be found in any of the preceding rocks. 
Thus different species occupy different layers, each in countless myriads, 
and extending over a considerable extent of country. A whole race, 
seeming to be limited to a few contiguous layers, disappearing with 
those layers; to these other fossils succeeded, they in their turn giving 
place to a new creation, and for many repetitions during the deposition 
of this rock. 
The limestone forms the surface of the southern part of Herkimer 
county, extending from its irregular boundary line into some parts of 
Otsego. It is from six to eight miles wide, forming a part of the great 
range of limestone which extends from Niagara river to the Hudson 
unbroken, excepting by the action of water, of which, with some ex- 
ceptions, it forms the great dividing line between the Delaware and the 
Susquehanna to the south, and the Mohawk and Lake Ontario to the 
north. 
The limestone is quarried in many places for building stone and for 
making lime. 
Pyritifercms Rock. — This rock covers and conceals the limestone to 
the south of the county. It is the terminal mass north of the lowest of 
