243 Remarks on the Geology of Western New YorTc. 



to make, as well as from the published descriptions of Prof. Eatorr 

 and others, I cannot resist the conclusion, that all these rocks are 

 older than the secondary formation, and owe their origin to that train 

 of causes, whatever they were, that produced the transition rocks. 



The metalliferous limestone of Eaton, which occurs at Trenton 

 Falls, and extends to the east end of Lake Ontario, seems to be 

 well characterized as the lower transition limestone. It contains 

 several species of the trilobite family, and other characteristic fossils. 

 It passes under graywacke on the south, which in its turn, is over- 

 laid by a conglomerate rock, or millstone grit. Then comes the 

 saliferous rock, so important to the economy and commerce of this 

 State, overlaying the millstone grit, and by its northern outcrops 

 forming the southern shore of Lake Ontario. If the views here en- 

 tertained are correct, this saliferous rock must be considered equiva- 

 lent to the old red sandstone of European writers ; separating as 

 it does through its whole extent, the lower from the upper transition 

 limestone. Wherever I have had an opportunity of examining its 

 strata, they have an evident dip towards the south. In structure, it 

 varies from a fine grained sandstone to- a soft shale, or slate ; and in 

 color, from red to a dull green. Although it forms the floor of the 

 salt springs at Onondaga and several other places further west, I see 

 no reason to conclude that this rock contains the mineral salt itself, 

 or that it is the only source from which it is derived. But from the 

 'fact that brackish springs, or "licks," as they are called in the west- 

 ern country, issue from some of the superincumbent strata, I should 

 conclude that it acts as a vast reservoir — collecting the water which 

 has become impregnated with the salt in passing through some of 

 the superior formations. In. Ohio .and Pennsylvania, the saliferous 

 rocks underlay the bituminous coal formations. Their general dip 

 there also is towards the south, or southwest, while at some places 

 they are pierced, by boring at a depth below the present surface of 

 the ocean. The'^thought has often struck me, (and I see nothing 

 improbable in the supposition,) that the saliferous rocks in Ohio, 

 Pennsylvania, and New York, belong to one vast, continuous for- 

 mation, having its northerly termination and outcrop in the latter 

 State, on the shore of Lake Ontario. 



Lying upon this sandstone, or separated from it by shale, contain- 

 ing layers of argillaceous iron ore, is that vast calcareous formation, 

 which presents so conspicuous a feature in the geology of this dis- 

 trict. It extends through the western part of this State, having its 



