TACONIC QUESTION IN GEOLOGY. 219 
Eaton, what he called the Sparry Lime-rock, found at the summit of the First Gray- 
wacke, to the east of the Hudson. In the same division also was included a group of 
strata lying to the west of Lake Champlain, which he designated the Calciferous Sandrock 
and the Metalliferous Lime-rock. In this latter region, however, these Transition lime- 
stones were found to rest directly upon the lower division of the Primitive series; the 
whole of the intermediate divisions being absent. 
§ 7. The Transition limestones in this western area were, according to Eaton, directly 
followed by the third or Lower Secondary series, the first division of which (III. 1) was 
described as an argillite or graywacke-slate, and the second (III. 2) as a sandstone or mill- 
stone-grit; the two together making what he called the Second Gray wacke; declared by him to 
be indistinguishable from the First or Transition Graywacke, except by the fact that it over- 
lies the Transition limestones. This Secondary Graywacke is thus clearly identified with 
the strata subsequently called the Utica slate, the Pulaski or Loraine shales, and the 
Gray or Oneida sandstone. Succeeding it, were the Lower Secondary limestones, including 
the Niagara, and the Lower and the Upper Helderberg divisions, of later geologists. The 
Medina, Clinton and Onondaga divisions were looked upon by Eaton as constituting 
subordinate intercalated series. 
For the understanding of the problems before us, we need not follow our author 
above the Second Graywacke; though it is important to remark that he first showed that 
the Lower Secondary limestones underlie alike the bituminous coal and the anthracite of 
Pennsylvania, both of which he placed in the Upper Secondary series ; thus correcting the 
error of Maclure, who had assigned the anthracite to a lower horizon, and placed it in the 
Transition series. 
The subsequent study of the Taconic question will be much facilitated by keeping 
in view the classification and the definitions of Eaton, the abandonment of which materi- 
ally retarded the progress of American geology. Some of his once rejected views are now 
-universally accepted, and, in the opinion of the present writer, a similar vindication 
awaits the entire succession defined by Eaton, so far as his Primitive, Transition and 
Lower Secondary series are concerned. The relations of these will be farther shown 
below, in a table at the end of the next chapter. 
II.—THE GEOLOGICAL SURVEY OF NEW YORK. 
§ 8. Such was the state of our knowledge of those rocks in 1832. Five years later, 
the geological survey of New York was begun. The Northern district of the state was 
then assigned to Ebenezer Emmons, a pupil of Eaton, and to him we owe the present 
nomenclature of what he called the Champlain division of the New York system of paleo- 
zoic rocks ; described by him as resting, in that region, directly on the Primary series, and 
designated as follows, in ascending order: 1. Potsdam sandstone; 2. Calciferous sand- 
rock (now known to be a dolomite or magnesian limestone); 3. Chazy limestone; 4. 
Trenton limestone, with its subdivisions, the Birdseye and Black-River limestones ; 5. 
Utica slate; 6. Loraine shale; 7. Gray sandstone; 8. Medina sandstone. The numbers 
7 and 8 were, as is well known, subsequently separated from the Champlain division, 
and joined to what was called the Ontario division of the New York system. 
§ 9. This order was evident to the west of Lake Champlain, where the strata are 
