414 A. Wing's Discoveries in Vermont Geology. 



Prof. Emmons describes the fault at Snake Mountain and gives 



m his American Geology (vol. I, Part 2, p. 87, 1855) ; hut 



i seems to have been taken north of the point described 



i«v h'. Wing; the place is not stated. # It makes the formations 



to the west of the fault lie in regular 'instead of inverted order; 



Professor Emmons supposed the rock of Snake Mountain, raised 



by the faulting, to belong to his Tannic System and therefore 



Prof Hitchcock, in the Vermont Geological Report, 



' i without the fault. 



the Geology of the part of 

 it investigated by him. 



1. The hydromica slates, clay slates, Eolian limestone and 

 quartzyte, with the so-called talcose conglomerate on the east, 

 are all of Lower Silurian age. and conformable in superposition. 



2. The Eolian limestone is not Taconic, as made by Prof. 

 Emmons ; nor of some one formation, as implied in > 



m the Vermont Eeport and in the name it gave it ; nor of the 

 Quebec group, as inferred by Loom,: it includes Lower Silurian 

 limestones of various periods, the Upper Potsdam or Lower Cal- 

 ciferous, Calciferous, Quebec, Chazy, Black River, and Trenton. 



3. The Red Sand-rock on the west of the Eolian limestone— 

 admitted to be Potsdam or Primordial in age — and the Quartz- 

 yte on the east which often rises into mountain ridges, are of the 

 same formation, and come nearly or quite together in Monkton, 

 on the northern limits of the limestone area. 



4. These rocks— the Red Sand-rock and Quartzyte— are the 



and eastern borders of a great abraded synclinal, the 

 axis " l ybi.h in its northern part has a slight northward rise 

 I dip), the sides there coming together; and which 

 also has both the eastern and western sides of the fold east- 

 lined, the dip of the beds being generally eastward. 

 borders there are, in some parts, subordinate longi- 

 inals and synclinals. 

 5 The slates of the "great central belt" are of the age of the 

 Hudson River slates (or that of the Cincinnati group), for- the 

 1 on page JJ4.3— which arc briefly "these : (1) the 

 I in several places on both the east and west 

 Sld es by 1; mUus, etc.), 



and di i where else have Trenton fossils been found in the Eolian 

 ; (2) there are also narrow north-and-south outcrops 

 fthe 



ring Trenton fossils 



: ,, 



underlaid by the limestone at its north end; 



v*) m Whiting the Trenton limestone of the Sudbury area has 



•nnection, across the si limestone of 



" ' '. ^ - :V . : '■.:-■■■ 



—•the slate being interrupted "for forty or fifty rods." 



