GENERAL OBSERVATIONS. 409 



hardly at all altered, and which are Silurian, 'Devonian, and Car- 

 boniferous in age. 



There is, therefore, abundant reason for the inference that New 

 England is made up of Palaeozoic rocks. , The White Mountains of 

 New Hampshire are now believed to be formed of altered Devo- 

 nian strata. The gneiss quarries of Haddam, on the Connecticut, 

 probably consist either of Carboniferous or Upper Devonian depo- 

 sits ; for the graphite on the slabs sometimes has the form of the 

 stems of plants : one of them, fourteen inches long and one to two 

 wide, now in the Yale cabinet, is too plainly vegetable to be 

 doubted, though now deprived of its original markings. 



The conformity to the Appalachian system appears in, — 



1. A general parallelism of the outcrops to the Green Mountains, 

 the bands of rock marked on a geological map all having this 

 common course. 



2. A general prevalence of east-southeast dips over New Eng- 

 land, showing that there are here a series of decapitated folds, as 

 well as over eastern Pennsylvania and Virginia. 



3. The steepest side of the fold being the western, as follows 

 from the fact last mentioned. 



4. The flexures, fractures, and dislocations of the coal beds of 

 Rhode Island and the neighboring region in Massachusetts. 



Western New England received a part at least of its flexures 

 before the Upper Silurian era (p. 392). The rest probably dates 

 its upturning from the time of disturbance here considered. The 

 fact that the Coal formation is among the folds proves this for a 

 large part of New England. Between these beds and the Devo- 

 nian of eastern Vermont the rocks are probably either Carboni- 

 ferous or Devonian ; and the whole probably participated in these 

 changes. 



In Nova Scotia and New Brunswick there are other examples of 

 folded Carboniferous, Devonian, and Silurian strata, sustaining the 

 conclusions deduced from the regions to the southwest. 



Thus, the whole Continental border from Alabama to Newfound- 

 land participated in these grand movements. The facts mentioned 

 do not prove that the production of the flexures in the strata was 

 necessarily accompanied by the emergence of the Appalachian 

 region. 



2. Alterations of rocks. 



The alterations which the rocks underwent at the time of these 

 disturbances are as follow : — 



1. Consolidation. — Strata were consolidated; for the rocks of the 



