SCENOGRAPHICAL GEOLOGY. 



627 



a plateau of older formations of schists entirely isolated from any other 

 deposits of the same age, yet with highly inclined strata. These are, 

 unlike the sugar-loaf mountain 

 structures, composed of nearly 

 horizontal strata, which have 

 been rounded by erosion. 

 These elevations, like the lat- 

 ter, are relics of a once wide- 

 spread blanket of rock; but 

 the fragments have been doub- ^ 



led up by plicating forces, and c 



oo 

 their former connection seems 



difficult to believe. Their pres- 

 ent separation is not due to 

 erosion alone. It is also likely 

 that there have been some 

 special uplifts of land in con- 

 nection with each of these 

 summits. In New Hampshire 

 these mountains are likely to 

 be confounded with those of 

 granitic origin, like the Strat- 

 ford peaks. 



I do not need to speak fur- 

 ther of our ravines and gorges, 

 as the most prominent ones 

 have been described. Fig. 

 88 may illustrate some of our 

 broad, sloping valleys, where 

 level plateaus have been form- 

 ed by the transportation of 

 drift material. Our greater 

 valleys of this sort are too 

 extensive for representation. 

 Such are the Conway plains, 

 the barren expanse in Madison and Ossipee, and many other districts 



