68 



Feather stonhaugh^s Geological Report. 



midal peaks, which time, and the abrasions consequent upon 

 their upraising, have worn into their present forms, were 

 once, in part, many thousand feet beneath the now lateral 

 surface of the stratified beds they have thrown into this high 

 inclination. These sections show that mountainous chains 

 may have been upraised at any of the periods belonging to 

 the succession of strata, and that each period may have its 

 peculiar system of mountains. To a great extent, this has 

 been found to be the case, and geological periods of elevation 

 can be distinguished, establishing, not chronologies belonging 

 to the present order of nature, but to the great history of sub- 

 terranean dynamics, to which the present varied form of the 

 earth must be referred, modified, as it has often been, by the 

 action of the waters invariably displaced by these elevations. 

 The practical uses to be derived from the detailed geological 

 examination of mountains and ridges are numerous. Where 

 any chain or series of parallel ridges is productive of useful 

 metals, combustibles, or mineral bodies, all its parts may be 

 investigated w4th a view to trace its continuities ; and by con- 

 necting distant points having the same mineral structure, 

 depositee may be identified, known in some localities to be 

 productive. The series of Alleghany ridges, hereafter to be 

 spoken of, are a proper field for the exercise of these inves- 

 tigations. 



It is deserving a remark here, that some geologists in 

 Europe who have bestowed much investigation on this sub- 

 ject, have supposed that mountain chains elevated at the same 

 period of time have a general parallelism in their magnetic 

 bearing. It has been already stated that many of the tran- 

 sition chains of Europe trend from northeast to southwest, 

 which is the general direction of the series just spoken of. 

 If this conformity of bearing could be established, it would 

 lead to speculations on the laws of the elevating power, and 

 perhaps eventually open the way to an explanation of the 

 principle upon which the structure of anticlinal rocks depends. 



