33 



CHAP. III. 



CHANGES IN OUR SEA-SHORES. 



Mutations of the Earth's Surface indicated by Geology. Genera 

 View of their Causes. Alterations which from age to age have 

 occurred in various Parts of the British and Irish Coasts, and 

 their Causes. Analogous Changes in other Parts of the World. 



THE phenomena with which the science of geology 

 is conversant afford unquestionable evidence that 

 in periods long antecedent to that which beheld 

 the present distribution of sea and land, a series 

 of stupendous changes took place on the surface 

 of our globe. Some of these changes may have 

 been effected with comparative rapidity, such as 

 those arising from the elevation of the igneous rocks 

 in a state of fusion ; but in general the process of 

 modification, must have been slow and gradual so 

 as to extend over many thousands of years. Of 

 this there is incontrovertible evidence in the fact, 

 that all the stratified rocks of whatever kind are 

 of aqueous origin, and were formed by processes 

 which could not be sudden, the disintegration and 

 wearing away of the primary rocks by the action 

 of water, the deposition of the various materials 

 of which they consisted at the bottom of the 

 sea, and their subsequent consolidation either by 

 physical or chemical causes, or by both in com- 

 bination. 



