OTHER EFFECTS PRODUCED. 45 



wards. To what cause this change is owing it is 

 difficult to guess; but it is an example of the 

 alternation of deposits from the action of the sea, 

 in circumstances apparently unchanged, and which 

 may afford cause for reflection to the geologist. 



A great variety of other instances might 

 be mentioned of such alterations on our sea- 

 shores, as occurring from age to age. The 

 western coast is less liable to such alterations, 

 because bounded to so great an extent by rocks, 

 the materials of which offer great resistance to 

 the most violent action of the sea. But on almost 

 all the western coasts, wherever the shores are 

 low or are formed of materials liable to be easily 

 acted on by the waves, great changes have taken 

 place, in some instances extensive tracts having 

 been swallowed up by the waters, and in others 

 great additions by the deposition of the soil being 

 made to the extent of the sea-shore. 



But the waters of the ocean and the force of the 

 winds produce other alterations in the aspect of 

 the sea-shore than those now described. In some 

 instances, where the beach is low, the waves cast 

 up mounds of gravel, formed of stones of various 

 kinds, rounded by being constantly rolled upon 

 each other ; and these, during the prevalence of 

 storms, and where the shores are exposed to strong 

 currents from either side, are swept along, varying 

 their quantity in different localities as the effects 

 of the impelling forces are modified by the form 

 of the shore itself. In other instances, where the 

 water is comparatively shallow, the waves during 



