1 Dzvellers of the Sea and Shore 



cove; so, while the land is being destroyed in one place, 

 it is being formed anew in another. To a greater or 

 lesser extent similar changes are constantly taking place 

 in the shore lines of every seacoast in the world. If we 

 were to travel along either of our long coasts, we 

 should find that the sea seems to be wearing the hills 

 away more effectively in some places than it does in 

 others. This is due to several causes, chief of which 

 are the shape of the shore and exposure to the waves. 

 But the work of destruction is always going on; like- 

 wise, the work of replacement. In some regions, in 

 fact, the land is being replaced at a rate for which there 

 is not at present any explanation. Many of those great 

 stretches of wide, sandy shores bounded by "dunes" 

 are cases in point. Where all the material came from 

 for those vast quantities of sand, and which is ever in- 

 creasing, is one of the ocean's mysteries. 



If we take up a pinch of sand from any beach and 

 examine it under a strong glass, it will be found that 

 the separate grains are not worn smooth and round, as 

 we might have expected, but that they retain to some 

 extent their original sharp, angular appearance. This 

 is because the grains, as they are washed about, lie 

 with their faces toward one another with a film of 

 water between them. The film acts as a protection, 

 preventing them from actually coming into contact and 

 so grinding off each other's angles. Now desert or 

 wind-blown sand grains show a quite different charac- 

 ter. Their unprotected edges are rounded, and many 

 of them are worn so small that they are in reality 

 nothing more than fine particles of dust. 



Where new land is forming on a coast, the shore 



