CORAL REEFS. 



CHAPTER II. 



CORAL REEFS. 



I HAVE told you that these strange little beings have 

 built up large islands and parts of continents, and I 

 hope with what I have said of their way of growing, of 

 their solid frame, and of their living in such crowded 

 communities, forming large, hard masses, you will be 

 able to understand how these busy little animals who, 

 in order to fulfil their appointed work have only to 

 grow have helped to make the world. 



We will suppose that under the level of the ocean 

 there is an island or a rocky hill growing up from the 

 bottom of the sea, which, if it became large and high 

 enough to be seen above the water, would be what we 

 call an island. Perhaps you think of the bottom of the 

 ocean as one great level floor (I remember I did, when I 



was a little girl) ; 

 but in the ocean, 

 as well as on the 

 land, there are hills 



No and valleys, and 



even mountain 



chains. Suppose, then, that there were an elevation 

 under the sea, which, if it rose higher than the water, 

 would be an island, but which stops at a depth of ten 



