HOW CORAL GROWS. 151 



nut and palm trees. Such romantic scenes, however, are not for 

 this world, and the plain dull truth is simply this, that the 

 Islands are not sinking, that the reefs do not require to be 

 brought up to the surface, and that, not only are the insects not 

 required, hut they are also as incapable of the herculean task 

 "which the Doctor assigns to them, as a starfish or a 

 sponge. 



We assert that the reefs never were connected with the 

 islands, hut that they are formed in a similar manner to the 

 bars at the mouths of rivers or harbours, or the sand bars of 

 islands on the North American coast such as those of Sabl 

 Island which are formed where the wash, and the undertow 

 from the shore, meet. To explain more fully. The bottom of the 

 sea is composed of material and formations similar to the surface 

 of the dry land. Both have their valleys, rocks, hills, and moun- 

 tains. The higher mountains which rise above the level of the sea 

 must form islands ; such as St. Helena, St. Thomas, the Azores, 

 the Bermudas, and Sable Island. What are called coral islands 

 then, are no more formed wholly of coral, than any of the 

 dt In rs. The parts formed of coral are probably only the reef 

 on, and outside of them. Comparative quiet is needed for 

 mineral formations, therefore the fringes could not form 

 on shore, as the surf by continually dashing on it, caused 

 too much disturbance. But where the wash and undertow 

 met, there would be an accumulation of the necessary 

 material, and all the tranquility that is requisite. Thus 

 count for the reef outside the island, and once that 

 reef is properly filled in solid, sufficient to intercept the inrol- 

 ling sea, another reef by the same action of wash and undertow 



