244 TOILERS IN THE SEA. 



tissues dwindle, and so render the old coral more 

 nearly solid. Then again, some little external assist- 

 ance is rendered by the mollusks, which adhere to 

 the dead trunk, as well as by the Nullipores which 

 grow over it, like the lichens on the trunk of an old 

 tree in a forest. Notwithstanding all their vicissitudes 

 in this " struggle for existence " the coral masses, and 

 coral reefs, must for ages have maintained their 

 position, in defiance of all their enemies, even 

 allowing for all loss by disintegration, a process so 

 continuous, and yet so small in its results, in com- 

 parison with the permanent mass, that it can scarcely 

 be taken into account as a disturbing influence. 



As we commenced this chapter by observations on 

 some strictures which had been made on certain 

 authors, on the grounds of scientific accuracy, so we 

 feel bound to conclude it by some strictures of our 

 own on the same grounds. Although it may be 

 permissible for a poet to use what machinery he 

 pleases, in the construction of his work, whether based 

 wholly, or only in part, on scientific fact, it is never- 

 theless imperative on one who writes in a scientific 

 work, assumed to give instruction in science, that he 

 should be accurate in his interpretations of the facts 

 of science. Whether this demand has been acceded 

 to in the work in question the following quotation 

 may determine. Writing of the coral animals this 

 writer observes : " Nothing can be more impressive 



