THE COKALS AS BUILDERS. 213 



by making it a law of their existence not merely that they shall 

 be constantly under water which is clear and of a temperature of 

 not less than 68° Fahr., but that the water shall be aerated; the 

 ceaseless dashing of the waves against the rocks and reefs on the 

 windward side saturates tlieni with air, as the foaming breakers 

 and sparkling spray clearly indicate; and hence it is that here, 

 in the ever seething, boiling, foaming waters, these silent, unob- 

 trusive and seemingly unimportant creatures, with a lineage 

 reaching back to " chaos and old night," are found in the great- 

 est numbers, reach their highest development, and accomplish 

 the best results Thus do the ocean depths below us, where by 

 an alchemy far surpassing the skill and genius of man, the little 

 corals secrete from the ocean waves the limestone foundations for 

 islands and continents that are yet to be, equally with the depths 

 above where suns and systems of worlds revolve, forever reveal 

 to the observing eye and inquiring mind the perfect and profound 

 wisdom of their common Creator. 



We have spoken of the corals as builders, and in practical re- 

 sults, such they pre-eminently are, but, as Prof. Dana has shown, 

 they do not labor like the bird in constructing its nest or the 

 beaver in making its dam, but, by a law of their nature, they se- 

 crete the corallum or coral as man makes his own bones or the 

 oyster its shell, and the vast coral formations found upon the 

 land and in the ocean are composed of the skeletons which they 

 have left behind them. 



No costly sarcophagus of deceased royalty — no mausoleum 

 which human skill and ingenuity has ever erected — no Egyptian 

 pyramid rising grandly out of tiie shadows of four thousand de- 

 parted years, can even in a remote degree rival in beauty and 

 sublimity the vast and varied tumuli of these little dwellers in 

 tropical and semi-tropical seas. 



The corals and corallum in extensive beds abound in the Ba- 



