THE GREAT OCEAN. 361 



for its indisputably continued growth and increase * ; 

 and tlie ocean between the tropics seems to us to 

 be a great cliemical laboratory of nature, where 

 she confides an important office in the system of 

 her economy to these imperfectly-organized animals 

 that produce lime-stone. Objects, it is true, ap- 

 pear magnified in proportion as the eye is near 

 to them, and he who, in the midst of these islands, 

 contemplates their formation, may be disposed to 

 assign to it greater importance in the history 

 of the earth, tlum the reality justifies. An ac- 

 curate description of the state of these reefs at 

 different periods, for instance, at an interval of 

 half a century, if it were possible and really under- 

 taken, must contribute to throw light upon many 

 points of natural history. 



It is to be observed, that the low and small 

 points of land which belong to this formation, have 

 no influence on the atmosphere. The constant 

 wind sweeps over them unchanged, as over the 

 inibroken surface of the waters. They cause no 

 precipitation of water or dew, and though we 

 paid the greatest attention, we never observed in 

 them the phenomenon of the mirage, which their 

 Hat profile is peculiarly w^ell adapted to render 

 evident to the eye. As an exception from this 



* Captain Ross found in Possession Bay, in 73° 39' north 

 latitude, living worms in the mud, wliich he drew up from a 

 depth of one thousand fathoms, and the temperature of which 

 was below the freezing point. 



