548 



KEELING ISLAND. 



April, 1836 



one direction over a wide area, causes breakers, which even 

 exceed in violence those of our temperate regions, and which 

 never cease to rage. It is impossible to behold these waves 

 without feeling a conviction that an island, though built of 

 the hardest rock, let it be porphyry, granite, or quartz, 

 would ultimately yield and be demolished by such irresistible 

 forces. Yet these low, insignificant coral islets stand and are 

 victorious : for here another power, as antagonist to the former, 

 takes part in the contest. The organic forces separate the atoms 

 of carbonate of lime one by one from the foaming breakers, 

 and unite them into a symmetrical structure. Let the hur- 

 ricane tear up its thousand huge fragments ; yet what will 

 this tell against the accumulated labour of myriads of archi- 

 tects at work night and day, month after month. Thus do 

 we see the soft and gelatinous body of a polypus, through the 

 agency of the vital laws, conquering the great mechanical 

 power of the waves of an ocean, which neither the art of 

 man, nor the inanimate works of nature could successfully 

 resist. 



We did not return on board till late in the evening, as we 

 staid some time in the lagoon collecting specimens of the giant 

 Chama, and looking at the coral fields. Near the head of 

 the lagoon I was much surprised to find a wide area, con- 

 siderably more than a mile square, covered with a forest of 

 branching coral, which though standing upright was all dead 

 and rotten. At first I was quite at a loss to understand the 

 cause ; afterwards it occurred to me that it was owing to 

 the following rather curious combination of circumstances. 

 It should, however, first be stated, that corals are never able 

 to survive even a short exposure in the air to the sun^s rays, 

 so that their upward limit of growth is determined by that 

 of lowest water at spring tides. It appears from some old 

 charts, that the long island to windward was formerly sepa- 

 rated by wide channels into several islets ; this fact is like- 

 wise indicated by the less age of the trees in certain portions. 

 Under this former condition of the reef, a strong breeze, 

 by throwing more water over the barrier, would tend to raise 



