Coral Architects 



some of which are flung bodily upon it, while 

 others are pounded into sand, which fills up 

 holes and crevices. Gradually thus the whole 

 becomes cemented into hard reef-rock. 



As this goes on the low island slowly rises, 

 until it has climbed above high-tide level. 



Then the task can only be completed by waves 

 of exceptional reach. Still the grinding of coral 

 to fine sand goes on ; and in time it gains a 

 depth of some inches. And the waves carry 

 seeds and cocoa-nuts to the spot ; and shrubs 

 and trees spring up, to sow again their own 

 seeds, and by gradual decay to form mould. 

 Thus it comes about that a little island is made 

 ready for man to live on. 



One might expect these stages to be very slow 

 indeed, but such events march at the double in 

 tropical climates. In the Low Archipelago one 

 atoll was found, in the space of only thirty-four 

 years, to have been transformed from a mere 

 rock-reef to a lagoon island, fourteen miles in 

 length, with tall trees growing along almost the 

 whole of one side. 



As a specimen of the sizes to which coral- 

 buildings reach, the Maldive Archipelago may 

 be named. It is a vast collection of islands and 

 reefs, stretching to a length of four hundred and 



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