RECORDS LEFT BY THE SEA 



There is no sound, no echo of sound, in the deserts of the deep, 

 On the great grey level plains of ooze, where the shell-burred 

 cables creep. 



It is in these silent depths that for uncounted and in- 

 numerable years the crust of the earth has been forming 

 and has been growing outwards, while it has been slowly 

 hardening inwards above the fires of its unplumbed 

 interior. 



It has been calculated that in a square mile of the 

 ocean down to a depth of one hundred fathoms there 

 exist more than sixteen tons of carbonate of lime in the 

 form of the bones or shells of living animals. A continual 

 fine " snow-storm " of dead chalky animals is therefore 

 falling on to the bottom. Here and there, especially 

 among volcanic islands, portions of the sea-bed have 

 been raised up into land and masses of modern limestone. 

 Though these rocks are full of the same kinds of shells 

 as are still living in the neighbouring sea, they have been 

 cemented into hard rock. This cementing is due to the 

 water which has penetrated and permeated the stone, 

 dissolving chalky matter from the outside shells, and 

 depositing it once more lower down and farther in, like a 

 fine mortar, so as to bind the mass together. 



Every one has heard of coral reefs. They are one of 

 the best and most familiar examples of the way in which 

 great masses of solid rock can be built up by the dead 

 bodies of animals. In the warmer seas of the earth, and 

 notably in the track of the great ocean currents, various 

 kinds of coral polyps, as they are called, take root on the 

 edges and summits of submerged rocks and peaks, as well 



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