Olil Ocean a^;;^j puilcjer 



the Latin for " shore " — are included all deposits 

 that lie on shore-lines, between the highest and 

 the lowest tides. 



At first sight the tide-deposits might seem to 

 be but a small matter. Not so small, really! 

 Earth's coast-lines reach to something like one 

 hundred and twenty-five thousand miles in length. 

 Since the medium breadth of ground affected by 

 tides is about half-a-mile, the whole tidal area 

 amounts to over sixty thousand square miles. 



No mean workshop this, under the auspices of 

 crushing and grinding billows. On shore-lines 

 building takes place rapidly. 



The " Shallow " zone is much more extensive, 

 reaching to some ten millions of square miles. 

 Its principal deposits are much the same as those 

 of the tidal zone — muds, sands, gravels, pebbles. 

 In parts of the Earth they also include volcanic 

 and coral muds. 



Greater, far greater, far more widely reaching, 

 are the regions of '' Deep-Sea Deposits," which 

 cover more than one-half of the whole surface of 

 our globe. 



In those cold and dark and silent workshops, 

 hidden from the eyes of men, building goes on, 

 very quietly, very slowly, through interminable 

 ages. In those workshops are deposited divers 



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