The Mighty Deep 



Not indeed generally to her deepest parts. 

 So far as we yet know, the Ocean does not 

 build continents in those black profound abysses, 

 miles deep, flat-floored, calm, unchangeable. No 

 traces have been there discovered of such strata 

 as form the Continental parts of Earth's Crust. 

 Ocean's main work, as builder, goes on in '' The 

 Transitional Area ; " and most so in that part of 

 it which is called '' The Continental Shelf," where 

 the depth does not exceed about six hundred 

 feet. 



** Transitional " regions are so named because 

 it is believed that some of them may once 

 have been Continents, that others of them may 

 yet become Continents. There was a time, in 

 the long past, when ocean-waters flowed over 

 all those parts of Earth which now are known 

 to us as dry land. There may be a time, in the 

 far future, when areas of comparatively shallow 

 water will become dry land. 



Through ages the task of taking materials from 

 the land for building purposes has been carried 

 on by the Ocean, and it goes on still. The 

 Continents are being steadily worn away ; the 

 Islands are becoming continually smaller. 



Were this to continue always, with no counter- 

 acting forces, islands and continents must in the 



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