THE FLOOR OF THE OCEAN 



By P. G. H. Boswell, D. Sc, F. R. S. 



Professor of Geology in the University of London, Imperial College of Science and 



Technology 



Although Kipling's village of Huckley, led by 'Dal Benzaguen 

 herself, may have voted that the Earth is Flat, it is undoubtedly a 

 fact that general opinion, outside perhaps Zion City, 111., holds to 

 the view that it is a globe. But undue satisfaction in regard to our 

 knowledge of this globe is hardly warranted when we remember that 

 three-fifths of its surface is almost unknown to us. For this large 

 proportion of the earth's crust (the lithosphere) is covered by the 

 oceanic envelope called the hydrosphere. The margins of the seas 

 have fluctuated since the earliest geological times and they fluctuate 

 to-day; as the sonneteer observed: 



When I have seen the hungry ocean gain 



Advantage on the kingdom of the shore, 

 And the firm soil win of the watery main 



Increasing store with loss, and loss with store, * * * 



And notwithstanding its imperfections, the geological record has been 

 fairly plainly written by these marginal fluctuations, but what lies 

 beneath the depth of the ocean, being invisible and only slightly 

 accessible, is still but little known. Yet when we are asked what 

 contribution the progress of science is making to deep-sea lore, we 

 can answer that during recent years significant advances have been 

 made in our knowledge both of the form of the ocean floor and the 

 deposits that cover it. 



It is not the purpose of the present essay to consider the origin or 

 the age of the great oceanic basins — whether they are primitive and 

 original planetary features, or whether they have arisen by differen- 

 tial subsidence of parts of the earth crust or are "gapes" left by the 

 drifting apart of the continents. These questions have been dis- 

 cussed almost ad nauseam during the past two decades: suffice it to 

 say that the consensus of geological opinion does not favor the Wege- 

 ner hypothesis of continental drift, although admitting the possi- 

 bility that such drift may occur in certain parts of the crust on a 



1 Reprinted by permission from Science Progress, vol. 32, No. 125, July 1937. 



275 

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