THE PHYSICAL CONDITION OF THE OCEAN.i 



By Capt. W. J. L. Wharton, R. N., F. R. S. 



You will not be surprised if, having called upon an liydrograpber to 

 preside over this section, he takes for the subject of his review the sea. 

 Less apparently interesting, by reason of the uniformity of its surface, 

 than the land which raises itself above the level of the waters, and 

 with which the term geography is more generally associated, the ocean 

 has, nevertheless, received much attention of later years. In Great 

 Britain, especially, which has so long rested its i)Osition among the 

 nations upon the wealth which our merchant tieets bring to its shores, 

 and upon the facilities which the sea affords for communication with 

 our numerous possessions all over the globe, investigation into the 

 mysteries, whether of its ever-moving surface or of its more hidden 

 depths, has been particularly fascinating. I purpose, therefore, to 

 attempt a brief survey of our present knowledge of its physical 

 condition. 



The very bulk of the ocean, as compared with that of the visible laud, 

 gives it an importance which is possessed by no other feature on the 

 surface of our planet. Mr. John Murray, after a laborious computation, 

 has shown that its cubical extent is probably about fourteen times that 

 of the dry land. This statement appeals strongly to the imagination, 

 and forms, perhaps, the most powerful argument in favor of the view, 

 steadily gaining ground, that the great oceans have in the main existed 

 in the form in which we now see them since the constituents of the 

 earth settled down into their present condition. 



When it is considered that the whole of the dry land would only fill 

 i\]) one third of the Atlantic Ocean, the enormous disproportion of the 

 two great divisions of land and sea becomes very apparent. 



The most obvious phenomenon of the ocean is the constant horizontal 

 movement of its surface waters, which in many i)arts take well-defined 

 directions. These great ocean currents have now been studied for 



' Address to the geographical section of the British Association, Oxford, 1894. Puh- 

 lished by the British Association, also printed in the Geographical Journal, Septem- 

 ber, 1894, and in Nature, August 16, 1894. 



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