172 THE PHYSICAL GEOGRAPHY OF THE SEA. 



472. I may here remark, that there seems to be a larger flow 

 of polar waters into the Atlantic than of other waters from it, and 

 I can not account for the preservation of the equilibrium of this 

 ocean by any other hypothesis than that which calls in the aid of 

 under currents. They, I have no doubt, bear an important part 

 in the system of oceanic circulation.^' 



* See Addenda. 



