354 BOUNDARIES OF THE POLAR BASIN. 



the rivers which flow northward. He will observe 

 that the long line of coast which gives lodgment to 

 these Arctic nomads is interrupted in three principal 

 places; and that through these the waters of the 

 Polar Sea mingle with the waters of the Atlantic 

 and Pacific Oceans, — these breaks being Baffin Bay, 

 Behring Strait, and the broader opening between 

 Greenland and Nova Zembla; and if he traces the 

 currents on the map and follows the Gulf Stream as 

 it flows northward, pouring the warm waters of the 

 Tropic Zone through the broad gateway east of Spitz- 

 bergen and forcing out a return current of cold waters 

 to the west of Spitzbergen and through Davis Strait, 

 he will very readily comprehend why in this incessant 

 displacement of the waters of the Pole by the waters 

 of the Equator the great body of the former is never 

 chilled to within several degrees of the freezing-point ; 

 and since it is probably as deep, as it is almost as 

 broad, as the Atlantic between Europe and America, 

 he will be prepared to understand that this vast 

 body of water tempers the whole region with a 

 warmth above that which is otherwise natural to it ; 

 and that the Almighty hand, in the all-wise dispensa- 

 tion of His power, has thus placed a bar to its conge- 

 lation ; and he will read in this another symbol of 

 Nature's great law of circulation, which, giving water 

 to the parched earth and moisture to the air, moderates 

 as well the temperature of the zones — cooling the 

 Tropic with a current of water from the Frigid, and 

 warming the Frigid with a current from the Tropic.^ 



1 The temperature of the air at the North Pole has furnished a fruitful 

 theme of speculation, both in connection with the influence of the sea and 

 of the sun. I have before me a highly instructive paper on the climate of 

 the North Pole, read before the Royal Geographical Society of London, 



