268 ANNUAL OF SCIENTIFIC DISCOVERY. 



land on either side, would be neither sufficiently wide nor deep to 

 form a considerable outlet. Under such circumstances, it would 

 scarcely seem more necessary that the gulf stream should hold its 

 original north-westerly course over the submerged continent of Amer- 

 ica, than that it should complete its circuit by passing through the 

 Arctic Sea, and returning to the Atlantic across the submerged land 

 of Europe, as it now completes a more circumscribed circuit by being 

 constrained to pass along the northern portion of the Atlantic itself. 



The effect of this diversion of the gulf stream from its present 

 course, would not be less remarkable in elevating the temperature of 

 the northern shores of America and Asia, than in reducing that of 

 western Europe. It can be shown that the mean annual temperature 

 of Iceland is increased 18 or 20 Fahr., and the January tempera- 

 ture 34, by the influence of this important current. There can be 

 no reasonable doubt, therefore, of its raising the temperature of the 

 north-western coast of America, from the Mackenzie river to Behr- 

 ing's Straits, by an amount at least equal to that by which it now ele- 

 vates the temperature of Iceland. Further, it is highly probable that 

 the principal course of the current in the Arctic Sea would not be 

 far from the coasts of northern Asia, the temperature of which would 

 thus be affected in a manner similar to that of the coast of America 

 eastward of Behring's Straits. The temperature of winter immedi- 

 ately east of the Ural Mountains, would also be considerably moder- 

 ated, as already stated, by the extension of the European sea towards 

 their western flanks. The climate of the low lands of northern Asia 

 would thus differ from the present climate of that region, as much as 

 the existing climate of the western coast of Norway differs from that 

 which would desolate that region in the absence of the gulf stream. 



According to this view of the subject, the former existence in 

 northern Asia of the immense numbers of large Mammalia indicated 

 by the abundance of their fossil remains, no longer presents the 

 slightest difficulty ; and the theory receives a still further confirmation 

 from an observation made by Sir John Ilichardson in his "Arctic 

 Searching Expedition," just published. The author observes, "The 

 existence of these numerous testimonials of an ancient fauna is sug- 

 gestive of many curious speculations, and geologists seem hitherto to 

 have failed in explaining the circumstances under which accumula- 

 tions so vast could occur in such high latitudes. The difficulty is 

 increased when we consider that these bones have not been detected 

 to the east of the Rocky Mountains in high latitudes." This increased 

 difficulty, however, is at once removed by the theory now proposed, 

 for the region in which these remains are not found, must either have 

 been covered with the waters of the ocean to the foot of the Rocky 

 Mountains at the period when these Mammalia occupied the region to 

 the westward, or if land existed on the north-east of the present 

 American continent, it was probably too cold to be inhabited by them. 

 Their disappearance from the country bounding the Arctic Sea, from 

 the Rocky Mountains to the Ural, would be the consequence of the 

 withdrawal of the gulf stream from the more eastern, and of the Euro- 



