26 Change in the Ear Ms Superficial Jemperature. 



it now elevates 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, although in a 

 smaller degree for greater distances on the west of the Straits. The 

 temperature of winter immediately east of the Ural Mountains 

 would also be considerably moderated, 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 de- 

 solate 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 indi- 

 cated 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 Richardson 

 in his " Arctic Searching Expedition," * just published. The 

 author observes — "The existence of these numerous testimonials 

 of an ancient fauna is suggestive of many curious speculations, 

 and geologists seem hitherto to have failed in explaining the cir- 

 cumstances under which accumulations 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 conse- 

 quence of the withdrawal of the Gulf Stream from the more 

 eastern, and of the European ocean from the more westerly portion 

 of that region. Fossil plants, also, belonging to a comparatively 

 warm climate, have been found east of the Rocky Mountains, on 

 the coast of the North Sea ; and extensive beds of lignite exist 

 along the eastern flank of those mountains. So far as these 

 phenomena may be of pleistocene origin, they may be at once 

 accounted for by this theory. Its more complete verification 

 must, however, be left to future observation. It will not fail, I 

 hope, to attract the attention of American geologists. 



* Vol. ii., p. 210. 



