THE GLACIAL PERIOD AND THE EARTH-MOVEMENT HYPOTHESIS. 223 



the Pleistocene period were simply an exaggeration of those 

 now existing. The great inland-ice of Northern Europe is 

 represented to-day by the snow-fields and glaciers of Norway, 

 while the glaciers of the Alps and other mountain-regions are 

 the descendants of those of Pleistocene times. During the 

 glacial period precipitation and accumulation of snow 

 diminished from west to east, and the same is the case at 

 present, for the snow-fields and glaciers of the Western Alps 

 are on a larger scale than those that appear in the eastern 

 portion of the chain. Again, while Norway has its glaciers, 

 in the Urals there is none. Even during the climax of the 

 glacial period the Ural Mountains nourished only a few small 

 local glaciers. We note further that mountains which hi our 

 day do not reach the snow-line supported in glacial times 

 relatively small snow-fields and glaciers. The contempor- 

 aneous phenomena of North America tell a similar tale. The 

 north-eastern section of that continent was mantled with an 

 immense ice-sheet, while in the far west only gigantic local 

 glaciers existed. To-day the same contrast presents itself; 

 in the north-east we have Greenland drowned in ice, but the 

 loftier mountain-regions of the far North- West, although lying 

 in the same latitude, support only local ice-flows. Were the 

 climatic conditions of the glacial period to return, ice-sheets 

 and glaciers would again extend over the same areas formerly 

 occupied by them. This marked accord between the physical 

 conditions of the Ice Age and those of the present, so far as the 

 ratio of precipitation is concerned, cannot be too strongly 

 emphasized. The old snow-fields, mers de glace, and local 

 glaciers accumulated within those areas of northern and 

 temperate latitudes where now-a-days snow and rain are 

 precipitated most copiously ; while traces of glaciation are 

 either wholly wanting or very meagrely present in those 

 northern and temperate latitudes which are even now notable 

 for their dryness. It is needless to say that any theory that 

 attempts to account for the glacial climate has these salient 

 facts to reckon with. 



The question of the origin of that climate has been greatly 

 complicated by the rapidly increasing evidence which proves 

 that the Ice Age was interrupted by one or more stages 

 during which temperate conditions prevailed. So long as 

 geologists had only one glacial epoch to account for they had 

 less difficulty in suggesting feasible explanations. It was hard 

 or even impossible, however, to reconcile such explanations 

 with the occurrence of interglacial deposits, One is not sur- 



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