82 THE ICE AGE IN CANADA. 



inHnencc of gravity." (Trotter, in I'roc. lioyal Society of 

 London, XXXA'] I i., 107.) 



AVoeickolfs conclusions may lie suninied u]) as follows: 



"1. The great expanse of ocean in the southern hemis- 

 phere is fa\ourable to the cle})osit of snow and f(jrmation 

 of glaciers, hy furnishing a great evaporating surface, and 

 at the same time a low general tem})erature facilitating 

 lirecipitation. This a])])lies to the antarctic continent, 

 and also permits the formation of glaciers far to the north 

 in Xew Zealand and in South America. 



"2. On the other hand, the i)resent condition of the 

 northern hemisphere is unfavoural)le to glaciers, Itecause 

 the sea is so warm that deposition near the coasts is 

 rather as rain than snow up to pretty high latitudes, 

 while the continents are so wide that there is little 

 precipitation in their interior. 



"3. Thus there are no glaciers in eastern Silieria, even 

 in the mountains, where the mean ten)peratnre is only 15" 

 to 16° C, and central Asia generallv is inifav(niral)le to 

 glaciation on accoinit of its dryness, while eastern Asia is 

 acted on 1)V the monsoons. If, therefore, the extent of 

 land in Asia has not materially changed since the riiocene 

 ])eriod, there could not have heen great glaciers there 

 since that period. Even the submergence of the great 

 ])lain of China could not materially aflect this result, 

 though it might cause glaciers in the mountains of 

 Japan. 



"4. To ex])lain the great I'leistocene glaciers, of which 

 traces are found in western Europe, it is necessary to 

 suppose that the temi)erature was lower, either on account 

 of submergence of the low lands or of diversion of warm 

 currents, or both causes may have operated. A submer- 

 gence connecting the White and Baltic .seas would greatly 



