2Q2 SOME OF THE SCIENTIFIC ASPECTS OF SNOW. 



raise a stratum of air, 800 feet thick, from freezing point to 

 the tropical heat of 88 Fahr." * 



Masses of heavy snow therefore are possessed of 

 great immobility, and melt but slowly under the action 

 of sunshine in consequence of their great power of 

 reflecting heat, and so dispersing it into the atmo- 

 sphere; so much so, that even in Great Britain, after 

 winters when the snowfall has been exceptionally 

 heavy, and drifts of considerable depth have formed 

 in sheltered places, among hills, unmelted patches of 

 snow are sometimes visible well on into the spring. 

 This permanent storing up of cold in the form of 

 snow is therefore capable, under certain circumstances, 

 of producing extraordinary effects in the physical 

 geography and climate of countries, as is at present 

 exemplified in the constantly snow-covered condition 

 of Greenland and of South Georgia and Sandwich 

 Island in the South Pacific; while other places con- 

 siderably nearer to the pole possess a vegetation of 

 comparative and even extreme luxuriance, though their 

 summers are necessarily shorter, and also the cold of 

 the winters probably more intense. The permanent 

 storing up of cold therefore, Mr. Wallace has pointed 

 out, 



" depends entirely on the annual amount of snowfall in 

 proportion to heat, and not on the actual cold of the winter, 

 or even the average cold of the year. A place may be in- 

 tensely cold in winter, yet if little snow falls there is nothing 

 to prevent the summer being hot, and the earth producing 

 luxurious vegetation." f 



There are however some northern countries where 



* Island Life or Insidar Faunas and Floras and Geological Climates^ 

 by Alfred R. Wallace, 1880, p. 30. 

 f Ibid., p. 30. 





