THE CONTINENTAL GLACIERS OF POLAR REGIONS 283 



which exact measurements indicate to be but one foot per day, and 

 at a distance of a mile and a quarter from the margin even this 

 slight value has diminished by fully one eighth. It can hardly 

 be doubted that at moderate distances only within the ice margin, 

 the glacier is practically without motion. 



Rain or general melting conditions being unknown in Antarctica, 

 a striking contrast is offered to the marginal zone of the Greenland 

 continent. This is to a large extent explained by the existence 



Great Ice Barrier 



'Ut722r* Long.15S16' 



Vtniai Scale of rest 



FIG. 311. Sections across the inland ice of Victoria Land, Antarctica, with the 

 shelf ice in front (after Shackleton) . 



upon the northern land mass of a coast-land ribbon which becomes 

 quickly heated in the sun's rays, and both by warming the air and 

 by radiating heat to the ice it causes melting and produces local 

 air temperatures which in summer may even be described as hot. 

 About Independence Bay in latitude 82 N. and near the north- 

 ernmost extremity of Greenland, Peary descended from the in- 

 land ice into a little valley within which musk oxen were lazily 

 grazing and where bees buzzed from blossom to blossom over a 

 gorgeous carpet of flowers. 



Nourishment of continental glaciers. Explorations upon and 

 about the glaciers of Greenland and Antarctica have shown that 

 the circulation of air above these vast ice shields conforms to a 

 quite simple and symmetrical model subject to spasmodic pulsa- 



