242 ACCOUNT OF THE ATICTIC REGIONS. 



a hundred miles. The ice of which they are com- 

 posed, is generally pure and fresh ; and in heavy 

 fields, it is prohiibly of the average thickness of ten 

 to fifteen feet, and 'then appears to be flat, low, thin 

 ice ; but where high hummocks occur, the thickness 

 is often forty, or even fifty feet. The surface before 

 the month of July, is always covered with a bed of 

 snow, of perhaps a foot to a fathom in depth ; this 

 snow dissolves in the end of summer, and forms ex- 

 tensive pools and lakes of fresh water. Some of the 

 largest fields are very level and smooth, though ge- 

 nerally their surfaces are varied with hummocks. 

 In som?, these hummocks form ridges or chains, in 

 others, they consist of insulated peaks. I once saw 

 a field that was so free from either fissure or hum- 

 mock, that I imagine, had it been free from snow, 

 a coach might have been driven many leagues over 

 it in a direct line, without obstruction or danger. 

 Hummocks somewhat relieve the uniformity of in- 

 tense light reflected from the surface of fields, by ex- 

 hibiting shades of delicate blue in all the hollows, 

 where the light is partly intercepted by passing 

 through a portion of ice. When the surface of the 

 snow on fields is frozen, or when the snow is gener- 

 ally dissolved, there is no difiiculty in travelling 

 over them, even without either snow skaits or sledges ; 

 but when the snow is soft and deep, travelling on 

 foot to any distance, is a work of labour. The tribe 

 of Esquimaux discovered by Captain Ross, made 



