392 THE NORTH POLAR BASIN. 



the half-melted snow frozen on the surface. But it was too late; there 

 were many large patches of dark ground which rapidly absorbed the 

 sun's heat, the snow melted under the frozen crust, and its final col- 

 lapse was as rapid as it was complete. 



In the basin of the Yenisei the average thickness of the snow at the 

 end of winter is about 5 feet. The sudden transformation of this 

 immense continent of snow, which lies as gently on the earth as an 

 cider-down quilt upon a bed, into an ocean of water rushing madly 

 down to the sea, tearing everything up that comes into its way, is a 

 gigantic display of power, compared with which an earthquake sinks 

 into insignificance. It is difficult to imaguie the chaos of water which 

 must have deluged the country before the river beds were worn wide 

 enough and deep enough to carry the water away as quickly as is the 

 case now. If we take the Lower Yenisei as an example, it maybe i^os- 

 sible to form some conception of the work which has already been done. 

 At Y^eniseisk the channel is about a mile wide; 800 miles lower down 

 (measuring the windings of the river), at the village of Kureika, it is 

 about 3 miles wide; and following the mighty stream for about another 

 800 miles down to the Brekofisky Islands, it is nearly G miles wide. 

 Tlie depth of the channel varies from 50 to 100 feet above the winter 

 level of the ice. This ice is about 3 feet thick, covered with 6 feet of 

 snow, which becomes flooded shortly before the break-up and con- 

 verted into about 3 feet of ice, white as marble, which lies above the 

 winter blue ice. When the final crash comes, this field of thick ice is 

 shattered like glass. The irresistible force of the flood behind tears 

 it up at an average rate of 4 miles an hour, or about 100 miles a day, 

 and drives it down to the sea in the form of ice floes aiul pack ice. 

 Occasionally a narrow part of the channel or a sharp bend of the river 

 causes a temporary check; but the pressure from behind is irresistible, 

 the pack ice is piled into heaps, and the ice floes are doubled up into 

 little mountains, which rapidly freeze together into icebergs, which float 

 ott' the banks as the water rises. Meanwhile, other ice floes come up 

 behind; some are driven into the forests, where the largest trees are 

 mown down by them like grass, whilst others press on until the barrier 

 gives way and the waters, suddenly let loose, rush along at double 

 speed, carrying the icebergs with theui with irresistible force, the 

 pent-up dam which has accumulated in the rear often covering hun- 

 dreds of square miles. In very little more than a week the ice on the 

 800 miles, from Y^eniseisk to the Kureika, is completely broken uj), and 

 in little more than another week the second 800 miles, from the Kureika 

 to the Brekoflsky Islands, is in the same condition. 



During the glacial epoch the annual fight between winter and the 

 sun nearly always ended in the victory of the former. Even now the 

 fight is a very desperate one within the Polar Circle and is subject to 

 much geograi)hical variation. The sun alone has little or no chance. 

 The armies of winter are clad in white armor, absolutely proof agaiust 



