TEE " GREAT ICE AGE." 119 



their gigantic predecessors ; those of the southern slope of 

 the Alps are doing a large share in filling up the Adriatic ; 

 while the chips of all merely rest upon the glacier beds 

 forming the comparatively insignificant terminal moraine 

 deposits. 



The same in Scandinavia. The Storelv of the Jostedal 

 is fed by the melting of the Krondal, Nygaard, Bjornestegs, 

 and soldal glaciers. It has filled up a branch of the deep 

 Sogne fjord, forming an extensive fertile plain at the mouth 

 of its wild valley, and is depositing another subaqueous 

 plain beyond, while the moraines of the glaciers are but in- 

 considerable and comparatively insignificant heaps of loose 

 boulders, spread out on the present and former shores of the 

 above-named glaciers, which are overflows from one side of 

 the great neve, the Jostedal Sneefond. All of these glaciers 

 flow down small lateral valleys, spread out, and disappear 

 in the main valley, which has now no glacier of its own, 

 though it was formerly glaciated throughout. 



What must have been the condition of this and the other 

 great Scandinavian valleys when such was the case ? To 

 answer this question rationally we must consider the meteoro- 

 logical conditions of that period. Either the climate must 

 have been much colder, or the amount of precipitation 

 vastly greater than at present, in order to produce the gene- 

 ral glaciation that rounded the mountains up to a height of 

 some thousands of feet above the present sea-level. Probably 

 both factors co-operated to effect this vast glaciation, the 

 climate colder, and the snow-fall also greater. The whole 

 of Scandinavia, or as much as then stood above the sea, 

 must have been a neve or sueefond on which the annual 

 snow-fall exceeded the annual thaw. 



This is the case at present on the largest neve of Europe, 

 the 500 square miles of the great plateau of the Jostedals 

 and Nordf jords Sneefond, on all the overflowing neve or 

 snow-fields of the Alps above the snow -line; over the greater 

 part of Greenland; and (as the structure of the southern 

 icebergs prove) everywhere within the great Antarctic ice 

 barrier. 



What, then, must happen when the snow-line comes 

 down, or nearly down, to the sea-level ? It is evident that 



