166 FORESTRY OF NORWAY. 



pressure every air-bubble had been expelled, and the 

 whole mass was clear and transparent ; the cavern appeared 

 like a tunnel cut through a mountain of sapphire. Un- 

 fortunately I could not explore it on account of the great 

 depth and velocity of the water, as it ran between two 

 stone ridges, split by the ice. The retiring glacier had 

 uncovered part of a spur or hill of gneiss, which had ob- 

 structed its march, and which was split into several enor- 

 mous parts, which were still in contact with each other. 

 A considerable number of boulders were resting on the 

 frozen mass, some supported on pillars of ice, which were 

 prevented from melting by the protecting shade of the 

 stones. In places the glacier was white, not from snow, 

 but in consequence of the cracking of its surface and 

 numerous air-cells. It was easy to see that the Lodal had 

 formerly been much lower down the valley, and that the 

 transverse glaciers we had met on the way were once its 

 lateral branches, the whole forming a single vast frozen 

 river reaching the sea, retiring, advancing, again retiring. 

 Thus the ice ground deeper and deeper into the rocks ; the 

 same marks were visible, left by that which had retired 

 the year before. I heard a rumbling sound, and had hardly 

 raised my eyes when a huge stone from the glacier rolled 

 within a few feet of me ; and I had hardly seated myself 

 the second time when I saw another stone roll down car- 

 rying with it in its flight several lesser ones/ 



M. du Chaillu goes on to say: 'A glacier is not an 

 immovable mass closely attached to the mountains, but a 

 body slowly impelled forward by the immense pressure of 

 the upper portions. On its way the mass slides down 

 grinding its rocky bed, thus deepening and enlarging its 

 channel, day by day; its silent power, overcoming all 

 obstacles, carries with it whatever has been buried in the 

 icy stream, such as stones that have fallen from the moun- 

 tain sides, earth, and sand, which combine to render the 

 water turbid, and to form the moraines. It has the charac- 

 ter of a stream ; it is a moving river of ice fed from the 

 sneebraer or perpetual snow-fields above, modifying or creat- 



