296 LOUIS AGASSIZ. 



needles^ tables, perched blocks, gravel cones, 

 rifts, and crevasses, as well as their movements, 

 mode of formation, and internal temperature, 

 were treated in succession. But the most in- 

 teresting chapters, from the author's own 

 point of view, and those which were most 

 novel for his readers, were the concluding 

 ones upon the ancient extension of the Swiss 

 glaciers, and upon the former existence of an 

 immense, unbroken sheet of ice, which had 

 once covered the whole northern hemisphere. 

 No one before had drawn such vast conclu- 

 sions from the local phenomena of the Alpine 

 valleys. " The surface of Europe,'' says Agas- 

 siz, " adorned before by a tropical vegetation 

 and inhabited by troops of large elephants, 

 enormous hippopotami, and gigantic carniv- 

 ora, was suddenly buried under a vast mantle 

 of ice, covering alike plains, lakes, seas and 

 plateaus. Upon the life and movement of 

 a powerful creation fell the silence of death. 

 Springs paused, rivers ceased to flow, the rays 

 of the sun, rising upon this frozen shore (if, 

 indeed, it was reached by them), were met 

 only by the breath of the winter from the 

 north and the thunders of the crevasses as 

 they opened across the surface of this icy 

 sea." ^ The author goes on to state that on 



1 J^tudes sur les Glaciers. Chapter xviii. p. 315. 



