204 GLACIERS. 



love to pour out my soul burdened with ecstacy al the bare remem- 

 brance of this awfully sublime spectacle. 



" A world of wonders, where creation seems 

 No more the works of nature, but her dreams. " 



Glaciers are masses of ice, encased in the valleys or suspended by 

 the flanks of lofty mountains. Their extent is, of course, various. — 

 Those, which occupy the valleys of the Alps, descend, in general, from 

 the highest summits and extesnd down to the regions of cultivation. — 

 These are glaciers from 16 to 18 miles long, and even more, and from 

 1 to 3 miles wide. 



They owe their existence to the eternal snow. When this increases 

 to an enormous extent in the high mountains, and moves down in over- 

 whelming masses to regions where it partly thaws and freezes again, 

 and thus increases from year to year, a glacier is formed. The solid 

 mass moves on, while it accumulates in the rear, and thus gradually des- 

 cends to the bottom of the valley. There the end of it is melted away 

 but it is still increasing behind, so that from age to age, it presents the 

 same unchanging appearance. The water of rains and the melted snow 

 ■penetrate the interior, where they freeze, and thus the huge mass is 

 held together. This is the transition from snow to ice. The freezing 

 process is going on even during the nights of summer, and already at 

 sun-down, however hot the day may have been, the cold is intense. 



Glacier ice has peculiar properties. The volume of water absorbed 

 by glaciers is very unequal. It is greatest, of course, when the rays of 

 the sun act most directly. On account of this unequal distribution of 

 water, and from the fact that it does not freeze instantaneously, the ice 

 is not of equal character, like that which the cold of winter produces 

 on rivers. In the upper strata, (for glaciers are strata of ice,) the ice is 

 composed of irregular pieces of various size and of various angles. — 

 Some are nearly round — others angular. They are not always united 

 together, but the larger the pieces, the less the cohesion. Wind, rain 

 and heat make the ice porous, and render it capable of being bored. — 

 Agassiz had occasion to bore it frequently to carry on his observations. 

 He found it of unequal solidity, and discovered the softening effect of 

 the atmosphere upon it. At one expeiiment, he bored only half a foot 

 after several hours work, but on the following day, after a heavy rain, 

 he penetrated a foot in half an hour. 



The color of the ice is various : sometimes it is white and from a 

 distance it looks like marble, the larger pieces are pale green, sometimes, 

 there is a bluish reflection, and sometimes, rose red. Occasionally the 



