ICE AND GLACIERS. 105 



border as far as we can see from the river, and then the united 

 currents stretching downwards to beyond Asmannshausen and 

 Burg Rheinstein ; such a current would also about correspond 

 to the size of the Mer de Glace. 



Fig. 16, which is a view of the magnificent Gorner Glacier 

 seen from below, also gives an idea of the size of the masses of 

 ice of the larger glaciers. 



FIG. 16. 



The surface of most glaciers is dirty, from the numerous 

 pebbles and sand which lie upon it, and which are heaped together 

 the more the ice under them and among them melts away. The ice 

 of the surface has been partially destroyed and rendered crumbly. 

 In the depths of the crevasses ice is seen of a purity and clear- 

 ness with which nothing that we are acquainted with on the 

 plains can be compared. From its purity it shows a splendid 

 blue, like that of the sky, only with a greenish hue. Crevasses 



