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HKLMHOLTZ 



in its crevices, they fall, and for the most part on the edge 

 of the mass of ice. There they either remain lying on the 

 surface, or if they have originally burrowed in the snow, 

 they ultimately reappear in consequence of the melting of 



FIG. in 



the superficial layers of ice and snow, and they accumulate 

 especially at the lower end of the glacier, where more of 

 the ice between them has been melted. The blocks which are 

 gradually borne down to the lower end of the glacier are 

 sometimes quite colossal in size. Solid rocky masses of this 

 kind are met with in the lateral and terminal moraines, 

 which are as large as a two-storied house. 



The masses of stone move in lines which are always nearly 

 parallel to each other and to the longitudinal direction of 

 the glacier. Those, therefore, that are already in the middle 

 remain in the middle, and those that lie on the edge remain 

 at the edge. These latter are the more numerous, for during 

 the entire course of the glacier fresh boulders are constantly 

 falling on the edge, but cannot fall on the middle. Thus are 

 formed on the edge of the mass of ice the lateral moraines, 



