AQUEOUS AGENCIES. 



59 



body, all together, sliding on its bed, but exactly like a 

 stiffly viscous body. In other words, the motion of a 



FIG. 29. Mer de Glace, with its tributaries and its moraines. 



glacier is a current-motion. Like a river, it not only 

 slides on its bed, but also the different parts move with 



