42 SPARKS FROM A GEOLOGIST'S HAMMER. 



Well, the glacier is under our feet at length. It is 

 the Mer de Glace. We read of this wonder of nature 

 when we were boj'S in school, and puzzled over the poor 

 uninterpretable pictures of it in our text-books. It is 

 not so roucfh and rent with fractures as we had thougrht. 

 The path winds over its wave-like swells and around its 

 yawning crevasses; and we march on, thinking of the 

 depth of the river of ice on which we walk; of its slug- 

 gish, crawling movement down toward the valley of 

 Charaonix; of the years which have rolled by since the 

 ice under our feet was fresh-fallen snow on Mont Man- 

 dit; of the terrific winter storms which howled about 

 the cradle of the glacier; of the deliberateness of all of 

 Nature's operations. And then we reflect how all this 

 work was going on before we were in existence; and 

 how, when we shall have ceased to appear among men. 

 Nature's operations will experience no check, but con- 

 tinue to move on in their appointed ways, steadily, pa- 

 tiently, while other generations of men may come and 

 go. Here, far from the glacier's border, are fragments 

 of rocks riding in state upon the glacier's back, down 

 from the region of some high alpine cliff, toward the 

 precincts of human habitation. These, like the boulders 

 of the border, are formed of that peculiar species of rock 

 which constitutes the core of the Alpine chain. Here, 

 now, are those crevasses which create so much of the 

 peril of glacier adventure. The crevasse is a fissure in 

 the mass of ice. Its direction on the surface is gener- 

 ally transverse to the axis of the glacier, or approxi- 

 mately so. In length it may vary from twenty feet to a 

 mile. Its downward direction is originally vertical; but 

 as the surface of the glacier moves more rapidly than 



