44 SPARKS FROM A GEOLOGIST'S HAMMER. 



sage of the Mer de Glace; but with it comes the exhila- 

 ration and the determination to accomplish the transit 

 without a guide. If worst comes, there is a man hang- 

 ing upon our heels, expecting that the next moment will- 

 find us suing for his assistance. The peril arises from 

 the absence of any discernible path, and our ignorance 

 of the route indicated as easiest by the continued ex* 

 perience of the guides. 



DIFFICULT PASSAGE ON THE MEK DE GLACE. FROM A PHOTO- 

 GRAPH BY J. LEVY ET CIE., PARIS. 



The farther border is reached in safety, if there be 

 any border-line between the ice and the earth into 

 which it graduates by insensible degrees. Another con- 

 test with huge boulders of protogine, and we strike a 



