ALPINE SCULPTURE 253 



mission of dislocations. I never met with a precise state- 

 ment of the manner in which the advocates of the fissure 

 theory suppose the forces to have acted whether they as- 

 sume a general elevation of the region, or a local elevation 

 of distinct ridges; or whether they assume local subsidences 

 after a general elevation, or whether they would superpose 

 upon the general upheaval minor and local upheavals. 



In the absence of any distinct statement, I will assume 

 the elevation to be general that a swelling out of the 

 earth's crust occurred here, sufficient to place the most 

 prominent portions of the protuberance three miles above 

 the sea- level. To fix the ideas, let us consider a circular 

 portion of the crust, say one hundred miles in diameter, 

 and let us suppose, in the first instance, the circumference 

 of this circle to remain fixed, and that the elevation was 

 confined to the space within it. The upheaval would throw 

 the crust into a state of strain; and, if it were inflexible, 

 the strain must be relieved by fracture. Crevasses would 

 thus intersect the crust. Let us now inquire what propor- 

 tion the area of these open fissures is likely to bear to the 

 area of the unfissured crust. An approximate answer i 

 all that is here required; for the problem is of such a 

 character as to render minute precision unnecessary. 



No one, I think, would affirm that the area of the fis- 

 sures would be one- hundredth the area of the land. For 

 let us consider the strain upon a single line drawn over 

 the summit of the protuberance from a point on its rim 

 to a point opposite. Kegarding the protuberance as a 

 spherical swelling, the length of the arc corresponding to 

 a chord of 100 miles and a versed sine of 3 miles is 100-24 

 miles; consequently, the surface to reach its new position 

 must stretch 0-24 of a mile, or be broken. A fissure or a 





