XIV.] THE GEOLOGY OF THE ALPS. 337 



The existence of great and perplexing inversions of strata in 

 many parts of the Alps is well known. One of the most strik- 

 ing cases is that figured by Murchison in his remarkable paper 

 on the geology of the Alps in 1848 (Quar. Jour. Geol. Soc., V. 

 246), as occurring at the pass of Martinsloch in the canton of 

 Glarus, 8,000 feet above the sea. Here nummulitic beds, dip- 

 ping S. S. E. at a high angle, are regurlaly overlaid by the 

 succeeding sandstone (flysch), resting unconformably and in a 

 nearly horizontal attitude upon the edges of which are 150 feet 

 of hard Jurassic limestone, overlaid in its turn by talcose and 

 micaceous schists, which are by Escher regarded as similar to 

 those which underlie these limestones in the valley below. 

 This mass of flysch appears near by to dip beneath these lime- 

 stones, which, in their turn, are regularly overlaid by neocomian 

 and cretaceous strata. This remarkable superposition of sec- 

 ondary and older crystalline rocks to tertiary is explained by 

 Murchison, in accordance with the suggestion of H. D. Rogers, 

 as the probable result of fracture and displacement along an 

 anticlinal. Many striking examples of inversion are described 

 by Favre in the vicinity of Mont Blanc. The mountain of the 

 Voirons, near Geneva, shows at its base tertiary overlaid by 

 cretaceous rocks, upon which Jurassic strata are superimposed. 

 Similar phenomena are met with along the north side of the 

 Alps from Geneva to Austria, and at various localities on the 

 southern side, in Lombardy. This inversion, moreover, is by 

 no means confined to secondary and tertiary strata. In the val- 

 ley of Chamonix the secondary limestones dip at a high angle 

 toward Mont Blanc, and plunge beneath its crystalline schists. 

 Other examples of the superposition of crystalline schists to the 

 fossiliferous sediments have been pointed out by Elie de Beau- 

 moiit in the mountains of Oisans, and confirmed by Lory and 

 Dausse, while similar cases have been recognized by Morlot 

 and Yon Hauer in the eastern Alps, and by Ramond, De Bouche- 

 porn, and others in the Pyrenees. All of these cases are by 

 Favre regarded as examples of the same process of inversion 

 already noticed in so many instances among the secondary and 

 tertiary strata of the region. He proceeds to contrast these 

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