54 



SPARKS FROM A GEOLOGIST'S HAMMER. 



Lateral Zones are much less tilted, and seem to have been 

 displaced by the up-thrust of the Middle Zone. All the 

 rocks which we have observed belong to the Middle Zone; 

 but in this zone is a huge central mass of unstratified Al- 

 pine granite, or protogine, constituting the loftiest summits 

 of the chain, Mont Blanc, Monte Rosa, Bernina, Jung- 

 frau, Finsteraarhorn, and others. while the contiguous 

 portion?, on either hand, consist of masses of vertically 

 stratified schists, as we have seen in Aiguille de Char- 



MONT BLANC 



AIGUILLES Roacrs 



a, Protogine 



a', Crystalline Schists 



b, Anthracilic Schists 



c , \crrueano 



SluJer: Geot 



c', Feldspatluc Schists 

 d, Dolon.it, c Limestone 

 e, Black Limestone and Schists 

 r, Gvpsum 

 ee cter- ScAneie 



STRUCTURE OF THE ALPS OF CENTRAL EUROPE. 



moz, Aiguille du Dru and othsr pinnacles.* By weath- 

 ering, these projecting strata assume the castellated forms 

 so magnificently displayed from the Flegere. The un- 

 stratified protogine, on the contrary, weathers into the 

 class of rounded forms of which Mont Blanc is the type. 

 It is from the loftier " central mass" that the boulders 

 of protogine so abundant along the paths of the glaciers 

 have been transported. 



* Stnder, Geo'ogif fler Schirclz. 



