292 THE BEAUTIES OF NATURE chap. 



somewliat curved line from the Maritime Alps, 

 commencing with the islands of Hyeres, by 

 Briancon, Martigny, the Valais, Urseren Thai, 

 Voider Rhein, Innsbruck, Radstadt, and 

 Rottenmann to the Danube, a little below 

 Vienna, — at first nearly north and south, but 

 gradually curving round until it becomes 

 S.W. by N.E; 



The central mountains are mainly composed 

 of Gneiss, Granite, and crystalline Schists : 

 the line of junction between these rocks and 

 the secondary and tertiary strata on the north, 

 runs, speaking roughly, from Hyeres to Gre- 

 noble, and then by Albertville, Sion, Chuv, Inns, 

 brack, Radstadt, and Hieflau, towards Vienna. 

 It is followed (in some part of their course) 

 by the Isere, the Rhone, the Rhine, the Inn, 

 and the Enns. One of the great folds shortly 

 described in the preceding chapter runs up 

 the Isere, along the Chamouni Valley, up the 

 Rhone, through the Urseren Thai, down the 

 Rhine Valley to Chur, along the Inn nearly to 

 Kuf stein, and for some distance along the 

 Enns. Thus, then, five great rivers have 

 taken advantage of this main fold, each of 



