. vI MOUNTAINS 223 
Appenzell, and Bregenz on the Lake of Con- 
stance, is the lowland occupied by later 
Tertiary strata; between this second line 
and another passing through Albertville, St. 
Maurice, Lenk, Meiringen, and Altdorf lies a 
more or less broken band of older Tertiary 
strata; south of which are a Cretaceous zone, 
one of Jurassic age, then a band of crystalline 
rocks, while the central core, so to say, of the 
Alps, as for instance at St. Gotthard, consists 
mainly of gneiss or granite. The sedimentary 
deposits reappear south of the Alps, and in 
the opinion of some high authorities, as, for 
instance, of Bonney and Heim, passed con- 
tinuously over the intervening regions. The 
last great upheaval commenced after the 
Miocene period, and continued through the 
Pliocene. Miocene strata attain in the Righi 
a height of 6000 feet. 
For neither the hills nor the mountains are 
everlasting, or of the same age. 
The Welsh mountains are older than the 
Vosges, the Vosges than the Pyrenees, the Pyr- 
-enees than the Alps, and the Alps than the 
Andes, which indeed are still rising ; so that 
