226 
SCENERY OF SWITZERLAND. 
Yet though the Val Leventina corresponds in so 
many respects to the Reussthal, in others they pre- 
sent great contrasts, and as we cross the pass the 
sceneiy changes like magic. The two valleys are, in 
the words of Rutiraeyer, twin brothers indeed, but 
brought up in a different climate, and clothed in a 
different dress. 
The valley of the Ticino, in the boldness of its 
features, the grandeur of its dimensions, and the 
beauty of its colouring, has certainly no superior in 
the whole Alps. 
From the quantity of snow which falls in the 
upper valley, the frequency of avalanches, and the 
character of the rock, we see here the effects of de- 
nudation on a scale which cannot be exceeded, and 
is hardly equalled, elsewhere. 
Below Airolo the valley is divided into succes- 
sive stages separated from one another by narrow 
gorges, corresponding to the sections already de- 
scribed in the northern valley: (i) The short piece 
between Airolo and Stalvedro, which really forms 
part of the Bedrettothal, corresponds to the Urseren- 
thal on the north side of the mountains: the gorge 
at Stalvedro is due to a ridge of Gneiss; {2) the 
section from Stalvedro to Dazio Grande; (3) from 
Monte Piottino to Calonico; and (4) the broad river 
