176 
SCENERY OF SWITZERLAND. 
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 Kufstein, and 
for some distance along the Enns. Thus, then, five 
great rivers have taken advantage of this main fold, 
each of them eventually breaking through into a 
transverse valley. The origin of the valley is there- 
fore not due to the rivers running through it. Again, 
as a glance at the foregoing map (Fig. 42) shows, 
the great valley of the Aar from the Lake of Neu- 
chatel to Coblenz is continued in the course of the 
Upper Danube. 
The Pusterthal in the Tyrol offers us an interest- 
ing case of what is obviously a single valley, slightly 
raised, however, in the centre, near Toblach, so that 
from this point the water flows in opposite directions 
—the Drau eastward, and the Rienz westward. In 
this case the elevation is single and slight: in the 
main valley of Switzerland there are several water- 
sheds, and they are much loftier, still we may, I 
think, regard that of the Arve (see Fig. 42) from 
Les Houches to the Col de Balme, of the Rhone 
from Martigny to its source, of the Urseren Thai, of 
the Vorder Rhine from its source to Chur, of the Inn 
