i 7 8 
SCENERY OF SWITZERLAND. 
range. No one who looks at the map can for an 
instant doubt that it is in reality a single valley; but 
it falls into three parts — the eastern portion is oc- 
cupied by a branch of the Dranse running to the 
N. E.; the centre by the Doire running S.W., and 
the west by another branch of the Doire running 
N.E., the two, meeting at the foot of the Glacier de 
la Brenva, fall into a transverse valley and run S.E. 
towards Courmayeur and Aosta. Again the great 
valley which has given rise to the Lakes of Neu- 
chatel and Bienne, and which follows the course of 
the Aar from Soleure to Brugg, reappears in the 
course of the Danube below Donaueschingen. 
In some respects the courses of the rivers indicate 
the original configuration of the surface even better 
than the mountains. 
Many rivers after running for some distance along 
the strike (see p. 66) of the strata, change their 
direction, not turning in a grand curve, but suddenly 
breaking away at right angles, as for instance the 
Rhone at Martigny, the Aar near Brugg, the Rhine 
near Chur, the Inn near Kufstein. 
But why should the rivers, after running for a 
certain distance in the direction of the main axis, so 
often break away into cross valleys? The explana- 
tion usually given is that transverse streams have cut 
