DIRECTIONS OF RIVERS. 
215 
Indeed, the general slope being from the ridge 
of the Alps towards the north, most of the large 
affluents of rivers running in longitudinal valleys 
fall in on the south, as, for instance, those of the 
Ist;re from Albertville to Grenoble, of the Rhone 
from its source to Martigny, of the Vorder Rhine 
from its source to Chur, of the Inn from Landeck 
to Kufstein, of the Enns from its source to near 
Admont, of the Danube from its source to Vienna, 
and, as just mentioned, of the valley from Yverdun 
to Waldshut. Hence also, whenever the Swiss rivers 
running east and w'est break into a transverse valley, 
as the larger ones all do, and some more than once, 
they invariably, whether originally running east or 
west, turn towards the north. 
But why has the plain of Switzerland this slope? 
Why is it lowest along the wall of the Jura? As 
has been already pointed out, this part of Switzer- 
land was formerly a sea, which was gradually filled by 
river deposits'. It is indeed a great “cone” due to 
many rivers which flowed down from the rising Alps. 
This being so, the general slope is naturally up to, 
and the lowest part is that farthest away from, the 
mountains. 
In considering the courses of rivers it must be 
remembered that the strata situated below by no 
