46 
SCENERY OF swrrzERr.AND. 
near Bern, and turning at a right angle also joins the 
barine. Lastly, the lower part of the valley is oc- 
cupied by the Urtenenbach which joins the Emmen 
and falls into the Aar below Soleure. 
It is clear indeed that there are many dead val- 
eys which have once been occupied by rivers, but 
which are now dry; such as the Klettgau between 
chaffhausen and Basle, which was probably once the 
course of the Rhine, and at another time perhaps of 
Glatthal, between the Upper Lake of Zurich and the 
the Aar; the Rhine at Kaiserstuhl, which was pro- 
bably one of the beds of the Limmat; the valley from 
Oerhkon, by Katzensee to Wettingen, which was also 
once occupied by the Limmat. In some cases the 
rivers have been forced to change their courses by the 
enormous masses of glacial deposits. Thus the Sihl 
was probably cut off from the Lake of Zurich, and 
compelled to adopt its present course parallel to the 
lake, between the Albis range and the great lateral 
Moraine which forms the low ridge of hills along the 
west side of the lake. The Aar again appears to 
have been excluded from its old course down the 
Gauthal by the moraine at Soleure, and driven to 
excavate a new bed in the Mollasse.* 
It IS interesting that these deserted valleys not 
* Du Fasquier, Bcitr. z. Geol. IC d. Schw., L. xxxi. 
