ZtiRICH AND GLARUS. 
173 
Straight for the Lake of Zurich. At Schindellegi it 
is only 3 km. (less than 2 miles) from the lake, and 
no less than 350 metres, or 1150 feet above it. 
Here, however, the moraine opposes a barrier which 
the river has found insuperable, though it only rises 
to about 12 metres above the level of the stream, 
and the consequence was that the Sihl was diverted 
from its natural course. 
The Upper Sihlthal, above Schindellegi, is a 
broad flat valley. The moraine of the Linth glacier, 
however, pushed the Sihl to the west and finally 
excluded it from its own valley. It flowed by Sihl- 
brUck, and Baar, where a broad valley, now dry, 
leads towards the Lake of Zug. This was the 
second course of the Sihl. Its adventures, however, 
were not concluded. During the Third Ice Age the 
glacier of the Reuss occupied the Lake of Zug and 
gradually built up a moraine from Menzingen, east 
of SihlbrUck to Mettmenstetten and on to the north. 
That this moraine belonged to the glacier of the 
Reuss is proved by pebbles of Eurite from the Ma- 
deranerthal, pieces of porphyry from the Windgalle 
and of Gotthard granite.* 
The river thus dammed back, took the only 
Aeppli, Beitr. z. Geol. A" d, Schw.y L. XXXIV. 
