GRACE : THE GLACIAL GEOLOGY OF FURNESS. 
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and continuing, more or less clearly, almost to Coniston Old Hall. 
This originated as a strike valley, and owes its canal-like aspect to its 
coincidence with the line of bedding and cleavage of the slates. It is 
not easy to decide how far it had reached northwards before the in- 
terference of glacial conditions. The gap through which Torver Beck 
empties into the lake seems too old to have originated during Glacial 
times, and, if so, indicates that a stream crossing the valley at this 
point was not diverted down the strike valley, and that, therefore, the 
latter had not reached so far. The most probable condition was that, 
from a col near Haverigg Holme, one stream ran south-west towards 
Woodland, and another flowed north-east into Torver Beck, and that 
north-east of the Beck there was no trace of a depression between the 
Fells and the present lake valley. 
The eastern valley, where Coniston Lake now stands, cannot be 
explained so simply. It coincides at the head with a well-marked 
fault, but this disappears about half way down the lake, so that it does 
not account for the valley. Also, the present valley cuts across the 
grain of the rocks, so that it is not structural. It probably originated 
so long ago that the circumstances which began it have disappeared 
and cannot be reconstructed. If our reconstruction of the Torver 
Valley be correct, this eastern valley must have carried the drainage 
from both Yewdale and the Church Beck Valley, and received the Torver 
Beck as a tributary near its present confluence. Its straight course, 
however, suggests that its present form is more due to glacial action 
than to normal erosion. The slopes on its eastern side are lacking in 
any suggestion of spurs, such as might have been expected if it had 
been a normal river valley only slightly modified by glacial action. 
Also the fact that the side valleys which run into it, viz., the Church 
Beck Valley, both the branches of Yewdale and the Torver Beck Valley, 
are all, at some part of their courses, hanging valleys, suggests that the 
Pre-Glacial level of the stream into which they ran was much higher 
than now. 
The profile of the Church Beck has two distinct steps. A smooth 
curve continuing the highest reaches of the stream seems to point to 
the old level of the main valley as being between the 300 and 400 feet 
contours. This estimate is confirmed by the profile of Upper Yewdale, 
which falls from 500 feet co 300 feet in less than a mile, and by the 
Guards Beck, which has a similar profile. If this is anywhere near the 
truth, as the lowest part of Coniston Water is 42 feet below O.D., the 
