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accumulating a sufficient quantity of evidence of this sort, we 
should be in a position to say whether the ice by which the 
boulders were transported acted as glaciers or as bergs; because, 
so far as the dispersal of boulders is concerned, there is a very 
marked difference in the action of ice under these two conditions. 
This is the sort of evidence that I propose to lay before you 
now, but only so far as the Glacial deposits of West Cumberland 
are concerned, which of course are but a very small part of the 
whole ; but still, I think we may derive from them many valuable 
hints. 
In several parts of the Lake District, occupying very limited 
areas, there are rocks which present such peculiar features, that 
once you become thoroughly acquainted with them, they may be 
recognised anywhere. One of these rocks occurs as a vein on 
the side of Helvellyn and Armboth Fell. It is a quartz-felsite, 
containing beautiful pink crystals of felspar. Boulders of this 
rock occur all the way down St. John’s Vale to Threlkeld, where 
the stream seems to have been split, one part going westward, as 
far as Keswick, the other turning towards Troutbeck. There a 
further division of the boulder stream takes place, and we find 
some of them on the way towards Penrith, whilst others have turned 
round the eastern side of Blencathra, through the valley which 
extends from Troutbeck by Mungrisdale to Caldbeck. Then I 
have found them at Carlisle, Aspatria, Maryport, Flimby, St. Bees, 
and Ravenglass. Nowhere, so far as I know, do they occur at a 
greater altitude than 1200 feet above the sea level. 
Another rock equally distinct in character, and also a quartz- 
felsite, occurs on each side of the northern end of St. John’s Vale. 
Boulders of this rock are found westward down the valley as far as 
Keswick ; and eastward, beyond Troutbeck, on the way to Penrith. 
They also occur in abundance in the Mosedale Valley, on the east 
of Blencathra ; and I have found them at Carlisle, Bullgill, Flimby, 
and St. Bees ; whilst Mr. Goodchild, of the Geological Survey, has 
found them in the Vale of Eden, near Brough. A rounded boulder 
of this rock found in the gravel-pit at Bullgill Station is about two 
feet six inches in diameter. 
