23S R. Chambers, Esq., on Glacial Phenomena 



feet long by fifteen broad, is laid bare by the removal of a 

 coarse brown detritus containing boulders. It presents four 

 bosses, side by side, in the direction of the length, and the 

 whole is beautifully polished, with finely-marked striation 

 across the planes of stratification, being in the direction of 

 N. 46° W.i [Mr Bryce says N. 34° W.,] thus pointing to- 

 wards the eminence forming the west side of the upper and 

 more mountainous portion of the Kent valley. 



A detritus of half-worn blocks mixed up with a brown mass 

 of clay and sand, precisely resembling the moraine matter left 

 at the sides and extremities of existing glaciers, is deposited 

 in various parts of the Lake valleys, in immediate contact 

 with the polished surfaces, and generally in the lee of emi- 

 nences. It is generally where such matter has been excavat- 

 ed for the making and repairing of roads, that we find the 

 best examples of polished surfaces, the detritus having served 

 as a complete protection to the vitreous polish left by the 

 abrading agent. As far as I have observed, the superficial 

 matters do not anywhere, in the central parts of the Lake 

 District, present the peculiar forms of either lateral or termi- 

 nal moraines, except in one instance, in the Thirlmere valley, 

 near its head at Dunmail Raise. There, in the angle be- 

 tween a side valley and the principal one, we find a long 

 ridge of rough detritus with many large blocks, extending 

 down the hill -face. An inexperienced observer would be at 

 a loss to understand the relations in which such an object 

 could stand towards any imaginable glacier hereabouts ; but 

 one who has seen the moraines of the Glacier des Bois and 

 the Glacier d'Argentiere in the Chamouni valley, would 

 quickly perceive that this, in reality, is the right lateral mo- 

 raine of the glacier which issued at this place into the Thirl- 

 mere valley, from one of the high glens which ascend into 

 the mountain chain of Bowfell. Mr Maclaren's moraine in 

 Glen Messan has been surmised as an object of precisely 

 similar history. 



Not far from the moraine just described, on the summit 

 called Dunmail Raise, which is a valley of passage between 

 two ordinary valleys, there is a great mass of detrital matter, 

 through which the infant rills of the district have made deep 



