in Scotland and Parts of England. 255 



a southerly direction, may easily be interpreted as parts of 

 this grand early system of glaciation, though perhaps par- 

 tially affected by local glaciation at a later period. It has 

 already been stated by Sir Roderick Murchison, that there is 

 no imaginable centre for the issue of glaciers of the ordinary 

 kind down the Gairloch. And the objection is one which 

 apparently cannot be answered. Mr Maclaren has himself ob- 

 served a fact irreconcileable with such a theory in the smooth- 

 ing of the hills of 600 feet high, between Gairloch and Loch 

 Long. I have myself observed, in the adjacent Holy Loch, that 

 the striation, which is there from north to south, indicates an 

 agent which has come slanting over the hill, between that 

 valley and Loch Long, — an eminence of not less height. 



Conformable also are the eastward markings of Strathearn, 

 and the southward markings of Loch Lubnaig. I have lately 

 observed that the valley of Loch Lomond is glacialised south- 

 wardly, the line of its length, roches rnontonnees, with stria- 

 tion, being conspicuous at Bealmaha, Rowandernnan, Luss, 

 and Tarbert. Some islets near Luss are of this character, be- 

 ing precisely like the examples in Ulleswater. Those who are 

 accustomed to affiliate glaciers exclusively to high mountains, 

 would be somewhat surprised to see proofs of such a stream 

 of ice having swept laterally along the base of Ben Lomond. 

 At the same time, I am not sure that the valley of Loch 

 Lomond has not been latterly filled with a local glacier de- 

 scending from some of the elevated basins near its northern 

 extremity, and which, by one of its moraines, may have 

 formed the dam at its foot. A train of granite blocks traced 

 by Mr Hopkins along the side of the loch to a northerly 

 origin is a circumstance pleading strongly for such a theory. 



One example of smoothed and striated rocks at Stronach- 

 lachar, near the head of Loch Katrine, is worthy of parti- 

 cular notice, as utterly destructive of the idea of exclusively 

 local glaciers, and only to be explained by that of an agent 

 wide-spread over the land, plastic, but pressing hard, and not 

 readily yielding to any local obstruction. There is here 

 striation ascending obliquely out of the loch, passing over a 

 high jutting hill promontory, reappearing under compact 

 clay, in low ground, at some distance from the loch, and every - 



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