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valleys of the island, Sannox, Kosa, lorsa, and Eis-na-Vearraid, 

 radiate in all directions, their extremities opening on the seaward 

 belt of low land. If glaciers ever existed in Arran, under the 

 subarctic climate to which Scotland was once subjected, these 

 central heights must have been the seat of the snow-fields which 

 fed them, and the radiating valleys the channels down which 

 the viscous mass of glacier ice must have pushed forward to 

 debouch upon the low ground, and melt under a higher temperature. 

 On the sides, then, and towards the openings of these valleys, we 

 should expect the effects of glacial action to be most distinctly truce- 

 able in the striation and polishing of the subjacent rocks and trans- 

 ported masses, and in the formation of lateral and terminal moraines. 

 Many broad surfaces of the natural rock are exposed both on the 

 sides and in the bottoms of these valleys, favourably placed for 

 receiving such impressions under the grinding action of a descending 

 mass ; yet have we failed in detecting more than a few cases of 

 striation and polishing, or of that "moutonne" character of sur- 

 face, which is referable to the action of moving ice. A granite 

 surface is, however, very unfavourable for the preservation of 

 such markings, especially the Arran granite, which is generally 

 of such structure as to be subject to rapid disintegration. The 

 slate is better fitted to retain impressions of this kind, its tough- 

 ness and fine-grained structure rendering it less liable to decom- 

 position; but it is seldom exposed in favourable situations, and is 

 rarely found striated. Granite bosses in the glens, and on many of 

 the lower ridges, have that peculiar rounded character, due to the 

 action of ice, to which the term "roches moutonnees" has been 

 applied ; but perhaps none of the cases can be decidedly referred 

 to glacial action, on account of the peculiar spherical structure so 

 often assumed here by granite on the large scale. On the slate 

 ridges, however, beyond the granite border, some well marked cases 

 do occur, as on the plateau to the south-west of Goatfell. We have 

 already in previous articles called the attention of the student to 

 many undoubted instances exhibiting these appearances much better 

 than anything in Arran. 



But though these more direct evidences are so rarely met with 

 here, there are others scarcely less satisfactory, and of more frequent 

 occurrence. These are the terraces and mounds of transported mate- 

 rials on the sides and at the openings of the glens, and the dispersed 

 blocks in every part of the island. 



The terraces and mounds consist of earth and rounded masses of 

 rock, irregularly mixed without reference to weight, and in such 



