116 GEOLOGY OF ARRAN. 



ought to be evidences of it on the shore, where all the strata 

 are well exposed. Certainly none of the limestone beds of 

 Maoldon are seen upon the shore. We cannot agree with 

 the view stated by Murchison and Sedgewick, that there is 

 a series of advances of granite from the central ridge. From 

 the north side of Glen Sannox to the mill-dam, the line of 

 junction of the granite and slate is extremely uniform, un- 

 broken by spurs advancing from the granite nucleus. We 

 believe that when the paper on Arran by these distinguished 

 geologists was written, and even six years later, when Mr. 

 Ramsay wrote, the fact was not properly recognized, that in 

 the Scottish carboniferous system bands of limestone may 

 occur anywhere from top to bottom of the series. 



There is little else worthy of notice here; it is a wild 

 bosky place, encumbered with huge fallen masses of sand- 

 stone, and with granite blocks, among which many pretty 

 ferns and flowering plants find suitable habitats. But there 

 ai-e adders also about, and it is well to be watchful. The 

 north and north-east fronts of Maoldon are very precipitous ; 

 the western part of the precipice is intersected by a green- 

 stone dike about fifteen feet broad, ranging north 25 west 

 and inclined towards the east at an angle of about 15. It 

 forms a deep chasm in the cliff, over which the sandstone 

 rises in a lofty wall. The amount of wearing here is pro- 

 digious ; and we cannot conceive how it can have been 

 effected without the action of the sea. Yet the place is 

 many hundred feet higher than the ancient level, indicated 

 by the raised beach so often mentioned already. We must 

 therefore call in the agency of the sea during the elevation 

 of the land at an earlier period. Through a narrow passage 

 between the dike and the sandstone wall, we can ascend to 

 the top of the cliffs. A remarkable alteration is produced 

 in the sandstone by this great dike. The top of Maoldon, 

 about 1206 feet high, is composed of soft red sandstone, 

 dipping S. 25 E. at angles of 15 to 20; and thus the 

 strata are "end on" to the granite. Impressions of plants 



