54 



Sciences. Tome XX., Nos. 12-26 ; and Tome XXI., Nos. 

 1-16. — By the Academy. 

 Proceedings of the Philosophical Society of Glasgow. Nos. 1-1 1 . 

 — By the Society. 



Monday, 15th December 1845. 



Very Rev. Principal LEE, V.P., in the Chair. 



The following Communications were read : — 



1. Notes on the Topogi-aphy and Geology of the CuchuUin 

 Hills in Skye ; and the Traces of Ancient Glaciers which 

 they present— (concluded). By Professor Forbes. 



The first part of this paper refers to the relations of the hyper- 

 sthene rock of the CuchuUin Hills to the adjoining formations. 



The author undertook the observations here d(.4ailed without the 

 shohtest view to publication. He made only brief notes on the spot, 

 collected but few specimens, and drew the first sketch of a map 

 which accompanies the paper, for his own amusement and informa- 

 tion. Finding, however, that the published writings of geologists 

 contained little or no notice of some facts which he had clearly estab- 

 lished, he undertook this paper as a groundwork for future and more 

 systematic researches. 



The details of the geology of the CuchuUins which exist are 

 almost all to be sought for in the Description of the Hebrides by Dr 

 MacCuUoch. The present writer has strong reason for believing 

 that Dr M. acquired his chief information from following the coast 

 in a vessel, and by an excursion to Coruisk, leaving out the more 

 plain and instructive phenomena which the eastern and northern 

 sides of the range pi'esent. Having walked completely round the 

 CuchuUin group, and ascended two of its principal summits, the 

 author thinks that he has established the exact boundary of the 

 hypersthene rock on the eastern and northern sides, stretching from 

 Ben Blaven, which is included within the hypersthene line, by the 

 eastern base of Scuir-na-GiUean, under the noithern slope of Bruch- 

 na-Fray, and so round to Loch Brittle, where it becomes less well de- 

 fined, the hypersthene rock graduating into the common trap of that 

 country. But along the boundary first described the hypersthene 

 may be seen overlying the claystone of the Red Hills, and forming 



