Ur. Berger on the Isle of Man, 47 



On the slope both of South Bor-roilva and Cronk-ne-lIry-Lhaa, 

 in the southern part of the group of mountains, occur abundant 

 blocks of rather decayed granite, composed of yellowish and white 

 felspar turning to a state of earth, and disseminated plates of white 

 mica. The texture is loosened to such a degree that large frag- 

 ments often yield under the pressure of the hand. 



I traced blocks of the same granite in Glen-Moy, though the 

 bed of the stream is hollowed out in the grey-wacke formation. 



The central stone of a Druidical barrow* in Kirk Ballaugh, is 

 a small grained granite of white felspar, quartz, mica, and a great 

 deal of hornblende. 



ft Mica-Slate, 



A vast number of blocks of mica-slate exist on the slope of 

 Slieau-y-Carnane, another hill in the southern district of the group. 

 The quartz is finely granular, and has a silky lustre, which it pro- 

 bably derives from a superficial covering of talc. The plates of 

 mica are white and sparingly dispersed, sometimes crystallized. 



I met at the village of Craig-neash with a large settled block of 

 mica-slate. The quartz is of a dirty-grey colour. The plates of 

 mica very few and falling into decay. 



fff Porphyry. 



Very numerous blocks of this rock occur on the beach at Aire- 

 point. The basis is compact felspar of a flesh-red colour, turning 



* All the RuJiic or Danish monuments so frequent in the Isle of Man, are (as far as 

 my observation has gone) of grey wacke, without one single exception. The inscriptions 

 they bear are said to be written in the old Norwegian language: they are placed on the 

 edges of the stones, whereas the carvings are on their flat surfaces. The latter appeared 

 to me to bear some resemblance to the form of a snake. 



