HOURS AMONG ROCKS AND CLOUDS. 367 



action of water upon the loosened soil. Hence it is toilsome work to cross this 

 turbary from one eminence to another, and amidst rain and mist confusing and 

 confounding. No lady tourist should suffer herself to be tempted to an eminence 

 where the roughest gales are eternally battling with each other, for assistance is 

 scarcely available in some places, and I was witness, on my last ascent, to the 

 unpleasant incident of a lady being violently hurled to the earth by the fierce 

 wind, in spite of every effort, while her veil and bonnet sailed, beyond the ken 

 of vision, over the precipice. Blood profusely flowed from her head, meeting the 

 sharp rocks in her descent, and though little beyond fright eventually ensued, 

 such disasters to females are not very pleasant. 



The great mass of Plinlimmon consists of primary Slate, which has, however, 

 been subjected to an unpleasing process by the vicinity of Trappoid rocks, and 

 their injection into its strata from beneath. Hence, though the masses in situ 

 are mostly concealed by turf and Sphagni, the inequalities of the surface, and 

 the Quartzose fragments scattered around, give abundant evidence of the process 

 that has taken place in the magnificent crucible of Nature. Schistose piles occur 

 in various places on the ridge, vertically elevated and serrated sharp as a needle, 

 whilst at intervals, amidst the elevated plain and turbary, broad masses of 

 Quartz appear like heaps of snow starting from the Moss. The elevated points 

 around the turbary are mostly Trappean Quartz, the loosely-crystallized pre- 

 dominating ; and close to the highest point I found a beautiful slab of Siliceous 

 crystals on Greenstone. The whole mountain, therefore, must be considered as 

 modified by igneous agency, although the mosses and bogs that conceal its 

 rocks derogate from that magnificent regal aspect which most hills of eruptive 

 character assume. The sides and buttresses of the mountain betray the 

 same origin as the summit, for I noticed, close to Blaen Hafren, huge masses 

 of indurated rock in the infant Severn, penetrated with Quartzose veins, and 

 a rock of similar appearance presented itself higher up the stream. By the 

 side of the Rhydol Pool I also observed a mass of Breccia, the pebbles composing 

 which were very smooth, as if subjected to the attrition of water ; but the con- 

 nection of this mass with the Schistose strata Was not apparent. A dome of 

 Whinstone of enormous size is mentioned, by the anonymous writer in the 

 Cambrian I have before referred to, as occurring in the ascent of the hill from 

 Machynnleth, but this did not come under my notice. The dependent buttresses 

 of the mountain towards Pont Herwid on the Aberystwith-road abound with 

 Lead-ore, interjected probably into the rock when in a fluid state by the igneous 

 action from below ; and so great is the quantity this vicinity has yielded, that it 

 bears the appellation of the Welch Potosi. 



Every elevated point on Plinlimmon is crowned with cairns, which are con- 

 tinually increased by the hands of idle shepherds, so that some of them form 



3c2 



