Dr. Berger’s Account of the Isle of Man . 487 
of quartz veins traversing several contiguous blocks, may be known 
to be still in situ . It will readily be conceived that the granite 
found in working the Foxdale mines, mentioned by Dr. Berger, 
page 36, was a continuation of that forming Slieu-ny-Clough, since 
the southernmost shaft is within gun-shot of the spot where we 
first meet with it denuded on ascending the course of the river, 
QUARTZOSE DISTRICT. 
By this title I wish to designate three localities, throughout 
which the prevailing ingredient of the rocks is quartz, and as 
I know not under what head to class them, I prefer giving a 
description of their appearance to hazarding a conjecture. No good 
section is afforded which might enable us to compare their connexion 
with the other formations, some quarries however occur at intervals 
which give us an opportunity of examining their structure, which 
in several places consists of quartz only, very crystalline and finely 
granular, and would deserve the name of quartz rock, were it not 
associated with other varieties. The first district to be mentioned 
lies between the Dun granite and Slieu-Roy, on which latter 
mountain many large blocks are scattered, which lie bleached 
on the surface, and at a distance present the appearance so 
commonly exhibited in granite regions. A section on the west of 
the mountain shews this rock intimately associated with the clay- 
slate in broad contorted beds, the composition here consisting of 
the same ingredients as granite in a very comminuted state ; but 
the general character of the scattered blocks is that of a genuine 
quartz rock. 
To the south-east of South Barrule and Cronk-ny-irrea Lhaa, 
the quartz is blended with mica and specks of clay-slate, sometimes 
with the latter only, presenting an intermediate passage between 
Vol. V, 3 Q 
