If m MINERALOGICAL NOTICES 



ward of the mansion-house ; and traced it running 

 in a direction north-east to a short distance from 

 the water's edge. The mica-slate is dark-coloured, 

 very quartzose and small grained ; it includes mag- 

 netic pyrites and small garnets ; and assumes vari- 

 ous aspects in the different strata occurring east- 

 ward, till it passes into the clay-slate of the great 

 quarry, which presents an object of much interest 

 and curiosity to the mineralogist. On the south- 

 west of the granite mass, and along the road from 

 Appin to Balahulish, I observed a similar succes- 

 sion of rocks, including also talc-slate. The gneiss 

 that occurs on either side, is but imperfectly cha- 

 racterised, being very compact, and containing little 

 felspar. A similar remark applies to the mica-slate. 

 But the granite and syenite are extremely beautiful ; 

 and the clay-slate in general, very fine. The sye- 

 nite contains crystals of sphene. Some specimens 

 obtained near the inn, may be compared to the ce- 

 lebrated Egyptian syenite. 



In this formation, there are different beds of 

 limestone, quartz, greenstone, and other usual sub- 

 ordinate rocks. The great vein of greenstone in the 

 slate of the quarry, cannot fail to attract notice. 



Fort-William. — Of the rocks that occur from 

 Balahulish to Fort- William, I have formerly given 

 a general sketch *. I found, then, that the porphyry 

 and clinkstone of Ben-Nevis, are a formation over- 

 laying the mica and clay slate ; the granite appears 



* Wernerian Memoirs, vol. i. p. 319. 



