of the Vicinity of Dublin, 377 



obtained. The garnet and vesuvlan in these specimens are 

 scarcely to be distinguished from those of Kilranelagh ; and, 

 as at that place, are accompanied by quartz, often of a si- 

 milar greenish colour; with the addition however of blueish 

 grey granular limestone, and of a fibrous substance, not 

 improbably tremolite mixed with carbonate of lime. I 

 have not seen any felspar in the specimens from Done- 

 gal *. 



2. Grenatite — (Staurotide, Haiiy). This mineral was 

 detected bv Mr. Stephens in a micaceous compound of 

 which I found a specimen at the Glenmalur lead mines, in 

 the county of Wicklow : and I have reason to suppose, 

 that it is not very uncommon in the schistose rocks along 

 the south-eastern confines of the granite in that county. 

 The crystals from Glenmalur were small ; but their colour, 

 form, and characteristic crossing, were very distinct, and 

 they were infusible before the blowpipe. 



3. Beryl — (a variety of Emerald, Haiiy). — This was 

 found by Mr. Stephens and myself, imbedded in granite, 

 near Lough Bray, in the county oi Wicklow. (Museum 

 of Dublin College, No. 39.) Mr. Weaver has discovered 

 it in blocks of granite, near Cronebane in the same coun y ; 

 and I have obtained specimens, probably belonging to the 

 same species, in the Dublin mountains, above Dundrum, 



4. ^ndahisite—{Feldspath'apyre,Ha.uy). This mineral 

 has been found by Mr. Stephens and myself, in very distinct 

 specimens, on the north-east side of Doz/ce-mountain, in the 

 county of Wicklow ; apparently imbedded in the mica-slate 

 of which that mountain is composed, and accompanied by 

 quartz, mica, and a remarkable substance hereafter to be 

 mentioned. It differs from the Andaiusiie of Spain and of 

 Scotland, chiefly in possessing an inferior degree of hardness; 

 for although some specimens readily scratch glass, others 

 yield easily to the knife: but the Count de Bournon has 

 observed an equal variation in the hardness of specimens of 

 this substance obtained by himself at Forezf ;-and I have 

 found that of the Scottish stone to vary very considerably. 



This mineral seems to have been first taken notice of, 

 under the name of IVurJlkher- (cubic) Feldspath, by Kar- 

 stent; who took his description from specimens in the 

 Leskean cabinet, now in the possession of the Dublin So- 

 ciety (No. 907-b, &c.) : and by a comparison of these with 



• Tliis compoutid from Donegal has been described by Mr. Sowerby; 

 Briiish Mine.aloj/y, August 18 to, p 133. 



t Jini> mil dr I'imaiiitr, -ixti'iv (1789), p. 453, 



I Bcrgmaniiisclies Journal, vol. ii. (1788), p. 809. 



Vol. 39. No. IC9. Maj/ 1812. • Bb some 



