Kinahan — On Granite and Metamorphic Hocks. 237 



lings as the granite ; nor are they suited for long bearings, although 

 some appear capable of bearing heavy weights. 



" East-north-east of Crow Hill, near Castlefinn. — Felstone 

 dyke ; speckled greenish-grey ; fine-grained ; nice-looking. 



" Tirinisk, near Castlefinn. — Porphry ; purplish ; spotted with 

 white and dark-green. 



" East-north-east of Crossy Hill. — Felstone ; bright grey ; 

 speckled ; fine-grained. 



" Woodland, near Killygordon. — Euryte ; speckled purplish ; 

 fine-grained." (F. W. Egan.) 



Arran Island, west side. — Porphyry; purplish grey; mottled; 

 speckled with white and black ; compact. 



Bloody Foreland. — Elvan or porphyry ; purplish ; handsome. 



Whinstone. 

 (Donegalyte, diabase, dioryte, doleryte, &c.) 



The majority of the Donegal whinstones are rough and un- 

 gainly, or are rotten, or come out of the quarries in more or less 

 coarse shingle, and are more suitable for road metal than for any 

 other purpose. In places, however, there are really valuable stones, 

 especially in some of the dykes and other intrudes ; but these have 

 been used only in a few places for cut-stone purposes. 



Ballyboe and MiUbrook, a little west of Rathmullen. — Light 

 colour ; green and mottled ; porphyritic to fine-grained ; compact ; 

 durable ; can be raised of long scantling, with considerable transverse 

 dimensions ; capable of long and heavy bearings ; cuts and dresses 

 on any face ; polishes well. 



The local name for the quarry is See-agh, while the stone is very 

 generally called " Ballyboe green granite." About the year 1820 

 the quarries were opened during the building of the forts at Inch 

 and at Rathmullen, while more recently blocks were used in the 

 construction of the Rathmullen Pier ; and for cut stone purposes 

 in pillars for entrance gates, quoins, &c. (J. M'Fadden.) 



It has been quarried in both townlands, and^ hand specimens 

 take a ready and good polish. The porphyritic variety, when 

 polished, is a light-green, with a whitish mottling, and would be 

 effective as columns. Some of the measured blocks were over 15 



