NEIGHBOURHOOD OF CORK. 



99 



in detail, separated, however, by another extensive 

 deposition of grey- wacke- slate and subordinate beds 

 of limestone. The character of the rocks are well 

 exhibited in the neighbourhood of Springhill, and 

 on the north side of Bingabella Bay towards the 

 Lee. 



The prevailing colour of the clay-slate is bluish- 

 black, — lustre feebly glistening, — fracture thin 

 straight slaty. This is quarried and dressed as 

 roof-slate. 



About midway between Cork and Springhill, the 

 clay-slate may be observed to include some very 

 thick beds of talc-slate, — of an ochre-yellow colour, 

 — glistening, somewhat pearly lustre, — straight 

 slaty fracture, — greasy feel, — and very soft. When 

 this slate is broken in a slightly oblique direction, 

 the fractured surface appears splintery. In the col- 

 lection of Mr Wright, I observed very perfect, rec- 

 tangular parallelopepidal crystals of iron-pyrites, 

 in a rock of this kind, from Glandore, in the west 

 of the county of Cork. 



In some cases, this rock becomes thick slaty, dull, 

 and the fracture inclining to earthy. Some va- 

 rieties are light in the colour, being bluish-grey, 

 inclining to smoke-grey. Others are darker in the 

 colour, approaching raven-black. These varieties 

 are in general harder than the common clay-slate. 

 Their fracture, lustre, and colour, and appearance 

 when decomposed, reminded me of black chalk. 

 Upon inquiry, I found that black chalk occurred 



