36 Mr. Weaver on the Geological Relations of the South of Ireland. 



but which on the sides decline toward the limestone plain, under angles varying successively in 

 different quarters from 60° to 40°, 30°, 20°, and even as low as 15° and 10°. The superposition 

 of the limestone to the sandstone may be traced in some places, as at the western ends of the 

 ranges of Kilmeady and Knockaderry ; and near the points of contact the limestone is sandy. 



Looking to the composition and structure of Knockfeernagli, it may be 

 presumed^ that all the three ranges derive their forms from subjacent ridges of 

 greywacke and slate, the sandstone conforming to their surface. In the pro- 

 truding knoll of Knockfeernagh, the greywacke and slate range to the east 

 and west, dipping 85° to the north ; but in the defile below, which traverses 

 the range from north to south, on the east of the knoll, there exposing those 

 rocks, they dip 80° to 85° to the south ; the opposite dips doubtless arising from 

 a flexure of the strata in their descent. They are here surmounted by beds 

 of sandstone and red slate-clay in nearly horizontal position. The projecting 

 knoll above is surrounded by the sandstone on every side, and the greywacke 

 and slate which compose it may be described as follows. 



A base of clay- slate more or less incorporated with mica, or chlorite, or quartz, and enveloping 

 rounded or angular fragments of hornstone, quartz, and slate; usually containing also, scattered 

 through the mass, scales of silvery mica, particles of vitreous quartz, and more rarely fragments of 

 felspar. Calcareous spar, more or less disseminated, is also not an uncommon ingredient. When 

 in a state of disintegration, the exhibition of yellow and brown oxides of iron becomes very abundant. 

 The same rocks, in the defile below, partake more of the character of a compact clay-slate or nova- 

 culite, enveloping some of the other ingredients mentioned. These include a bed of stratified quartz 

 rock, about ten fathoms thick, consisting almost wholly of simple granular quartz- rock, closely 

 consolidated, and exhibiting a small splintery fracture. 



(49.) I have already remarked (§. 10. and §. 13.) that in the western quar- 

 ter of our field, the old red sandstone of Slieve Meesh overlies the transition 

 rocks of Cahirconree in their range to the eastward ; and that they reappear 

 more east from beneath the old red sandstone, forming a low ridge of grey- 

 wacke, which crosses the river Maine near its head : partly separating the 

 vale of the latter from that of Castle Island, and supporting there, on each 

 side, the carboniferous limestone. 



The old red sandstone of Slieve Meesh may be best studied from the north- 

 ern side, where it is penetrated by deep sinuous glens and ravines. The 

 southern side of the range being little interrupted, does not present the same 

 facilities for observation. Between three and four miles to the south-west of 

 Tralee is the mouth of Curahene glen. At two and four miles east of this, 

 respectively, are the two mouths of Blennerhasset's glen, the more distant 

 being adjacent to the old road leading from Tralee across Slieve Meesh to 

 Castlemaine. Two miles still further east, are ravines adjoining the old road 



