S. Hyde — Deep-mining in the South-ivest of Ireland. 251 



these axes ; the lodes, on the contrary, following the strike of the 

 beds, though varying much in underlay or hade. 



The productive mineral ground of this part of Ireland appears to 

 be chiefly confined to a zone in the upper part of the Old Eed Sand- 

 stone or base of the Yellow or Upper Old Ked. Gray and green 

 argillaceous and arenaceous slates, with pale green, coarse-grained 

 saccharoid sandstones, constitute the chief lithological features of the 

 cupriferous series. Six or eight such zones are exposed through the 

 agency of the anticlinals and synclinals above-mentioned, caused by 

 subsequent denudation, which has removed much of the superincum- 

 bent Upper Old Eed. They are, however, only portions of the same 

 beds or zone thus exposed along given north-east and south-west lines. 



The general bearing of the lodes therefore in the south of Ireland 

 is according to the strike of the strata containing them, though they 

 do not always follow the dip of the beds, as believed by some : every 

 angle of inclination being observed through an extensive series of 

 lodes; for example, the seven lodes of Ballycummisk at Eossbrin 

 Harbour underlay all south at steep angles, the Ladies' vein at the 

 210 fathom level being 85° or 1 in 12 ; Pope's old lode the same, 

 from the surface to the 198 fathom level. 



We cannot attempt to compare the veins of this region in the 

 order of dates, or according to their antiquity and different directions; 

 sufficient is not known of them or their history, and the elvans which 

 traverse and alter them are not sufficiently understood. It is to be 

 hoped, however, as the science and practice of miaing advances in 

 Ireland, that these important questions will receive attention and 

 solution. 



I can scarcely enter into any particulars relative to the now 

 well-known Ballycummisk mine, which is in all its features a 

 type and evidence of what can be, and it is hoped will be done, 

 for deep-mining in the south-west of Ireland. It is also be- 

 lieved that the Bearhaven and Ballycummisk deep workings will 

 be the means of elucidating much of the physical structure of this 

 area, and aid us in arriving at some general and definite rule or law 

 as to the true mode of occurrence and in-filling of the lodes in the 

 south-west of Ireland, and their relation to those of Cornwall ; for up 

 to the present date but little reliable data seem to have been arrived 

 at, that may lead those interested in the mineral wealth of the country 

 to draw any definite conclusions from practical results. 



Deep-mining has therefore been partly condemned, chiefly perhaps 

 from the peculiar nature and character of the geological formation or 

 structure of Kerry and the south-west of the County Cork districts, 

 and the abnormal conditions under which certain copper ores appear 

 to exist in the "gangue" or matrix which contains them ; and much has 

 been written relative to this area, and notably in the "Memoirs of the 

 Geological Survey," in explanation to certain sheets descriptive . of 

 the Physical Structure and Geology of the south of Ireland,^ and in 

 which the views of the several authors are given, as well as clearly 



1 Nos. 200, 203-5, 199, 1861. 



