to the Mineral Structure of the South of Ireland. 177 



tlerlies and alternates with the undoubted carboniferous lime- 

 stone of the valley of Castle island, is precisely similar to 

 the carboniferous slate which underlies and is interstratified 

 with the lower beds of the carboniferous limestone at Clonea 

 Castle, on the east coast of Waterford, near Dungarvan; 

 it is likewise similar to the rock which alternates with the 

 limestone of Cork harbour, of Killarney, of Kenmare, and of 

 many other localities in the south of Ireland ; consequently, 

 as Mr. Weaver persists in the opinion that the limestone 

 of Cork harbour, of Killarney, of Kenmare, &c, belongs 

 to the transition series, it would be fatal to his argument 

 to class the carboniferous slate of Clonea Castle, or of 

 Currens, with the carboniferous limestone series. But I 

 will observe, that in the localities just mentioned, beds of 

 undoubted carboniferous limestone alternate with slate, pre- 

 cisely similar in fossils, as well as in lithological character, to 

 that of Cork harbour, &c. 



I do not think it necessary to pursue this argument further 

 than to observe, that in endeavouring to form a distinction 

 between the admitted carboniferous limestone of the valley of 

 the river Laune, and that of Killarney, and also between the 

 admitted carboniferous limestone of the valley of the Black- 

 water, below Mallow, and that westward of Clonmeen Castle 

 in the same valley, Mr. Weaver has involved himself in an 

 untenable dilemma. There is no difference in geological 

 position, in mineral character, or in fossils, between the lime- 

 stone of Killarney, and that of the valley of the Laune between 

 Beaufort bridge and Killorglin, which are all contained in 

 the same valley, and all repose on the same base ; and a 

 similar statement may be made in regard to the limestone of 

 the valley of the river Blackwater, above Clonmeen Castle, 

 and that at and below Mallow ; yet Mr. Weaver considers 

 the limestone of Killarney and that above Clonmeen Castle 

 to be transition, and that below Beaufort bridge and Mallow 

 to be carboniferous. 



After what has been said, I hardly think it necessary to 

 reply to the observations contained in the postscript to Mr. 

 Weaver's paper*, in which he endeavours to show that I am 

 incorrect in considering the conglomerate and red sandstone 

 of the Gap of Dunloe, and that to the south of the Lower 

 Lake of Killarney generally, as identical with the red sand- 

 stone, the conglomerate, and red slate of the Cahirconree or 

 Slieve Meesh range. 



* Published in the Philosophical Magazine for June last. [h. and E. 

 Phil. Mag. vol. xvi. p. 471.] 

 Phil. Mag. S. 3. Vol. 17. No. 109. Sept. 1840. N 



