272 Scientific Proceedings, Royal Dublin Society. 



south of the county and the Co. Limerick. These furnaces and 

 mills were at work until the woods were exhausted ; the last fire put 

 out (Woodford), about the year 1750, belonged to the Burkes of 

 Marble Hill. 1 



In the Ordovician rocks in different places are found, besides 

 the iron ore (limonite), small veins and indications of lead, sulphur- 

 ore, copper, anthracite, plumbago, &c. ; but up to the present 

 time none of them have been worked very successfully. 



Cork. 



The rocks of the premier county of Ireland are both interesting 

 and peculiar. North of the valley from Dingle Bay, Co. Kerry, 

 to Dungarvan, Co. Waterford, there is one type of Carboni- 

 ferous rocks, while south of that line there is another. In the 

 north-west part of the county, in the Ballyhoura and Galtee 

 Mountains, there is Carboniferous Sandstone, within the latter a small 

 exposure of Ordovicians. Over the sandstone lies the Carboniferous 

 Limestone, and on the latter Coal Measure, a part of the West 

 Munster Coal-field. 



But south of Dingle Bay and Dungarvan Valley the rocks 

 have lithological characters, more or less peculiarly their own, 

 which have lead to various classifications and nomenclature. The 

 petrology, or the geological relative positions, of the different groups 

 have been very successfully worked out by Griffith and Jukes ; but 

 to suit the present ideas their names require revision, or rather modi- 

 fication. In this area there is very little limestone, it only being 

 found to the eastward, while elsewhere it is replaced by shales, 

 slates, and grits {Carboniferous Slate) ; these towards the west are 

 of considerable thickness, being much thicker than the Carboniferous 



1 In the Geology of Ireland (1878), chap, xxi., p. 352, and in other writings on the 

 subject, I have suggested as probable that the last furnaces in which wood charcoal 

 was used for smelting iron were those of Woodford in Gal way and Port Eoyal in Mayo. 

 Since then I find that the Port Eoyal works appear to have heen in existence subse- 

 quent to those of Woodford ; while in Leitrim and Sligo there were fires alight in 

 1765 and 1768, or nearly twenty years later than at Woodford. The fires at Shillalagh, 

 Co. Wicklow, were put out a few years before Chamney's death, which took place 

 in 1761. The Port Royal works seem, however, to have been more recent than those 

 of Sligo and Leitrim, as, about the year 1860, the old mill was partly in existence, the 

 forge anvil being still in situ, — (See Mayo, p. 290.) 



