294 Scientific Proceedings, Royal Dublin Society. 



places, however, there appear to be indications of lodes, but the 

 great head of drift, or bog, prevents them from being easily 

 found. 



Sligo. 



The Carboniferous Limestones occupy the principal portion of 

 this area, having on them to the south-east a small but rich tract of 

 Coal Measures, part of the Connaught Coal-field. Crossing the- 

 county obliquely is the Ox Mountain range, the rocks being meta- 

 morphic, flanked in places by Lower Carboniferous Sandstone : these 

 Metamorphic rocks are probably of Cambrian and Ordovician ages,, 

 although, from their lithological characters solely, they are stated 

 by Professor Hull to be Laurentians ; but the penological evidence 

 seems to be conclusive against such an age. At the south margin 

 of the county are small exposures of the Curlew Mountain Silu- 

 rians. 



The coals and clay-iron-stone of the Connaught Coal-field 

 are mentioned in the history of the Co. Cavan. Other iron-ores, 

 however, seem to have been raised, and were smelted at Ballin- 

 togher " and at the base of the Ox Mountains." Lewis also 

 states, when writing in 1837, that " near Screevenamuck are 

 excavations, where the ore was raised as long as timber could be 

 procured for smelting it, the last furnace having been put out 

 in 1768." At Ballynakill, between Ballintogher and Rivers- 

 town, are the ruins of extensive iron works; while limonite 

 appears to have been mined in the adjoining Carboniferous Lime- 

 stone. 



Lead has been worked in the Metamof phic rocks, and silver- 

 lead in the Carboniferous Limestones near Ballysodare; while lead, 

 copper, and barytes have been found and worked in the King's 

 Mountain. The Abbeytown mine, near Ballysodare, has been 

 worked on and off during the last hundred years. In Glen- 

 carberry, King's Mountain, unsuccessful attempts to work pro- 

 fitably the large accumulation of barytes were made between 

 1870 and 1880. 



Well- coloured and well-shaped large amethysts have been 

 procured in the neighbourhood of Ballymote. 



