266 Scientific Proceedings, Royal Dublin Society. 



In the National Museum, Leinster House, Dublin, are some 

 fine specimens of Onyx, said to have come from Rathlin Island. 



Armagh. 



The major portion of this area is occupied by Ordovicians in 

 part metamorphosed with which to the S. E. are associated Granyte 

 and allied rocks. These to the N. "W. are succeeded by Carboni- 

 ferous limestone, while the latter, at the N. W. of the county, are 

 overlaid by Triassic sandstone or marl, and to the N. E. by the 

 Tertiary or Cainozoic rocks or the Lough Neagh beds. Some of the 

 rocks near Armagh and to the N. E. at Benburb have been said to 

 be Permian : their position and fossils, however, seem to prove this 

 conjecture to be erroneous. 



The recorded minerals occur nearly solely in the Ordovicians or 

 the associated Granyte and allied rocks. The principal mineral in 

 the lodes was lead, but copper occurred in the veins at Jerret's Pass, 

 near Newry, and Tullydonnell, near Crossmaglen. Griffith records 

 an ancient mine at Ballymore, near Pointzpass, but states its 

 " exact position is not ascertained." 



Lewis reports antimony as having been " found in a few 

 spots." 



Westward of Slieve Gallion in the western slopes of the hill 

 near Larkin's mill, and not far from the edge of the Granyte, 

 either Steatyte or Pyrophyllyte, probably the latter, has been found. 



Carlow. 



The major portion of the area, included within the limits of 

 Carlow, is occupied by Granyte, a part of the Leinster range. To 

 the extreme S. W. of the county is a small tract of Coal Measure a 

 portion of the Kilkenny Coal-field, which lies on the Carboni- 

 ferous limestone of the valley of the Barrow, the latter overlapping 

 the Granyte. These limestones are supposed to lie direct on the 

 Granyte ; but a few small outlyers of Carboniferous Sandstone have 

 been found, which may suggest that elsewhere rocks of this class 

 intervene, but are unknown, being obliterated by the envelope of 

 Drift. 



