Mr. Weaver on the Geological Relations of the South of Ireland. 65 



The operations in this mine proved that the 400 tons of lead ore formerly raised, had been 

 derived from a mass of calcareous spar and quartz, firmly adhering to the limestone rock on the 

 northern side, though thinning out in its descent ; while on the southern side a great cavity was 

 found, the general slope of which from east to west, is indicated in the plan and longitudinal sec- 

 tion by the line a .... /S, and its breadth in the transverse section at the respective depths of 

 the 10, 15, and 20 fathom levels, by the transverse lines a . . . h, c . . . . d, e . . . . f. I'his 

 cavity was connected on the east and west with collateral fissures, the greater part of which were 

 filled with loose soil and debris. A bed of calcareous spar, situated on the south, was found to 

 vary from 1 to 3^ feet in thickness, and to be, for the most part, barren, yet contained some 

 disseminated galena. This bed and the corresponding limestone strata dip 33° to the north- 

 westward. 



The whole quantity of ore obtained by these researches, amounted only to 9 tons 2 cwt. 

 2 qrs. of lead ore, and a few tons of blende ; and the works were in consequence discontinued. 

 The lead ore produced 68 per cent, of lead, and the lead yielded 43 ounces 1 1 dwts. and 3 grains 

 of silver per ton. The other metallic substances which incidentally appeared, were pyrites of 

 iron, copper, and arsenic, and iron ochre. The whole may be said to have formed a discontinuous, 

 metalliferous pipe, or erect contemporaneous mass. 



(79.) From the limestone, about half a mile north of Tralee, which is there disposed in hori- 

 zontal strata, seventeen tons of lead ore were extracted in the year 1748, and chiefly, as it woidd 

 appear, from interrupted layers in the rock. 



Lead ore was also found in working a limestone quarry north of Ardfert Abbey in the year 1793, 

 but further research was prevented by the lord of the soil. The part of the heap remaining, con- 

 sists of masses of quartz, containing lumps of galena, calcareous spar, blende, iron ochre, and 

 traces of the blue and green carbonates of copper. 



(80.) A few miles north of Rathkeale, in the tovvnland of Ballintreddedy, has latterly been found 

 in the limestone, a vein, three or four, or perhaps more, feet wide, consisting of calcareous 

 spar, antimonial galena, earthy carbonate of lead and oxide of antimony, grey copper ore, antimo- 

 nial copper ore, blue and green carbonates of copper, and blende. But it has only been touched 

 ujion, the proprietor delaying to make adequate researches. 



(81.) In the townlands of Curraghanadeely and Ballingarane, a few miles also north of Rath- 

 keale, the limestone strata gently undulate from east to west, and adjacent to the line of part- 

 ing between them, the rock is in some places metalliferous, containing an intermixture of galena, 

 blende, iron pyrites, and ochre, a few inches in thickness ; and to these substances is, in some 

 places, superadded calcareous spar, from six to twelve inches thick : but in neither case does 

 the deposit form a distinct bed. Some calamine also incidentally occurs with the other in- 

 gredients. These appearances gave rise to superficial mining operations, which were not at- 

 tended with advantage. 



(82.) To the north of Askeaton, and within a quarter of a mile of the Shannon, in the tovvnland 

 of Ballystein, the limestone contains a bed, dipping 50° to the north, composed of calcareous 

 spar and quartz, bearing lead ore, copper, and iron pyrites, and some blende, and varying from 

 four to sixteen inches in thicT^ness. It was tried upon the range by shallow works eighty fathoms 

 in length, and by two sinkings upon the underlie, of twelve and seventeen fathoms' depth respect- 

 ively, yet apparently without success*. 



* Since the preceding pages were written, some valuable repositories of lead ore have been dis- 

 covered in the carboniferous limestone in the county of Clare, which are deserving of attention ; 



SECOND SERIES. VOL. V. K 



