342 
Mr. We a v e r on tJje 
more on the east and Newport on the west, is a red coarse conglo- 
merate, very similar to the rock of Lyons and Dunabate. The best 
millstones are sold here for ten guineas the pair. In this part, 
the sandstone rests unconformably on clay slate, and toward Silver- 
mines the latter rock may occasionally be found supporting the 
former in isolated portions. In the eastern quarter of this chain, 
the sandstone occurs both of a coarse and fine grain. 
§. 140. This clay slate nucleus has yielded lead, silver, and 
copper. To the south of Kilboy, the seat of Lord Dunally, 
and of the village of Silvermines, extensive superficial works 
were carried on during part of the last century, between the 
townland of Knockenroe on the east and Gurteenadya on the 
west. They were resumed in Gurteenadya in 1801, but in 1807, 
when I visited them, the operations were not attended with 
success. The field of enterprize was of a peculiar character. Let 
us figure to ourselves an open space, formed in the line of the 
apposition of the limestone upon the clay slate, and probably pro- 
duced by the subsidence and parting of the former from the latter 
rock on the declivity. This space is several fathoms wide at the 
surface, but it contracts in descending, and finally closes at the 
depth of about twenty-five fathoms. It was filled with clay, 
sandy clay, sand, decomposed slate, and scattered blocks of lime- 
stone, lydian stone, and sandstone ; the whole mass being more or 
less cemented or penetrated by metallic depositions, consisting of 
iron ochre in various stages of induration, iron pyrites, white lead 
ore, galena, malachite, copper pyrites, and blende, with calcareous 
spar and heavy spar. In this softness , (as it is locally termed by 
the miner,) the old adventurers conducted their operations, and 
obtained, it is said, considerable quantities of lead rich in silver i 
acicularly crystallized white lead ore having been particularly 
abundant. 
