198 
Mr. Weaver on the 
veins, or alluvial deposits. In each of these divisions, I shall take 
an historical view of the metallic repositories discovered and 
wrought; conceiving records of this nature to be highly useful, 
both to present and future inquirers. 
1. Metalliferous Relations of the Granite and Mica Slate Tracts . 
§ 90. The lead vein at Dalkey, which is situated near the north- 
east extremity of the tract, appears to range in the granite north- 
west and south-east, dipping 70° to the north-east. The outburst 
of the vein is visible near the shore, where it is from four to five 
feet wide, composed principally of disintegrated granite, with quartz, 
in which some little green lead ore is perceptible; but among the 
refuse of the mine we may observe also galena, blende, and heavy- 
spar. The vein does not appear in the hill above ; and hence it 
probably takes a turn more toward the north, following the hollow 
which separates Dalkey Hill from the headland. This mine is at 
present filled up with the sea water. 
§ 91. At Ballycorus (§ 22.) are two veins, the general range of 
which is north-west and south-east, one dipping to the north-east and 
the other to the south-west. At the surface they coincide, but diverge 
as they descend, and also in the line of direction, both to the north- 
west and south-east. In the latter case, the southern vein ranges 
44° east of south from the point of junction, while the northern 
pursues a course 12° south of east. In the fork is granite, but, a 
little beyond it, both veins penetrate and range in mica slate ; yet in 
depth they descend into the granite, which rock alone is traversed 
in their north-western course. 
The workings opened upon these veins extend about 110 
