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Geological Relations of the East of Ireland \ 
and a half to two feet wide, passing through granite and mica slate, 
ranging nearly parallel to the valley, and bearing the same minerals 
as the veins on the north side of the glen. The trials made upon 
this vein were not productive. 
§ 102. A consideration of the tract, over which we have just 
now passed, suggests the reflection, that the powerful agent which 
moulded the glens and vallies, into their present form, appears to 
have operated subsequently to the production not only of the rocks 
themselves, but also of the veins by which they are traversed. 
This seems to be proved by the perfect parallelism, which subsists in 
the direction, and inclination, of the strata on the opposite sides of 
the vallies, and this appearance is uniform throughout the tract 
that we have proposed for consideration; and by the same veins 
pursuing their course without deviation across the vallies, and up 
steep precipices on the opposite sides, as exemplified in particular 
by the great vein at Glendalough, and by the vein in Carrig- 
geenduff. 
2. Metalliferous Relations of the Clay Slate Tract . 
§ 103. The metallic substances found in this tract, are eleven 
in number; namely, gold, silver, copper, iron, lead, zinc, tin, tung- 
sten, manganese, arsenic, and antimony. 
§ 104. In the county of Wicklow, the metalliferous clay slate 
district occupies but a small space, being very narrow in breadth, 
and in length not more than ten miles, extending from Croghan 
Kinshela on the south, through the townlands of Knocknamohil 
