.METALLIC VEINS.

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of tile vale are but little inclined; the stratain the vale are nearly horizontal, whereverwells or excavations have been made. No dis-turbing force appears to have changed theirposition since their formation. Had a fault ex-isted which rent the island from Nottingham to Macclesfield in Cheshire , it would have leftno dubious marks of its existence in every partof its course*.

Dykes have many characters in commonwith metallic veins, which they resemble intheir position, but not in their contents, Dykesintersect every kind of rock, but metallicveins are principally confined to primary andtransition rocks.

Metallic veins are often separated from the

* Though I differ from Mr. Farey in some of his opinionsrespecting the geology of Derbyshire , I feel great pleasurein bearing my testimony to the general accuracy of his state-ments. His Survey of Derbyshire contains much valuableinformation, and ought to be in the library of every landedproprietor in that part of England. Had the description offacts been kept more distinct from the conjectures, and thelists of mines, &c. been detached from the narrative, itwould have been more generally interesting, and its meritsfetter appreciated.

rocks