Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/123

Rh numerous and well-informed men, who are immediately concerned in mines, to gratify the increasing interest which is felt on geological subjects, by giving to the world occasional details of the many curious facts that almost daily occur in practical mining.

Almost every mine of any considerable depth or extent, is deserving of the notice of the geologist, because each has its peculiarities:—for when two or more mines are on the same vein or veins, there is frequently but little else that is common to each; and even in the same mine, situated beneath a few superficial acres, there is often a strange variety in the dimension, contents, and direction of its veins, and in the country through which these run.

It has already been remarked that the regular or metalliferous veins generally take the direction of about East and West; there are others both in the same and in different directions, most of which are very rarely found to produce any metallic substance; the nature and peculiarities of these will be noticed hereafter. The regular veins are almost uniformly of considerable length; some are known to extend two or three miles, having several mines on their run; and though the idea of their extending the whole length of the county may be judged to be hypothetical, it ought to be noticed that the most experienced miner never satisfactorily witnessed the termination of a vein either on the East or West. Many

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