Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/157

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147
Mr. William Phillips on the Veins of Cornwall.

The general direction of the metalliferous veins is a little from the north of the east to the south of the west, and of the north and south veins or Cross Courses, a little from the west of the north to the east of the south.

Herland and Drannack and Prince George mines, and that called Huel Alfred, a description of some peculiarities in which is annexed, claim peculiar attention, as well on account of their being in immediate contact with each other, as because their situation in a schistose country, seems almost the only circumstance decidedly common to both. In almost every thing that respects their veins, it would perhaps be difficult to point out two mines more completely at variance, except that in each there occurs one of that denomination which is termed a contre.

Most of the east and west or metalliferous veins of Herland and Drannack mines varied from 2 to 6 inches in width, and whenever found to exceed the latter size, it proved an indication that they were about to diminish, and in the language of the miner, to pass away in the run of some fathoms in mere strings—a circumstance of extremely rare occurrence in the veins of Cornwall: they were consequently abandoned, because they no longer paid the expense of pursuing them east or west. It may well be supposed that considering the narrowness of these veins they were extremely rich; in fact they were so rich that it was frequently the practice of the miner, after taking away one side of the vein, to spread canvas to receive the load. That vein called the Manor Old Load exceeded the rest in width, being in the largest parts from one foot to one foot and a half in width, and the ore was occasionally found in floors of two or three feet wide, a circumstance more common in tin loads than in those of copper.

The direction of the contre is somewhat to the north of the west

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