Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/158

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Mr. William Phillips on the Veins of Cornwall.

and south of the east: it produced a considerable quantity of copper ore, and varied from one to three feet in width. Near the surface great quantities of blende and iron pyrites were found in it. Wherever it intersected the east and west veins, their contents formed together one load at the junction for about eight fathoms in length and three or four in width. That part of the contre west of the cross vein called the Privateer Flucan was heaved by it northwards two or three fathoms, and the substances of both were mingled together. By Harvie's cross course it was heaved eight fathoms, and the substance of the cross course between the divided parts of the contre was found to be nearly twice its usual size, and consisted not of quartz only but of quartz mingled with iron pyrites, blende and copper ore, so that both the cross course and the contre in part lost their peculiar characters. The contre continued both N.W. and S.E. beyond its working, but was poor.

The substances of the numerous north and south veins or cross courses of these mines were quartz or flucan, or both. By the ground plan some variations will be observed in their directions, as being more or less to the west of north and south of east: it will also be seen that, their general effect is to alter the course of the veins they traverse, by heaving, in the phrase of the miner, the western parts of them higher north, but with some exception, for the reverse was the fact in respect to those parts of the Manor Old Load and Middle Mine Load traversed by Chambers's Flucan and the Great Cross Course.

The discovery of silver in one of the north and south veins of these mines has already been made known by the publication of Mr. Hitchins's paper on that subject in the Philosophical Transactions. It may however not be amiss to take some notice of that peculiar circumstance. It was found in that part of Convocation