Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/169

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159
Mr. William Phillips on the Veins of Cornwall.

from its junction with the east and west vein, and then succeeded 40 fathoms of what the miner terms orey ground.

It seems to be the opinion of a very intelligent and experienced miner, Captain John Davey, who was a captain in Herland mine, and is now the managing captain of Huel Alfred, that the contre of the latter is a continuation of that of Herland.

The east and west, or regular metalliferous vein averages about 21/2 feet in width, and runs 10 degrees south of east and north of west: it underlies 21/2 feet in a fathom towards the north. The ore was about 110 fathoms in length east of its junction with the contre, but the east and west vein is poor every where when in contact with it, except at the only place at which also the contre is rich, viz. at about 117 fathoms from the surface.

West of the contre the east and west vein is lost for nearly 90 fathoms; and when discovered again, it varies from 18 inches to 4 feet in width and its load was found chiefly to consist of flucan with some blende.

The ore of the contre is yellow and occasionally compact, but it is for the most part approaching to black externally; and where richest, is loosely intermingled with small portions of quartz, blende, and iron pyrites, which prevailed very much near the surface.

The ore of the regular vein east of the junction with the contre is also yellow, and for the most part hard; but it is occasionally loose.

The common effect of a cross or north and south vein is that it passes through the cast and west or metalliferous vein, and mostly alters its course, of which numerous instances are shewn on the ground plan of Herland, Drannack and Prince George Mines. A cross vein occurs in Huel Alfred; its effect on the east and west vein is not yet known, but a rare exception to the general rule of north and