Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/146

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136
Mr. William Phillips on the Veins of Cornwall.

mostly north and south, but that he had not known ‘any producing that mineral of more than fourteen fathoms deep.’ The mine called Huel Boys, which formerly produced the triple sulphuret, is now worked for antimony, which occurs in bunches of various dimensions in a vein, the direction of which is nearly north and south, and of about five feet in width. The antimony is accompanied by blende only, and is not now found in a state of crystallization. The country through which the vein runs is schist.

Slide.

Transactions of the Geological Society, 1st series, vol. 2 fig. page 0587 fig. 2.png

Veins, not of a metalliferous kind, but which contain gossan, or flucan, are sometimes found running north and south, with an east or west underlie, generally very quick, one of which will be noticed on a reference to the section of the Manor Old Vein. Veins of this description are also found in the direction of the metalliferous or east and west veins, having an underlie north or south. But whether their direction be east and west, or north and south, and whatever their underlie, they are frequently the cause of much expense and vexation to the miner. When the underlie of this species of vein is in the same direction as that of the metalliferous vein, but quicker, so as to overtake it in depth, the latter is generally divided by the former, and, as it were, removed from its regular course. The load of the metalliferous vein is also sometimes altered in respect to its value, above or below its section, and the space between a and b, Pl. 6. fig. 2. as it regards the load, is as it were lost. This kind of vein, from its direction, has obtained the name of Slide, and the phrase is, ‘the load is cut out by a slide;’ its flucan or gossan, generally traverses that of the north and south, as well as the east and west veins.