Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/442

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PROCEEDINGS OF THE GEOLOGICAL SOCIETY.
[June 9,

whatever; but it was found to be quite poor, nearly barren, underneath the granite, though pretty rich above it, and the "horse" dividing the reef gradually widened again in depth, whilst for a good height above, towards the second granite-vein, it had been nearly absent (fig. 6).

The fourth granite vein that traverses the reef is from 5 to 8 inches thick, and dips E. at an angle of about 20° with a slight northerly in-

Fig. 6. — Cross section of the Reef, showing third vein of Granite and "Horse."

Fig. 7. — Cross Section, showing fourth Granite-vein cutting off the Reef (eastern and western veins with "Horse" between) and probable position of lost portion, also granite bottom floor and felspathic vein.

clination. It was struck in the engine-shaft at a depth of 430 feet, where the reef, as a whole, has a width of nearly 50 feet, of which the western vein represents about 20 feet, the "horse" about 25 feet, and the eastern vein 4-5 feet. Beneath the granite all traces of the reef are absent, and only the hard blue metamorphic sandstone of the district occupies the place. The company deepened their shaft through this rock to a depth of 490 feet, when