Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/301

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the road which winds round the End-Hill. The rock found in this place is of a dark green colour, of a loose texture, and is composed principally of steatite, with a little felspar and quartz. It is traversed by a slender vein of granite, but as there is a very inconsiderable mass of the rock exposed, I had not an opportunity of tracing the vein but for a very short way.

§ 16. A great part of the End-Hill is composed of granite, particularly on the west side, where it contains veins of quartz in several places. It occurs near the bottom of the hill on the south-east side, and is also found in very large masses on the opposite side of the valley which separates the End-Hill from the North-Hill. In this valley I found a loose black, composed of white felspar, grey quartz, and greenish-black mica, with a little hornblende. In one part of the specimen that I detached from the mass, these materials become more minute, and assume somewhat of a slaty structure. Where this is the case, the mica is more abundant.

§ 17. In the same part of the End-hill, but at a higher elevation than the granite, there is a rock which prevails very much throughout the whole range. It is of a purplish-brown colour, with a fine close grained texture and an uneven fracture. It is composed of hornblende, felspar, and a little quartz; sometimes contains a small quantity of magnetic pyrites, and slender veins of compact epidote; in the fissures of it, crystallized sulphate of barytes and minute rhomboidal crystals of ferriferous carbonate of lime are also occasionally met with: this rock would probably be arranged with the greenstones in the classification of Werner. On the west side of the End-hill, and in some part of the eastern side, a rock is met with, the characters of which correspond very nearly with those of sienite; it is composed of hornblende and felspar, with a few spangles of mica.

§ 18. On the northern side of the End-hill, a rock occurs