Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/309

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calcareous particles which this does not. It is evidently produced from the disintegration of other rocks, probably those of the chain, and has every appearance of being of very late formation.

$30. On the north-east side of the Worcestershire Beacon, and in the road leading from Great Malvern to St. Ann's Well, I found a rock of a loose coarse-grained texture, with an earthy fracture, composed of mica and hornblende in a state of decomposition, mixed with red felspar. It has a slaty structure, which in some places is more distinct than in others from there being a greater proportion of mica, and its disposition is, within a short space, sometimes vertical, sometimes inclined at a considerable angle, and dipping to different points of the compass; having the appearance of large masses irregularly heaped together. This rock is traversed by a vein of sulphate of barytes about four inches in thickness, and which occasionally includes detached portions of the rock through which it passes. The particular spot where I saw this rock, was where an excavation had been made in the hill round a house newly built, and as the rock was cut down to a considerable depth, a good section of it was exposed to view.

§ 31. The western side of the Worcestershire Beacon is covered with turf, so that whatever rocks occur there, are completely concealed.

§ 32. Between the Worcestershire Beacon and the chasm called the Wych, the rocks, on the eastern side, are similar to those I have already mentioned, except in one instance on the top of the hill, where a rock is found composed of greenish-brown mica, intermixed with hornblende. Although mica is the chief ingredient, this rock has not the slaty structure which most micaceous rocks have, but the laminæ which are pretty large, are irregularly. grouped together, and cross each other in all directions. It is an insulated mass of