Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/373

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rocks occur, and at their greatest elevation as at Smokeham, Crowcombe and Bagborough, but it appears to lie always above them. I did not find it in any one instance covered by the conglomerates or their accompanying sandstones.

§ 31. In the eastern part of the district near the banks of the Parret below Bridgwater there is a nearly insulated hill called Cannington Park, totally different in structure from any other part of the country described in this paper. On the north side it rises directly from the marsh land, with a gradual slope, to the height of 232 feet above the plain: on the south side it is not altogether cut off from the lateral branches of the Quantock hills. It is composed of a highly crystalline limestone, of a pearl grey colour, having a very close grain, and when struck, giving a ringing sound like that of glass. I examined it with very great care, in order to discover whether it contained any organic remains, and particularly at the decomposed surfaces, and in those places where the stone was bruised by the blow of the hammer, which generally detects any madrepores that exist in a limestone, but I could not find the slightest trace; and some of the quarries who had worked there for several years, told me that they had never found any thing of the kind. It contains here and there contemporaneous veins of a very pure white and opake calcareous spar, and the strata are traversed by large veins of calcareous spar. In the latter veins the spar is distinctly crystallized, and in layers parallel to the sides of the vein, a circumstance which points out a marked difference between them and the veins of contemporaneous formation. On the north side of the hill there is a vein of red sulphate of barytes, about three feet thick in the widest part. This substance is not contiguous to the limestone, but is accompanied on each side by a reddish brown ochreous earth. Nor does the vein itself appear to intersect the