Page:Transactions of the Geological Society, 1st series, vol. 3.djvu/358

 the Quantock hills. I found there, among the rubbish, specimens of malachite and of brownish-black sulphuret of copper.

I received from Thomas Poole, Esq. of Nether Stowey, a specimen of an exceedingly hard and compact iron ore which had been found in the Quantock hills, but in what place he could not inform me. It is an oxide of an iron-grey colour and semi-metallic lustre, with a sharp splintery fracture, and so hard as to scratch glass easily. Its specific gravity I found to be 5.244, which with its other characters brings it nearer the fer oligiste of Haüy than any other variety of ore. The occurrence of so rich an ore in a large quantity, would be a very valuable discovery.

§ 12. In several parts of this district there are found, as I have already stated, very considerable beds of limestone which are contained in the slate. Their occurrence in detached spots, and their appearance in the quarries where they are most extensively wrought, seem to point out that they are not regular strata conformable with those of the slate above and below them. Flattened spheroidal masses of the same kind of limestone are frequently found, completely enveloped by the slate, and very similar to the balls of clay-iron-stone in slate clay, but thinning away at the edges much more than those do. I conceive that the great masses of limestone occur in the same way: they have an irregular bedded structure, and very often layers of slate, often of considerable thickness, are interposed between the beds; but although the positions of the quarries along the eastern side of the Quantock hills appear in a continuous line on the map, the great variations in the bearing and dip of the strata of those quarries renders it extremely improbable that the limestone of each, although very similar, are parts of regular strata. These beds of limestone appear to be confined to the places where the slaty varieties of grauwacke