Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/222

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In the same series in the Suichang district, and, indeed, all along the south bank of the Yangtse where this rock is exposed, a deposit of coal occurs. It seems to be a semianthracite mixed with a considerable amount of argillaceous impurities ; the structure is somewhat lenticular, readily breaking into conchoidal lumps with smooth bright surfaces. In no locality have I found more than a single seam averaging some 3 feet in thickness. Though of inferior quality, from its frequent outcrops (owing to the convolutions of the strata) it has been worked to some extent by the Chinese— these mines, however, being generally little more than surface workings, a shaft some 3 feet high and perhaps 2-1/2 feet wide being driven into the hillside at an angle of about 45° with the horizon till the coal is struck. No system of drainage is attempted, the holes being generally situated at a sufficient elevation to admit of a natural exit for the water. The seams being for the most part vertical or highly inclined, no galleries are driven, the coal being only removed from the immediate neighbourhood of the shaft, up which it is carried by naked boys in wicker sleighs.

For most purposes this coal is unsuitable ; a similar kind brought down from Hunan, however, is burnt to a considerable extent by the steamers trading between Hankow and Shanghai ; it throws out a considerable heat, but, from the amount of extraneous matter contained in it, is apt to run to slag and choke the furnaces. The seams seldom crop out at any considerable altitude, so as to allow of free drainage if worked deeply, while the quality and thickness of the seam is not sufficient to render heavy machinery profitable. As the coal occurs in immediate proximity to iron, it may possibly be found useful for smelting at some future period. I have found only one fossil in connexion with this bed in anything like a good state of preservation — the leaves are set alternately, and have a well- marked midrib with parallel striae, which seem likewise to be continued in the stems. There is, however, a possibility of this plant belonging to the same bed as those before noticed (p. 121), the exposure of the rocks not being sufficiently continuous.

Taking the whole Tungting system there is a striking resemblance between it and the Devonian and Subcarboniferous rocks of the south of Ireland — the same succession of grits and shales at the bottom, and a similar development of limestone above ; while the type of the few fossils found seems likewise to approach that of the Lower Carboniferous rocks of Europe.

With No. 8, described in the Table as the Upper Limestone, the system, so far as my knowledge extends, ceases ; I have in no locality been able to trace the ascending sequence. On the Yangtse, however, immediately to the west of the Suichang district described above, a series of coarse sandstones and quartzose grits interspersed with brownish shales succeeds, though apparently not conformably. Near the village of Hwangshihkang, situated on the river some seventy miles below Hankow, these rocks are largely developed ; the prevailing dip is E. or W., or nearly at right angles with the older rocks, which are found in bold hills overhanging the river a few miles lower