Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/225

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variety, and seemed, making allowance for seven years' exposure, to be of fair quality ; the fracture was bright and clean ; and though the specific gravity was rather low, it was reported to me by the master of one of the Imperial steamers which regularly coaled from these mines during the siege of Nanking, that they had found it of most satisfactory quality. The covering rocks are coarse siliceous sandstones, readily disintegrated and easily removed, from the want of tenacity in the cementing substance. The surface acquires, on exposure, a deep black colour, though the general tint of the beds is a faint yellow. Associated with the coal seemed to be siliceous shales, containing small bullet-shaped nodules of iron pyrites and the remains of a few ill-preserved stems, the character of which was unrecognizable.

With the exception of some Annelid-burrows and tracks in No. 2 and the ill-preserved stems in No. 4, I have procured no fossils to aid in judging of the geological age of these beds ; should they, however, represent those at Hwangshihkang (p. 128) they should apparently be referred to the latter portion of the Carboniferous age. In the north of China a similar series of beds seems to occur (though here I am not speaking from personal experience, nor do my authorities aid me much by their descriptions) ; both anthracite and bituminous coal are found apparently in the same district, the anthracite probably representing the coal-bed in the Tung-ting system, the bituminous the Chung-shan coal. Remains of Cycads have been found in these northern deposits, of the fossils from which Pere David, at Peking, has made a large collection ; and from this the American geologists who examined Mr. Pumpelly's specimens have concluded that the Chinese coal-fields are of Triassic age. Should the fossil mentioned (p. 128) be a Cycad, as seems not unlikely, this would be an instance of that family of plants being found with an undoubtedly primaeval flora — a fact the more interesting as Cycads to the present day flourish in the adjoining country of Japan,

In the province of Chehkiang, in the prefecture of Ningpo, the lower portion of the Tung-ting series is largely developed, quartzites highly metamorphosed and associated with granites and porphyries forming the prevailing rocks ; agates and fluor spar are found in considerable quantities ; while iron, in the shape of magnetic ore of considerable value, is in many places worked to a slight extent, being obtained in the shape of sand from the mountain-torrents. In the Chusan islands, within this prefecture, the coast chain of the northern provinces may be said to end ; and in them, associated with granite, occur portions of these grits, similar in many respects in aspect to the same rocks in Hong Kong. Following the series inland, though the sequence cannot be so readily seen as in the central provinces, we seem to pass over the Tung-ting grits, and in the prefecture of Kinghwa and Hangchow to meet with limestone, which, along the valley of the Tsientang, the principal river of the province, is said to be associated with beds of coal. In the prefecture of Ningpo, near the town of Tszeki, at Ningkong-kiu, in the " Snowy valley," and at many other places there occurs, overlying

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