Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/217

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1868.] KINGSMILL GEOLOGY OF CHINA. 123


Si-kiang, in Kwangtung, the effect of the action of water on the limestone forms the characteristic feature of the landscape; the valley seems originally to have been formed by a wide synclinal curve of the whole series ; except in a few spots, however, the whole of the limestone rocks have been washed away, leaving exposed the grits and slates of the lower beds. The appearance of these detached masses of limestone is described as very fantastic ; of one, Mr. Bickmore writes as follows*: — "About two miles behind the city of Shadking-fu rise the famous marble rocks or 'Seven Stars,' like dark sharp needles out of the low green plain. Mr. Nevin and I measured them with an aneroid barometer, and found them to range from 100 to 150 feet above the plain, though they have been reported as nearly twice that height. The rock is a highly crystalline limestone, of a dark blue colour on the weathered surfaces, and of a rusty iron tinge where large fragments have been detached, the whole traversed in every direction with milk-white veins, and completely fissured by joints and seams." In this province, in many localities, these metamorphosed rocks are quarried, yielding ornamental marbles ; some seem to be so highly altered as to afford a saccharoid marble, approaching in purity the statuary marble of Carrara ; at the " Seven Stars " described above, a coarse marble marked with veins of graphite in zigzag lines is extensively quarried ; it is much used throughout the province for paving, as well as for ornamental screens.

Other similar masses occur along the Si-kiang, near the town of Yueshing in the " Cock's-comb " rock, on the Tung-kiang in the east of the province in the " White -faced " rocks and the " White - horses," and on the Peh-kiang at the " Five Horse-heads," as well as at many unnamed localities. In Kwangsi on the Kwei-kiang or Cassia River, below Kweilin, the provincial capital, Mr. Bickmore thus describes their appearance†: — " On the evening after leaving Pingloh, as we were following the river round a high bluff, we suddenly found ourselves on the edge of a valley ten or twelve miles broad, and extending further than we could see, to the right and left ; in every direction it was perfectly bristling with sharp peaks of limestone. The strata of this limestone were nearly horizontal ; and once the whole valley was filled with this deposit, which in the course of ages has been worn into deep channels that have kept widening, until only sharp peaks are left of what was originally a broad continuous sheet of solid rock. From a single low position on the river bank I counted 192 separate peaks ; the highest was, I judge, 1200 feet over the plain, but even this did not represent the original depth of the formation."

In the central provinces, though by no means so conspicuous, the effects of water on these rocks are still marked ; the strike, as a general rule, approaches closely to an east and west direction, the folds of the strata continuing uninterrupted for many miles. The numbers 1, 3, and 4, containing the harder and more siliceous rocks,

  • Journal of N. C. B. Eoyal Asiatic Society, New Series, vol. iv. p. 2.

† Ib- P. 7.