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Appendix No. 2.
REPORT ON THE GEOLOGY OF THE NEW TERRITORY BY MR. ORMSBY.
The geological formation of this territory is simple, granitic, trappean, and metamorphic rocks largely predominating, the only stratified rocks which are found belonging to the hypozoic period. There are in places evidences of volcanic action, but of a very remote period, while the granitic and trappean rocks are very prominent everywhere. The hills facing Hongkong are chiefly of granite, of which many varieties occur, from a fine close-grained felspathic white rock and a pink coloured granite like that of Aberdeen to a very coarse porphyritic granite. Kao- lin probably exists, but I did not come on any defined beds of it, though told that it was to be found near the west point of Castle Peak Bay. Syenite is common and of very good quality, a dark, highly crystalline variety, in many cases the large distinct crystals of hornblende being well shown.
The bold and rocky east coast shows some very characteristic cliffs of columnar basalt, and blocks of this. an almost black and highly crystalline rock, are largely used for bridging streaus inland.
Further inland other trap rocks appear, while some of the islands in Mirs Bay show very distinctly the terraced and step-like appearance of these formations. The more compact and crystalline varieties seem to predominate, though trap tuffs and claystone porphyries are not absent. Specimens of basalts, greenstones, and felspar porphyries were numerous.
It is extremely difficult in such a country as I have described, where the varieties of trap rocks are so numerous and so mixed up with rocks of the granite system, to say what other rocks may not exist. One thing is certain, there is everywhere an abundance of the best building material, and for road macadamizing nothing could surpass the hard basalts.
In one or two places I came on distinctly stratified rocks, of a hard, crystal- line, close-grained variety, dark grey or bluish grey in colour, which I would call syenitic gneiss.
Pure quartz rock is uncommon, though in places distinct out-crops of quartz- ite were to be seen. I saw no mica schists, and except in the pure granites mica is not to be seen. Talc also is absent, but hornblende appears everywhere, and I should say chlorite schists, hornblende schists and actynolite schists are fairly
common.
I saw no limestone, all lime used in buildings being obtained from the burn- ing of coral or oyster shells.
The lower hills between the mountain ranges are of laterite, rounded or conical in shape, and well covered with vegetation, combining to form the extremely pic- turesque scenery usually associated with such formations. The richly cultivated valleys lying between, formed by the denudation of the surrounding mountains, seemn in most cases to have a few feet of good soil overlying laterite; some exca- vations, as in wells, showed this very distinctly. The laterite is what would be called a coarse cabook in Ceylon, fit for cutting out in blocks for building pur- poses. This is extremely like the disintegrated granite of Hongkong, but contains more silicate of alumina and oxide of iron, the latter showing in large nodules.
Some excellent pottery clay exists on the slopes of Taimò Shán, of which we saw specimens in the village of Un-iu, of a light brown colour and extremely fine texture. Brick clay is found in all the valleys, and is used in the form of large sun-dried bricks in many of the village houses and walls.
Possibly beds of primary limestone will be found, but the lime obtained by the burning of coral or shells is as a rule better for building purposes, so the absence of rock limestone, if such turns out to be the case, does not matter. A lead mine was worked for some years on the side of Taimò Shán, but the working discon - tinued for some reason about 6 years ago. Galena was also found near Kowloon, and on the north side of Lantao, and elsewhere. These workings should be ex- amined by a mining expert, and the richness of the ore ascertained. The natives also speak of alluvial tin being found. Silver and lead were worked on the south of the island of Lantao within recent years, but without success financially, possibly due rather to Chinese official interference and bad management than to the absence of a paying richness in the ore. Expensive buildings were erected on the sea-shore, and machinery said to have cost 100,000 dollars imported and erected. Even
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