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CHINA. I. Geography and Statistics. Physical Geography.—Important additions to our knowledge of the physical geography of China were made within the period 1875-1900. Chief among these is the work of Baron F. von Richthofen, published at Berlin in 1882, including his geological maps of the northerly part of the empire. The hitherto unknown tracks of western and south-western China have attracted numerous travellers, and the trade routes and markets of Szechuen and Yunnan have been explored and described by officers of the British consular service. And within the last year or two of the 19th century private enterprise undertook a survey of the whole route from the Burma frontier to the Yangtse at Chungking, with a view to the construction of a through line of railway. Several eminent French explorers have traversed the same region with the like object of finding a feasible route from Tongking into Szechuen. For details reference should be made to the works cited at the close of this article, but the following general remarks on the country as a whole are submitted. The ancient stratified rocks of China form beds of stupendous thickness. Of these the most widely diffused is a characteristic limestone to which von Richthofen gives the name “ Sinian,” its prevalence being so universal that it deserves to take its name from the whole country. In the provinces bordering on the lower Yangtse this limestone belt occupies the centre of a group of formations,— the lower being quartzose sandstone and argillite schists, and the upper again argillaceous sandstone often locally altered into quartzite. In Szechuen the limestone attains a thickness of upwards of 11,000 feet in some parts. Extending, as the formations do, over nearly the whole of China, they vary indefinitely in their relations to one another, but the whole points to a long period of quiescence when the central and northern parts of China were submerged under deep water. The period corresponds to the Silurian and Devonian epochs in the geology of Europe. Outflows of granitic rock and other violent disturbances brought the period of quiescence to a close. Over the limestone formations there is next found a series of Carboniferous strata almost equally widely diffused. This also varies greatly in various parts of the country. In some parts, as in Shansi, the seams of pure coal are of great thickness, as much as 30 feet or more, in others the beds are thin, and separated by layers of limestone and argillaceous strata. These conditions point to a general elevation of the ocean bed alternating with periods of subsequent depression. The Coal Measures are in turn overlain by sedimentary deposits of sandstone, shales, and conglomerates, to a depth of many thousand feet. A general elevation then took place probably soon after the close of the Carboniferous epoch, and there is no evidence to point to any subsequent depression beneath the level of the sea. The Jurassic and Cretaceous series of rocks do not appear to be represented in China. The dominant feature in the geography of China is the existence of the enormous mountain masses on which her western frontier abuts. From these main ranges, spurs or outliers run into China, having generally an east or west trend, and these have determined the courses of the great rivers. Having their sources at a great height, and draining very extensive basins, these rivers have for ages been bringing down quantities of silt which have been deposited on the beds of ancient lakes, and on the sea bottom, thus forming the
Great Plain of China, which is now so large and important a part of the empire. It fills an area of about 200,000 square miles, and is still growing. Denudation has thus been the principal agency in giving to Chinese scenery its characteristic features. In Hunan and in Szechuen, where a soft red sandstone abounds, it has converted what at one time was probably a uniform plateau into a thoroughly hilly country. Although large masses of eruptive granite and other igneous rocks are to be found in various parts, it does not appear that volcanic energy has for many ages had any part in determining the configuration of the country. There is no trace anywhere of recent active volcanoes. Intrusive dykes of granite, porphyry, &c., are frequent, more especially in the northerly provinces and Shantung, and in a few places metamorphic action has altered the character of the rocks, but on the whole the sedimentary deposits have not been greatly disturbed by subterraneous activity. In the province of Shansi a plateau stands out above the plain where the several strata can be traced in a nearly horizontal position over a superficial area of 30,000 square miles. Looking from the plain westwards there is seen to be, first, a rugged barrier made up of very ancient formations ; second, a general substructure of limestone of 2000 feet in thickness; third, a series of coalbearing strata of 500 feet; fourth, the post-Carboniferous strata of 3000 feet; and, lastly, a general cover of loess. This is the largest coal field in China, and probably in the world, but a similar sequence of strata is found prevailing generally. Though no recent volcanic agency has been traced, there have been, subsequent to the limestone and carboniferous periods, very considerable upheavals, due either to subterranean forces or to the puckering consequent on lateral compression. The ridges thus thrown up have taken generally a north-east and south-west trend. They do not rise to any great height, seldom reaching 5000 feet, nor does any one ridge stand out as the predominant mountain chain, but the result is to give a general mountainous character to large areas of the country. One such belt of hills runs through all the south-eastern provinces from Tongking to Hangchow Bay, terminating in the rocky islands of the Chusan Archipelago. Another runs through Szechuen, and is cut transversely by the Yangtse river, which there flows between limestone cliffs forming the picturesque scenery of the Yangtse gorges. A third series starts from the Mongolian plateau and runs through Chihli and Shansi, forcing the Yellow river to take a long sweep southwards until it finds its way through a similar series of gorges at Lungmen. In the provinces of Kweichow and Yunnan the north-east and south-west system meets the outlying spurs of the central Asian system, which run nearly at right angles to the former, thus causing a confused mass of lofty mountain peaks which defies description. Along such ridges the limestone strata are tilted up and exposed to view, and in a few cases the still deeper strata of ancient plutonic rocks, granitic gneiss, and schists are also exposed. At one of the gorges in the Yangtse, where the river has cut its way across the ridge, the formation is well seen. There is, first, a central core of granite, then a thin bed of metamorphic schist, then the limestone inclined at a high angle on each side, then carboniferous strata, and, lastly, the superincumbent layer of sandstone and other recent deposits,—the latter, however, being often eaten away by erosion down to the limestone. This northeast south-west system, however, is on the whole subordinate to the dominant east and west ranges, stretching S. III. — 3
