Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/524

 Mongolia in the north, and from Anhwei on the east to an unknown distance west, in all probability far into Central Asia. It rises in portions, as in Shansi and Mongolia, to a height of about 6000 feet over the present sea-level, forming at that elevation a deposit upwards of 1000 feet deep. At its southern extremity, in Kiangsu, it does not at present rise more than about 200 feet, though apparent fragments in the sides of the hills rise possibly to 400 feet. Over the raised plain of Anhwei it has been greatly denuded, and probably to a considerable extent rearranged. We must therefore believe in a general depression of Eastern Asia, at least from the latitude of 30° to 45° north and from 90° to 120° east longitude. This, however, is not all : South China, though probably never entirely submerged during the Tertiary epoch, shows in its valleys some traces of marine deposits of that age. Cambodia and Siam, as well as Birmah, with their fossil forests and beds of animal remains, have probably joined in the downward movement. The Sewalik hills, in India, seem to point to an elevation of some 6000 feet since the Miocene period. If Captain Montgomerie's pundit is to be believed, the plain of Lhasa, upwards of 11,000 feet over the sea-level, tells a similar tale. It may therefore be assumed that within the Tertiary epoch the whole of eastern Asia underwent a movement of depression and subsequent elevation. At the point of greatest depression, North China (except perhaps a few summits, such as the Ho-shan, in Shansi) was under the level of the sea ; South China formed a group of deeply indented islands, representing the ancient boundary-chains of the southern provinces. During the time of depression, while land was still near, the Luchow sandstones and Tertiary gravels were deposited ; afterwards, in the bed of a comparatively deep and tranquil sea, and at a distance from shore sufficient to have allowed all but the most impalpable particles to have already subsided, the Loess beds were thrown down.

Sufficiently startling, however, as is this induction, we can by no means stop there if we accept the premises. One of the most remarkable features in the geology of the chain of islands which bound on the west the great Pacific Ocean, is the enormous development of sandstones and coal-beds, accompanied with conglomerates of various sorts. Some of these beds, as at Takosima, near Nagasaki, in Japan, and at Apes' Hill, near Taiwan, in Formosa, are rich in fossil remains ; the coal-beds of Borneo are also known to have yielded characteristic fossils. Beginning, then, with Borneo, — stretching through the Philippine Islands, — continuing on through Formosa and probably the Loochoo Islands, — occurring again in Kiushiu, Nihon, and Yesso, in Japan, and extending as far as the coal-field of Dui, in Saghalien, we find a series of beds of sandstone, coal, and conglomerate agreeing generally in geological structure, and yielding, at such distant spots as Borneo, Formosa, and Kiushiu, characteristic fossils of apparently Mid-Tertiary age.

If we accept the submergence theory for Eastern Asia during this period, we must look elsewhere than to the present continent for the supply of materials for these very extensive deposits, as well as for