Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/842

816 816 same time the character of the scenery varies from island to island and even from district to district. The mountains arrange themselves for the most part in lines running either from north-west to south-east or from west to east. In Sumatra and in the islands between Sumatra and Borneo the former direction is very distinctly marked, and the latter is equally noticeable in Java and the other southern islands. The mountains of Borneo rise rather in short ridges and clusters from the plain, like islands from the sea ; the arrangement represented on even what are considered authoritative maps being, like much else in the cartography of the archipelago, the product of imagination. Nothing in the general physiognomy of the islands is more remarkable than the number and distribution of the volcanoes, active or extinct. 1 Running south-east through Sumatra, east through Java and the southern islands to Timor, curving north through the Moluccas, and again north from the end of Celebes through the whole line of the Philippines, they form as it were the rirn of a great atoll (to use Dr Schneider s phraseology), rudely resembling a horseshoe narrowed towards the point. The loftiest mountain in the archipelago would appear to be the famous Kina Balu in Borneo ; the loftiest of the volcanic peaks are Indrapura in Sumatra (12,255 feet), Semeru in Java (12,238), Gunong Agong in Bali (11,726), and Tamboro in Sumbawa (9324 feet). An important fact in the physical geography of the archipelago is that Java, Bali, Sumatra, and Borneo, and the lesser islands between them and the Asiatic mainland, all rest on a great submerged bank, nowhere more than 100 fathoms below the surface of the sea, which may be considered a continuation of the continent ; while to the east the depth of the sea has been found at various places to be from 1000 to 2500 fathoms. As the value of this fact has been particularly emphasized by Mr Wallace, the limit of the shallow water, which passes through between Bali and Lombok, and strikes north to the east of Borneo, has rightly received the name of Wallace s line. The Philippines, on the other hand, &quot; are almost surrounded by deep sea, but are connected with Borneo by means of two narrow submarine banks.&quot; 2 Geology. The geology of the archipelago has not been investigated even with the completeness attained in regard to the zoology and botany ; but there is a very considerable collection of material in the publications of the mining engineers of the Dutch Government (Jaarboek Mijnwezen Ned, 0. Ltd.); and for the Philippines a valuable &quot; Memoria geologico- minera &quot; has been printed in the Boletino of the Commission of the Geological Map of Spain (Madrid, 1876). The results obtained by the Dutch engineers have been summarized by Dr Schneider, &quot; Geologische Uebersicht iiber den holland.-ostind. Archipel,&quot; in Jahrbuck d. K.K. Geolog. Reichsanstalt, Vienna, 1876, Bd. xxvi. There is a wide and varied representation of the azoic formations gneiss, mica -schist, hornblende, &c., in Timor (which it may be remarked is geologically one of the best known of the islands), Ceram, Billiton, Banka, &c. Silurian rocks are found in Banka (where they contain the famous tin-mines), Billiton, and the Linga and Riouw archipelago; car boniferous limestone occurs in the north of Timor; the coal of Batchian is apparently similar to that of the English Carboniferous measures ; and the Coal-measures of Borneo are thought by Van Dyk to be also Palteozoic. The Sumatran coal is of unascertained age. Permian rocks are present in Timor, Celebes, Pulo-Laut, and Sumatra. Of Secondary formations we find both Triassic and Jurassic 1 A valuable list of these will be found in Junghulin s Java, a work which contains many details in regard to various parts of the archi pelago. 2 Wallace, Island Life, 1880. rocks, the latter represented by Oolites in Timor, by a coralline limestone in Celebes. Cretaceous rocks occur in both these islands and in Celebes. Throughout the whole archipelago the Tertiary formations have a wide develop ment both in their Eocene and their Miocene divisions. The latter is represented by foraminiferous limestone, and the former by nummulitic limestone. Lignite is freely distributed throughout the Tertiary strata of Java, Sumatra, and Nias. Among the rocks of economic importance may be mentioned granite of numerous kinds, syenite, serpentine, porphyry, marble (at least in southern Java), sandstones, and marls. Coal is worked successfully in Sumatra, Borneo, and Labuan. Diamonds are obtained in Borneo, garnets in Sumatra, Batchian, and Timor, and topazes in Batchian; antimony in Borneo and the Philippines ; lead in Sumatra, Banka, Flores, and the Philippines ; and copper and malachite in the Philippines, Timor, Borneo, and Sumatra. Iron is pretty frequent in various forms, and in some places might be successfully worked. Gold is not uncommon in the older ranges of Sumatra, Banka, Celebes, Batchian, Timor, and Borneo. Manganese could be readily worked in Timor, where it lies in the carboniferous limestone. Platinum is found in Landak and other parts of Borneo, and mercury in small quantities in Java. The meteorology of the archipelago has hitherto been Met ; studied only in a very vague manner. For Batavia, in- ^ST deed, there exists a mass of observations ; and the observa tory there is extending the region of its investigations. At the close of 1879 it had one hundred and twenty-five rainfall stations. A magnetic survey of the islands has been made by E. Van Rijckevorsel, whose report is pub lished by the Academy of Sciences of Amsterdam. The most striking general fact is that, wherever that part of the south-east monsoon which has passed over Australia strikes, the climate is comparatively dry, and the vegeta tion is less luxuriant and luscious. The east end of Java, e.g., has a less rainfall than the west ; the distribution of the rain on the north coast is quite different from that on the south, and a similar difference is observed between the east and the west of Celebes. According to Dr Bergsma s Rainfall of the East Indian Archipelago, First Year, 1879 (which, like other publications of the Batavian meteorological office, is printed in English), at thirty-three stations out of fifty-nine the annual rainfall exceeded 100 inches, and at five stations .200 inches. The highest regis tration was 282 inches, at Padang Pandjang (Sumatra). The north-west monsoon, beginning in October and lasting till March, brings the principal rain season in the archi pelago. The midday heat of the sun, it need hardly be said, makes itself powerfully felt. Exposure to its direct rays in Timor, for example, &quot; at any time between 9 A.M. and 3 P.M.,&quot; says Mr Wallace (Tropical Nature), &quot;would blister the skin in a few minutes almost as effectually as the application of scalding water,&quot; and Mr Moseley men tions that on wading into the sea at the Aru Islands he found the heat of the water actually greater than was at all pleasant. But at the same time the general climate cannot be said to be oppressive or unhealthy. Most of the islands of the archipelago belong to that Vege great forest-belt which, in the words of Mr Wallace, tion&amp;gt; &quot; girdles the earth at the equator, clothing hill, plain, and mountain with an evergreen mantle.&quot; In islands and districts where human civilization has been at work for centuries, the natural covering has in large measure given place to artificial tilth ; and in Timor and several of the south-eastern islands the characteristics of New Guinea luxuriant herbage and open park-like wood lands are more or less strikingly predominant, 3 The 3 Wallace, Malay Archipelago, p. 8.