SUMATRA, siiro-mliqra. One of the Sunda Islands, the most western, also the largest, not reckoning Borneo, of the Dutch East India Isl ands, separated from the Malay Peninsula by the Malacca Strait, and from Java by the Sunda Strait (Map: East India Islands, B 5). It ex tends in a northwest and southeast direction. Its length is 1050 miles; its breadth ranges from 90 to 240 miles. Area, 161,612 square miles.
The Bukit-Barisan mountain range, of primi tive formation with a covering of eruptive rocks. lines the island along the whole western shore, and in the south and in the north diverges toward the east coast. The whole northern part of the island is in fact mountainous. The descent to the generally rocky shores on the west is eom paratively short and results in numerous valleys and ports of safety. To the east, in all the cen tral part, extend lower stretches of level and un dulating country sloping eastward, where all the main rivers are found, flowing eastward. often through marshy flats at the coast. The greatest elevations in the island are in the north, the loftiest peak being 12,100 feet. Here in the vicinity of Lake Toba—the most important lake —are steppes averaging 4000 feet in elevation. and thinly wooded, but the contiguous lower plains are rich in forests and charaeterized by dry rice-fields. In the region next south arc en countered volcanoes and deep river valleys. Fur ther south, in the large middle belt of the island, are also volcanoes on the west, rising to about 10.000 feet. Mere are Lake Alaninju, covering nearly 50 square miles and oecuprimg the sunken cone of a volcano, and Lake Singkara, of equal area. Out of the latter issues the Ombilin River, coursing over a high plain of Eocene for mation, and rich in coal fields. This whole fer tile region in the western part is thiekly popu lated and forms the Padang section, at present the most valuable industrial and commereial part of Sumatra. The largo, more or less allu vial, and plentifully watered southern part of the island is little known. Sumatra has eight active volcanoes. The western coast with its rich soil, timber, and mines has been innell more favorable to development than the eastern. The main rivers are the flali, ,iambi,
lndragiri, and !iaup:rr. They are of little im portance for navigation. Around a large part of the coast extend rows and groups of islands of more or less significance and once a portion of the mainland—Banka. Linga, Rupert, Simalu, Siberut, etc. As a whole, Sumatra geologically belongs to the neighboring continental regions; sandstone, limestone, and slate formations abound.
The equator passes nearly through the centre of the island; accordingly the even temperature is constantly high. the mean annual tempera ture ranging from 77* to SI° F. The animal rainfall varies from approximately 90 to 185 inches. The tower sections of the island are unhealthful, the higher are pleasant and habitable. Thunderstorms and waterspouts occur frequently, and earthquakes now and then. The flora is practically that of the Malay Penin sula and Borneo, containing a few remarkable special features, such as gigantic forms of arum. A large part of the island is overgrown with trees and foliage. The mountains are rich in tali timber. Oak, camphor. and teak trees abound. Sumatra is unsurpassed for fauna, nearly all the large equatorial types being present. Buffaloes are the leading live stock. The rhinoceros, ele phant, tiger, tapir, panther, deer, and many species of the ape are also largely represented. The supply of minerals is large. The island yields coal abundantly, and large tin deposits on Singkap Island on the east coast are being worked. Petroleum wells flow in the Palembang region, and there is an important output of pe troleum in Langkat.
Agriculture is the occupation of the natives. All the tropical crops are or can he grown. The native princes and the Government farm out land to cultivators. The natives skillfully manu facture filigree articles in gold and silver, fabrics, and household articles. The northeast coast. around Dili, is a rich and extensive tobacco country, which produced in 1899 about 53.000.000 pounds of tobacco. The pepper trade is impor taut. Coffee. bamboo, rubber, copra, and gums are also exported.