PREANGER, a district in the south-west of Java, Dutch East Indies, including the Preanger Regencies. Formerly one residency, it has been divided into three—West Preanger, Middle Preanger and East Preanger, all of which are under the govern ment of West Java. They are bounded north by Buitenzorg, Kra wang, Indromayu and Cheribon, west by Bantam, east by Banju mas and south by the Indian Ocean. Pop.: West Preanger, 983, 632, Middle Preanger 1,298,025 and East Preanger, 1,731,365. The natives are Sundanese. The whole district is mountainous, and contains a large number of both active and inactive volcanoes, including the well-known Salak and Gedeh in the north, and bunched together at the eastern end the Chikorai, Papandayan, Wayang, Malabar, Guntur, etc., ranging from 6,000 to io,000 f t. The greatest rivers are the Chi Manuk and the Chi Tarum, both rising in the eastern end of the province and flowing north east and north-west respectively to the Java Sea, and the Chi Tandui, flowing south-east to the Indian Ocean. Crater lakes are Telaga (lake) Budas, in the crater of the volcano of the same name in the south-east, and Telaga Warna, on the slopes of the Gedeh, famous for its beautiful tinting. There are also other small lakes—Bagendit, Leles, Penjalee, etc. On the side of the Gedeh is the health resort of Sindanglaya (3,500 ft.), with a mineral spring containing salt.
Numerous warm springs are scattered about this volcanic region. Petroleum and coal have been worked, and there is a rich yield of chalk, while a good quality of bricks is made from the red clay. The soil is in general very fertile, the principal products being rice, maize, cassava and pulse (kachang) and rubber in the lower grounds, and cinchona, coffee and tea, as well as cocoa, coca, tobacco and fibrous plants in the hills. The coffee cultivation has, however, diminished considerably. Irrigation works have been carried out in various parts. The principal towns are Bandung, (q.v.), the capital of Middle Preanger, Sukabumi, capital of West Preanger, Tasik Malaya, capital of East Preanger, and Chianjur Sumedang, Chibatu, Chichalengka, Garut (q.v.), and Manon Java,
all with the exception of Sumedang connected by railway. The Preanger became Dutch in 1704, after the trouble with Susuhunan, Amangku Rat II. From the time of the British reform of the administration in Java by Sir Stamford Raffles (1811-16), it was known generally as the Preanger Regencies.
Pre-Cambrian and Archaean, in geol ogy, are used synonymously by certain authors and are so em ployed in this article. The term Archaean, however, is often used in a restricted sense to include only the oldest rocks, the Kee watin and Laurentian, for example, in North America.
The pre-Cambrian rocks are believed to underlie everywhere the Palaeozoic and all later formations ; and wherever erosion has penetrated deeply enough the pre-Cambrian formations have been brought to light. They are the most ancient of any exposed on the crust of the earth, and may have required more than half of all geological time for their formation. Their age can be only approximately estimated, the estimate varying within wide range —48,000,000 to 1,710,000,000 years. These venerable formations, which are now exposed over one-fifth of the land surface of the earth, consist dominantly of granitic rocks, massive gneissoid, or banded in texture. Sediments and lava flows, while occurring in great thickness in some regions, are subordinate. In many parts of the world the rocks have been tremendously altered. and now sediments, of which the Cobalt series at Cobalt, Ontario, forms a part. These sediments rest in horizontal or gently inclined posi tions, and differ in this respect from the closely folded Timis kamian. The unconformity at the base of the Cobalt series is, like that at the base of the Timiskamian, very great.