Volume 14 Australasia - dana ward's homepage

162 AUSTRALASIA.crater, is encircled bj' a diadem of lofty peaks, such as the Rami (11,00U feet) onthe south-west, Kendeng on the north-west, Kukusan on the north-east, Merapiand others on the south-east, often collectively known as the Gunong Ijeu, or"Isolated Mountain." The waters that collect on this plateau were formerlyconfined in a lacustrine basin, but now escape northwards through a gorgebetween Kendeng and Kukusan.The crater of Rann at the time of Jungbuhn'svisit had a circuit of about three miles and a depth of no less than 2,400 feet,being the deepest of any yet explored in Java. But all these encircling volcanoesare now extinct or quiescent except Merapi, whose crater, like that of Kelut, isflooded by a freshwater lake, which, during eruptions, is changed to steam andprecipitated in the same way on the surrounding district. During the outburst of1817, houses and inhabitants were swept awaj', and the strait flowing betweenJava and Bali contracted by the formation of new land. The south-eastern' headlandof Java, formerly an island, has thus been joined to the mainland by showersof scoriae, while the extinct Baluran (4,300 feet), at the north-east extremity, isseparated only by a sill 50 feet high from the Gunong Ijen system.The island of Madura, close to the north coast, has a somewhat irregularsurface of limestone rocks, the highest of which, Tambuku, at the east end, has anelevation of little over 1,500 feet. As in Java itself, Yerbeek's .survey shows thatin Madura there is no trace of triassic, Jurassic, or chalk formations.Although the igneous are far less extensive than the sedimentary rocks in Java,this island receives its characteristic aspect from its forty-five conspicuous volcanoeswith their lateral cones, lavas, and scoriae. As the mariner approaches its shores,his gaze is irresistibly attracted by theselofty symmetrical cones, towering abovethe wooded plains, now purpled in the solar rays, now of a jmle blue, standing outagainst the deeper azure of the sky, at times surmounted by a wreath of whitevapours, at sunset flushed with pink like the snowy Alpine peaks. At differentepochs, but especially during later tertiary times, all these burning mountainshave taken part in the transformation of the island ; even during the historicp^iod more than twenty of them have contributed greatly to modify the profileand contours of the land, transforming what was before a chain of separateislands, like the Lesser Sundas, into one continuous insular mass stretching from]5ali to Sumatra. This action of the underground agencies appears also to havebeen aided by a process of slow upheaval, which is still going on ;in many places,the beach and coral reefs have thus been I'aised twenty, thirty, and even fifty feetabove the present sea-level.^RivEKs OF Java.Owing to the position of the volcanic ranges, lying for the most part muchnearer to the Indian Ocean than to the inland seas, the northern are far moreextensive than the southern fluvial basins, scarcely any of which are navigable.The north-western plains about Batavia are watered by numerous streams, thelargest of which is the Tarum, which rises on the slopes of the southern volcanoes,