Page:The origin of continents and oceans - Wegener, tr. Skerl - 1924.djvu/182

156 interesting circumstance from the Sunda Islands: of the two most southern chains of islands, only the simply curved northern one bears volcanoes, not the southernmost (including Timor), which has already been curved in a reverse direction by collision with the Australian shelf. But at one place, near Wetter, the northern chain is already slightly bent because the southern one (north-eastern end of Timor) presses against it in that region; exactly at this spot on the northern chain there is vulcanicity, formerly of an active character, now obviously dying out because the curving is diminishing. Brouwer also draws attention to the fact that elevated coral reefs only occur where vulcanicity is absent or is dead, which likewise points to the fact that these areas suffer compression. The at first sight paradoxical result, that vulcanicity ceases where compression begins, finds a natural explanation within the compass of our ideas.