CHAPTER IX

THE RISE OF MOLTEN ROCK TO THE EARTH’S SURFACE; VOLCANIC MOUNTAINS OF EXUDATION

Prevalent misconceptions about volcanoes—Early views concerning volcanic mountains—The birth of volcanoes—Active and extinct volcanoes—The earth’s volcano belts—Arrangement of volcanic vents along fissures, and especially at their intersections—The so-called fissure eruptions—The composition and the properties of lava—The three main types of volcanic mountain—The lava dome—The basaltic lava domes of Hawaii—Lava movements within the caldron of Kilauea—The draining of the lava caldrons—The outflow of the lava floods 94