Die vulkanischen Erscheinungen der Erde

Abstract

DR. SCHNEIDER opens his work by reference to what is found in many books on vulcanology and geology, namely, the part played by volcanic activities in the economy of nature. In consequence of volcanic action minerals of high specific gravity are brought to the surface, the contours between land and water may be changed, and new islands may be created. Since Tertiary times 3.96 mill, km.² of land surfaces have been covered by volcanic ejecta. These accumulations have altered relative altitudes, on which climate, plant life, and other things depend. Valleys have been blocked, lakes formed, and river courses have been changed. At the time of an eruption a variety of gases and chemical products are brought to the surface, and many mineral deposits are closely associated with volcanic action. Although in many ways volcanoes have been beneficial to humanity, in their immediate vicinity they have been frequently associated with the loss of life and property. Volcanic explosions have excited the imagination, given rise to myths concerning subterranean deities or monsters, and indirectly have had an effect on literature and art.

Die vulkanischen Erscheinungen der Erde.

By Dr. K. Schneider. Pp. viii + 272. (Berlin: Gebrder Borntraeger, 1911.) Price 12 marks.