Die Entstehung der Kontinente

WEGENER, Alfred

Published by Justus Perthes, Gotha, 1912

About this Item

CONTINENTAL DRIFT. First edition, journal issues in the original printed wrappers. "Wegener is remembered today as the originator and one of the chief proponents of the theory of continental drift, which he conceived after being struck by the apparent correspondence in the shapes of the coastlines on the west and east sides of the Atlantic, and supported with extensive research on the geological and paleontological correspondences between the two sides. He postulated that 200 million years ago there existed a supercontinent ( Pangaea ), which began to break up during the Mesozoic era due to the cumulative effects of the Eötvös force, which drives continents towards the equator, and the tidal attraction of the sun and moon, which drags the earth s crust westward with respect to its interior. Wegener s drift mechanism was later shown to be untenable; it has been replaced by the idea of convection currents in the earth s upper mantle. Wegener s first publication on continental drift appeared in three issues of Petermanns Mitteilung in April-June 1912; however, Wegener s theory attracted little interest until 1919, when he published the second edition of his treatise Die Entstehung der Kontinente und Ozeane. Between 1919 and 1928 continental drift was "the focus of much controversy and debate, but the theory afterwards fell into obscurity, not to be revived until the discovery of new paleomagnetic evidence in the 1950s" (Norman). Wegener (1880-1930) died at the early age of 50 on an arctic expedition at Eismitte in Greenland. ABPC/RBH record no copies of this important paper in the original printed wrappers since the Norman copy, which was rebacked (Christie s, 29 October 1998, lot 1337, $2185). Before Wegener put forward his revolutionary theory, it "was widely believed that continents and ocean basins are primordial features. This conviction was reinforced by global oceanographic surveys in 1872-77 demonstrating the Earth s bimodal elevation frequency, and simultaneously by gravimetric and geodetic surveys in the western U.S. and elsewhere that confirmed the principle of isostasy (i.e. an elastic crust that floats on a fluid medium). A continent can neither rise from the abyss or sink to abyssal depth spontaneously. The mass excess of its elevation is compensated by a mass deficit at depth. If it were to move sideways, it would have to drag its moorings along with it, which was thought to be absurd. Isostasy cut both ways however: it rendered physically implausible the land bridges invoked by geologists to account for ancient floral and faunal similarities between continents now far apart" (Hoffmann, The tooth of time: Alfred Wegener, Geoscience Canada 39 (2012), 102-111). Wegener s interest in the problem was awakened by two chance observations. "Wegener s office mate had received a world atlas with up-to-date bathymetric maps for Christmas in 1910. They noticed that the east coast of South America appears to fit against the west coast of Africa, "as if they had once been joined". The fit is even better, Wegener continued, if the tops of the respective continental slopes are matched instead of the present coastlines. "This is an idea I ll have to pursue", but he did nothing more with it until the Fall of 1911, when he "quite accidentally" came upon a treatise on continental paleogeography (strata, flora, fauna and climate), compiled by a German high-school teacher only two years older than himself. Here, Wegener learned of the remarkable similarities in Mesozoic flora and fauna between Brazil and Gabon, and also of the concept of sunken land bridges then widely invoked by geologists to account for such linkages. As a geophysicist interested in glaciology, he was more convinced than contemporary geologists that isostasy precludes land bridges from sinking to abyssal depth. When Wladimir Köppen gently advised him not to stray too far from what he knew, Wegener wrote back (in early December) that the geological linkages re. Seller Inventory # 4417

Bibliographic Details

Title: Die Entstehung der Kontinente

Publisher: Justus Perthes, Gotha

Publication Date: 1912

Binding: Hardcover

Edition: First edition.