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The Geology of South Australia. Walter Howchin

1919 The Journal of geology  
The Geology of South Australia. BY WALTER HOWCHIN. Pp. xvi +543. Figs. 330 and geological map. Adelaide: Government Printer, 1918. Hitherto there has been no book which treated geologic processes and the general principles of geology from the Australian standpoint, although The Geology of New South Wales by Siissmilch may be cited as an admirable text on the historical geology of that interesting state. A feeling that there was need for a work on general geology with illustrations drawn from
more » ... tions drawn from Australia has led to the present volume. This volume is in two divisions. The first portion, which makes up more than half of the book, deals with geologic processes, the materials of the earth, and dynamic principles; the second portion outlines the historical geology of South Australia. While limited space precludes an exhaustive treatment of geologic principles, the reader nevertheless finds a great deal of well-illustrated material within these pages. The examples, illustrations, and concrete facts, taken largely from the Australian continent, come with a special freshness to the geologist of the Northern Hemisphere, to whom they are largely new and decidedly welcome. A few points of dissent may be noted. The author's classification of the different forms of glacial deposits is perhaps not altogether orthodox from the viewpoint of others, as may be illustrated by the following statement, which appears under the heading of "Unstratified Glacial Deposits," on pages 146-47: "Subglacial streams wear irregular channels through the ground moraines, and when the ice disappears irregular ridges or mounds of drift are scattered over the valley bottom and are known as eskers, in Iceland; kames, in Scotland; osars, in Sweden; and drumlins, in America." On page 215, below a diagram illustrating slaty cleavage in a much-folded section, the statement is made that "cleavage planes preserve an exact parallelism and identical strike over wide areas, and are independent of the foldings of the rock as well as the bedding planes." Instead of being independent of the folding, flow cleavage has recently been shown to be developed parallel 39I This content downloaded from 154.059.124.
doi:10.1086/622668 fatcat:v6apnipzqzf2jjwiizatr52qnu