L. Knopoff and J.N. Shapiro discuss the reelting of metals, and E.C. Robertson discusses the strength of rocks, D.L. Turcotte, Ithaca, N.Y.
E. Sherbon Hills, 1972. Elements of Structural Geology. Chapman and Hall, London, 502 pp., £3.75. This second edition of Professor Hills' well-known text is published both as a hardbound and as a paperback edition by Chapman and Hall Ltd. and Science Paperbacks. It contains 502 pages including indexes and illustrations on nearly every page. The first edition had three reprintings. The section on Structural Petrology which had been written by Professor E. den Tex in the first edition, has been revised by him (Chapter X II I ). After an introduction to the text called Domain and Contentof Structural Geology, the chief chapters are: Depositional Textures and Structures (43 pp.), Non-diastrophic Structures (29 pp.), Physics of Deformation (28 pp.), Environment, Time, and Material (37 pp.), Planar and Linear Structures and Jointing (21 pp.), Faults (52 pp.), Folds (45 pp.), Tectonic Analysis of Folds (34 pp.), Cleavage (25 pp.), Major Structures and Tectonics (36 pp.), Igneous Rocks (46 pp.), Structural Petrology (40 pp.), and Geomorphology and Structure - Morphotectonics (39 pp.). The chapter on Environment, etc. includes an appendix on Mohr diagrams. The numerous illustrations areclear, forceful, and appropriate, In the author's preface to the second edition he states that recasting of the first edition was not practical but that certain sections were rewritten, others expanded to include new concepts, and references throughout were brought up to date. The timehonored basic course in Structural Geology must now be facing the same problem of other traditional courses, such as general physical geology, sedimentation, physiography, and petrology, namely burgeoning branches with new separate courses in each. Our problems are, what should be the basin
preparation in general geology and then in structural geology. How do we reduce repetition? Fifteen years ago the subject of geosynclines was taught in at least a half dozen courses in the same department, and now the subject of plate tectonics is even more widely expounded. The wrestle with expansion in knowledge and changing emphasis is the ever-changing process of curriculum revision. There is no recourse to the author of a text such as the present one buttoexpand, otherwise too many professors who may use the book will be offended. A t the same time, these same users must eliminate some other parts. I think Professor Hill has done an admirable job in the above aspects of expansion and emphasis, but I must admit that if I were now teaching the course as a one-semester affair I would have trouble in covering the entire book. A.J. Eardley, Salt Lake City, Utah
J. Hailer, 1971. Geology of the East Greenland Caledonides. In: L.U. de Sitter (Editor), Regional Geology Series, Wiley-Interscience, Chichester, 413 pp., 158 fig., 117 photographs, £20.00. This volume is dedicated to Lauge Koch. Koch ranks as one of the true giants in the history of geological exploration and this su bstantial work of high quality is an appropriate memorial to him. Koch's field work spanned the years 1911-1958, covering most of the less accessible parts of Greenland in the north, west and east, but his most remarkable series of expeditions, entirely of his own devising, from the thirties onwards, concerned the area treated in this book. Hisvision, energy and enterprise overcame equally the practical difficulties of the polar environment and the scientific challenge of a large, complex, and relatively unknown region. He accomplished this exploration increasingly in later years by organisingwell-founded expeditions in which a changing team of international specialists was recruited, briefed, equipped and provided with the logistical backing necessary for a summer's or a year's work.