Magnetic interactions in solids. (International series of monographs on physics) by H. J. Zeiger and G. W. Pratt

in August, 1971. This was a sequel to the 1962 Scottish Universities' Summer School on Polarons and Excitions'. The lectures in this book are intended to cover the major theoretical and experimental developments in the polaron field in the intervening period, 1962-1971. The overall bias is to the theoretical formulations. The theoretical articles are detailed and reveal a continuing preoccupation with the technical details of the various rival formalisms. There is a particularly useful in-depth treatment of optical absorption and cyclotron resonance properties of free Fr6hlich polarons. There are also a number of interesting, well written experimental studies including polaron infrared absorption in the silver and alkali halides and a detailed review of the transport properties of strongly ionic crystals. The book does present a comprehensive picture of the state of play in relation to the polaron and, as always with such collections of lectures, there is something for everyone. The book as a whole will be invaluable to the expert or the would-be expert. The interested non-specialist should dip into the book. He will undoubtedly find something to interest him. If he wishes to obtain an overall view of the field, he must go elsewhere. A. W. B. TAYLOR Department of Theoretical Physics Chadwick Laboratory University of Lit'erpool P. O. Box 147 Liverpool L69 3BX England