BOOK REVIEWS

The book is divided into five main hydromagnetics and the interaction of The anatomy sections covering the physics of the solar large- and small-scale systems. Indeed, interior, including convection theory, the basic mechanisms underlying flares, of the Sun structural modelling and dynamo theory; the heating of the corona and the solar solar-oscillation observations and theory; wind, all involve solar magnetism at J. B. Zirker the structure of the solar surface; solar many spatial and temporal scales. magnetic activity in all its guises; and the The authors present current observa­ Solar Interior and Atmosphere. Edited Sun as a star. tions without much discussion of the by A. N. Cox, W. C. Livingston and M. S. The chapters on helioseismology are instruments that made them possible. Matthews. University of Arizona Press: particularly enjoyable. This field is only This is something of a shortcoming, 1991. Pp. 1,416. $65, £57.95. Distri• about 15 years old and is developing into because there has been a revolution in buted by Eurospan in Europe. a marvellous tool for exploring the deep solid-state detectors, X-ray telescopes, interior of the Sun. The subject is ele­ imaging spectroscopy and computer OUR Sun proves the rule that the closer gant, both in its experimental and analysis of huge data sets. But even in a you look at anything in nature, the more theoretical aspects. More importantly, tome of this size, something has to be complicated it becomes. For at least 40 the study of oscillations is guiding omitted. years, astronomers have sought satisfac­ attempts to understand how the Sun For all our increased knowledge about tory explanations for some of the most generates magnetic fields and why the the Sun's behaviour, new questions keep obvious solar phenomena. Why does the solar cycle behaves as it does. popping up. Where are all the missing Sun's equator rotate faster than its One cannot fail to be struck by the neutrinos? How is the solar wind driven? poles? Why is its outer atmosphere so shift of emphasis that has occurred since There is, fortunately, no end to the incredibly hot? What causes its ll-year G. Kuiper's compendium The Sun was fascinations of this seemingly prosaic cycle of activity? What, exactly, is a published in 1953. At that time, radia­ ~H. 0 sunspot? How, indeed, does the Sun tive transfer, spectral-line analysis and generate the huge explosions that rattle nonthermodynamic equilibrium studies J. B. Zirker is at the National Solar the Earth's magnetic field? were at the cutting edge of research. Observatory, Sunspot, New Mexico During the past decade, dramatic Now the focus is on hydrodynamics, 88349, USA. progress has been made in answering these questions. We now have better equipment on the ground and in space, and a deeper knowledge of plasmas and Difficult superconductivity does Burns really believe that the topic elementary particles, coming in part A. C. Rose-Innes from the controlled fusion programme. of high-temperature superconductivity Solar problems now attract some of the involving highly anisotropic extreme best minds in astrophysics, and there is a High-Temperature Superconductivity: An type II superconductors, the understand­ growing realization that we have much Introduction. By Gerald Burns. ing of which is defeating established to learn from other stars similar to the Academic: 1992. Pp. 199. $19.95, experts in the field, is suitable for "stu­ Sun. Solar astronomy has grown to be­ £13. dents taking their first solid-state physics come solar physics, and new generations course"? of physicists have answered the call. GERALD Burns admits to having found For experts, by contrast, the informa­ All these developments have been ex­ this book difficult to write. I am not tion on high-temperature superconduc­ citing, but devilishly difficult to keep up surprised; it has been estimated that tors is diluted by presentations of with. At last, this blockbuster of a book 20,000 papers were published on high­ elementary superconductivity, even has appeared to summarize the subject temperature superconductivity in the though the author states that readers are and point the way to the future. It is one five years after its discovery. To read assumed to have this background know­ of two volumes on the Sun in the Uni­ their titles alone would probably take ledge already. versity of Arizona Press Space Science about 30 hours. Despite the inclusion of elementary Series*. Two years in the making, with Burns is surely over-optimistic when and sometimes irrelevant material, the an international cast of 101 authors and he says that there has been a "remark­ book provides a much needed review of around 1,400 pages, this monumental able rate of progress" in the study of the field up to 1991. It is to a large volume consists of a well-integrated col­ high-temperature superconductors; my extent a catalogue of often conflicting lection of topical reviews of many of the impression after reading this book is that experimental and theoretical results. principal aspects of solar phenomena. there is in fact still little understanding of In this respect, the summary sections Readers need a graduate'S competence these materials and few areas in which will prove to be particularly valuable. in physics and mathematics and a good they have been successfully applied. This No one can fully cover the vast amount grounding in solar observations. For the situation will probably persist until of literature on high-temperature super­ most part, the book is written clearly reasonably large single crystals are readi­ conductivity - I know workers who feel and scholarly, but not pedantically. Each ly available for experimentation. I am so overwhelmed that they have given chapter has an abstract and a summary. reminded of the similar confusion over up attempting to read the literature There is a useful glossary and a compre­ the properties of semiconductors in the at all. A review volume such as this hensive up-to-date list of references. A early 1950s before the advent of single will certainly be useful to them. Indeed, fine sense of the excitement of research crystals of germanium and silicon. every researcher in high-temperature comes through in several chapters, and, It is not clear to me for whom this superconductivity would benefit from understandably, there is a flavour of book is written. It is a curious mixture of obtaining a copy. 0 controversy, even contradiction. the very elementary, such as a basic introduction to perfect diamagnetism, A. C. Rose-Innes is emeritus professor of The companion volume is The Sun in Time * and of advanced concepts, such as a physics and electrical engineering in the edited by C. P. Sonett, M. S. Giampapa and M. S. Matthews, an interdisciplinary review detailed discussion of Ginzburg-Landau University of Manchester Institute of Sci• of the Sun's evolution written by 83 collabor• theory. But it is not really suitable for ence and Technology, PO Box 88, Man• ating authors. $60. novices such as undergraduates. Indeed, chester M60 lQD, UK. 552 NATURE· VOL357 . 18JUNE1992

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