Principles of Modern Technology. By Adrian C. Metissinos. Pp. 337. Cambridge University Press. 1990. Hardback f45.00, US $75.00; paperback f 17.50, us $29.95.

This book is the product of 15 years of lecturing to ‘upper classmen’ at the Universi- ty of Rochester, New York. The text is divided into four parts, each split in two. The first part begins with the properties of semi- conductors and then builds on this to circuits, computers, and information storage.

The second part deals with the transmis- sion of signals (the principles of Fourier transforms are covered at a fast clip, in all of 5 pages). This leads to the generation and propagation of electromagnetic waves (wave guides and Maxwell’s equations feature prominently) directional antennae, satellite communications, fibre optics, and lasers.

The third part covers nuclear energy fun- damentals: binding, fission, fusion, nuclear reactors, radioactivity, and solar energy. Nuclear weapons follow with subsequent dis- sertations on fission and fusion explosives, delivery systems, reconnaissance satellites, and even arms limitation treaties.

The final part is, to me the most interest- ing: space travel, fluid flow, flight dynamics, supersonic flight, propulsion dynamics, and rocket engine principles. This section ends with the solar system, transfer orbits, inter- stellar travel, and finally inertial guidance, which is what we need after this tour de force.

The author has succeeded in compiling a useful book of teaching exercises and case studies, demonstrating the application of physical principles. For undertaking this daunting task, he is to be commended. In- spiration for teachers can be found therein.

A. Porteous

Topics in Remote Sensing 1. Physical Principles of Remote Sensing. By W. G. Rees. Pp. 247. Cambridge University Press. 1997. Hardback f35.00, US $65.00; paperback f 13.95, US $24.95.

Many books on remote sensing are aimed at environmental scientists. Rees’s book is writ- ten for physical scientists who need to know ’ . not only what remote sensing systems do, but how they work. .‘. The reader is expected to have a reasonable background in physics and mathematics; since the book draws on lectures delivered at the Scott Polar Research Institute and the Cavendish Laboratory, Cambridge, this is not surpris- ing. Ten chapters cover basics (electro- magnetic radiation and its interactions with surface and atmosphere); remote sensing systems (photographic, electro-optical and microwave); platforms; and data processing.

The introductory chapters are comprehen- sive, yet not at too high a level. Much of the material can be found elsewhere though not in such an accessible form. References to more comprehensive treatments are not numerous, making it difficult to follow up particular topics. Coverage of passive and active microwave systems is excellent, and

Exercises in Practical Astronomy using Photographs: with Solutions. Foreword by Owen Gingerich. By M. T. Briick. Pp. 108. Adam Hilger, Bristol. 1990. f18.50.

Astronomy is both an observational as well as a theoretical science, but the objects of its study cannot readily be brought into the laboratory. Yet the records - the raw mate- rial of observations - can, especially since professional observations are made using photography or electronic devices. For stu- dents, practical work utilising photographic evidence is an excellent substitute for observ-

will provide a valuable first source for those interested in the next generation of Earth satellites typified by ERS-1. In the final two chapters a very readable summary of orbital mechanics precedes a rather brief review of data processing which is of doubtful value. Each chapter ends with a set of problems (answers not provided). Overall, this is a welcome addition to the literature and, given its physical science slant, will become a stan- dard source of reference for students from these disciplines at both undergraduate and M.Sc. levels.

Paul Mather

An Introduction to Seismological Research. History and Development. By Benjamin F. Howell, Jr. Pp. 193. Cambridge University Press. 7990. f25.00, us $39.50.

My worry at seeing ‘Mythology’ as the first Contents entry proved to be unfounded. I enjoyed reading this book and learnt a lot. It is not a heavyweight, but a competent review of major developments within earthquake seismology. Simple explanations of key topics are interspersed with history, making easy reading for a wide audience. In Chapter 2, Cause of Earthquakes, the role of pore pressure is an example. However, explana- tion of other terms is conspicuously absent: e.g. Coulomb fracture (p. 13) and centroid moment tensor (p. 53). In Chapter 3, Seis- micity and the Prediction of Earthquakes, the author has (wisely?) considered predic- tion only briefly. The relationship between seismicity and plate tectonics are aired. and a diagram from Holmes reminds us how old some of the ideas are. The chapter on Instru- ments dwells rather on the ancient, neglect- ing seismometer arrays and broad band se- ismometers. Other chapters describe what has been learned about earthquakes and Earth structure from seismograms; mic- roseismic noise and tsunami are also co- vered. There is some repetition, e.g. seismic moment appears on pages 20 and 109, and the choice of references is sometimes rather arbitrary.

I recommend this book to anyone with a general interest, and as worthy background to students and researchers. Stuck in my mind is the author’s assertion at the end of Chapter 3: it is ‘virtually inconceivable’ that major earthquakes could not be predicted. I wonder!

R. G. Pearce

have had an unfortunate influence on the price of the book. To encourage more people to take cognizance of the important subject of stellar classification would have been achieved much mare readily with a price-tag nearer f10.00.

Mart de Groot

Wanderers in Space; Exploration and Discovery in the Solar System. By Kenneth R. Lang and Charles A. Whitney. Pp. 316. Cambridge University Press. 7991. Hardback f35.000, US $54.50; paperback f 15.95, US $24.95.

Our knowledge of the planets of our solar system and their accompanying moons, together with those other wanderers, comets

ing on cloudy nights, and at other times as well for that matter.

Dr Mary Briick has here collected together a number of interesting practical exercises. using photographs ranging from those of the Sun to others probing distant clusters of galaxies. In each case the evidence is given, and questions are posed - questions which raise fundamental points in astronomy and which the observational astronomer will need to ask. What is more, Dr Briick gives suggestions about how to obtain answers. and also provides the answers themselves.

This will be a mine of useful information to teachers of astronomy who will, surely, bless Dr Briick for her carefully compiled series of exercises. Serious amateur astronomers also should be made aware of a book which will surely delight them with its problems to while away nights when the sky is overcast.

Colin A. Ronatl

The Classification of Stars. By Carlos Jaschek and Mercedes Jaschek. Pp. 413. Cambridge University Press. 7990. fl7.50, US $32.50.

This is a guide to, and an exposition of, the results of the classification of stars by a pair of experts in the field. While it may seem rather dull reading to those accustomed to instant observational results on computer terminals, this book (although not necessari- ly all of it) should be read by all who use some classification scheme. It is, therefore, to be applauded that this soft-cover edition of the original 1987 hard-cover comes at a reduced price.

The book is announced as ‘reprinted with corrections’. In fact, it is more ‘reprinted than ‘corrections’. The latter have been li- mited almost exclusively to anglicizing (read: americanizing) the original text, which bore many marks of the fact that French is the language more familiar to the authors. Since the tirst edition was very readable already I wonder why this revision was necessary.

Just one nuisance: The luminosity class is printed in small capitals, like A2 v, whereas I would have preferred A2 V as in the older literature. And one question: Has there been so little progress in this subject that in the three years between 1987 and 1990 nothing worth mentioning has happened?

Resetting the type on most pages must

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