BOOK REVIEWS ous DTA and gas analysis is covered in the chapter on pyrolytic techniques, not in the earlier chapters on DTA. However, when one considers the magnitude of the task, such criticism would he trivial. The temiuetion of the DTA reaction is assumed to occur a t the peak apex (p. 133) and Vold'a work is cited (p. 170) showing the termination well beyond the apex. No explanation is offered for this discrepancy. Kissinger's approach to reaction kinetics is included. However, only recently (1965) has it been shown to he in error. In general, the technical content of the book is very good. The clarity of presentation would make the book useful in the hands of both student and professor and both established researcher and neophyte. To the reviewer's knowledge, it is the first attempt to compile a comprehensive discussion of the major methods of thermal analysis in one volume. Aa such, it will permit more logical decisions to he made with regard to technical approaches to problems and with respect to instrumentation to he applied. C . B.MURPEY Aduaneed Technology Labmatories General Electric Cmnpany Sehaectady, New York Crystals: Science
Their Role in Nature and in
Charles Bunn, Royal Institution, London. Academic Press, Inc., New York, 286 pp. Figs. and ta1964. viii bles. 13.5 X 20.5 em. Paperbound, $3.45; cloth, $6.50.
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What is a crystal? Why does it exist and how was it formed? What symmetries may it have and how do they affect its external ahape? How does one understand its peculiar optical properties? Charles Bunn answers these questions in a delightful hook which makes few a+ sumptions of specialized knowledge or mathematical facility. Hardly a math* matical formula amears in the book.
reader understand the discussion. One may suspect that this format would lead to a superficial and inaccurate a* count. On the contrary, the simplification is a t the expense of remarkably little rieor. "Crvstals" is recommended as a n introduction to crystallography for the non-specialist who wants a general view of that field. I t is also recommended as a supplementary reading for the college freshman or for the graduate student in crystallography before he gets involved in the mathematical details. I t should be required reading for the author who is about to write a popultr account of hie special research field, or the specialist who denies that his research can he discussed usefully without mathematical jargon.
DAVID H. TEMPLETON University of California Be~kelq
A550
/
Journal of Chemical Education
