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NAME

Letters

Dr. Perry also claims that I was wrong in referring to the lack of some basic discussions. For example, I men­tioned that the retention index is not explained, and his answer is that it is discussed in four pages. However, no­where is its meaning explained, that it corresponds to the carbon number (X 100) of a hypothetical η -paraffin with the same retention characteristics. Also, while the fundamental equation is treated in detail, the conclusions are not drawn. For example, in pp 43-53, the variation in liquid loading is dis­cussed historically but is not related at all to the last term of equation 4.8. If the capacity factor (k) is small, ways must be found to increase it, while if k is large, one tries to reduce it. Such a discussion is much more important than showing how equations are rear­ranged, moving a term from the right-hand side to the other or vice versa, which is elementary mathematics.

Dr. Perry complains that I did not mention some features that are "sin­gular to this book" such as an elabo­rate treatment of open tubular col­umns or of fused-silica columns. But these are self-evident in a general book on gas chromatography pub­lished in 1981. Would you praise a book dealing with basic mathematics because it also discusses multiplica­tion?

I could continue and present a re­buttal of each point in Dr. Perry's let­ter; however, I feel that this is unnec­essary. Rather, permit me to make a general statement.

A book review is not promotional material extolling the virtues of the particular book. Rather it represents the personal opinion of the reviewer who is selected by the editor of the journal because of his familiarity with the topics. Also, a review is not a sci­entific paper in which every statement must be explained and proven. The author may or may not agree with the reviewer. However, the author can be sure that the reviewer had good rea­sons for every statement in the review, even if he did not elaborate in detail; after all, only summary conclusions can be given in 500-600 words.

In my review of Dr. Perry's book I characterized it as a useful general text for GC training courses and ex­pressed my opinion that, in spite of a number of shortcomings, it fills many of the requirements for a serious, modern general textbook on gas chro­matography. There is nothing I can add to this opinion.

L. S. E t t r e Norwalk, Conn.

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424 A · ANALYTICAL CHEMISTRY, VOL. 54, NO. 3, MARCH 1982

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