Book reviews GAS CHROMATOGRAPHY 1966. Editor: A. B. Littlewood. Pp. xii+ 464 q- Ill. (1966). Institute of Petroleum, London. 100s. This is a record of the proceedings of the Sixth Biennial International Sym- posium on Gas Chromatography and Associated Techniques organised by the Gas Chromatography Discussion Group, and held in Rome in September 1966. Gas chromatography is by now a mature, widely applicable but highly specialised technique. These proceedings rightly highlight selected recent advances and the appeal of the volume is therefore mainly to the specialist analyst and physical chemist rather than the more general reader seeking an up-to-date balanced account of gas chromatography. The main part of the book consists of the 25 formal papers that were presented, each with a summary. By now much of the material has appeared elsewhere in the literature but the book is justified by its collection together in one place of much valuable information and by the often revealing discussion that follows each paper. Gas chromatography has for long drawn heavily on established physico-chemical theory. It may now repay the debt by providing data for the physical chemist judging by three papers dealing with its application to studies on chemical equilibria, ther- modynamics of dilute solutions and hydrogen bond energies. Two new types of stationary phase are discussed. Graphitized thermal carbon black retains molecules largely in accordance with their planarity and can give some remarkable separations of terpenes. The well publicised microporous polymers yield some novel separations particularly of polar compounds. Two papers deal with improving column performance. Glass capillary columns are treated in one and liquid chromatographic columns in the other. The latter, envisaging separations comparable in speed and resolving power to gas chromato- graphy, is particularly relevant with recent innovations in liquid chromatographic detectors. Preparative glc is usually a batchwise process. Two contrasting practical designs of circular gas chromatograph demonstrate the possibility of a continuous separation. Three detectors are detailed. A modified flame-ionisation detector is specific for organosilicon compounds and a coupled flame-ionisation/sodium thermionic detector is specific for compounds containing halogen or phosphorus. The third detector, termed a reaction coulometer, works on a "feed-back" principle and claims calculable responses amongst its advantages. Probably the most significant amongst a group of papers on novel applications is one showing that the direct resolution of optical isomers on an optically active liquid phase need not be just a tantalising dream--excellent separations of pairs of enantiomers of certain amino acid derivatives were achieved. Another paper shows how this type of problem can be solved through conversion to diastereoisomers. Evaluation of heterocyclic nitrogen compounds in atmospheric dusts, ultra-trace 695

696 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS analysis of beryllium (down to 4 x 10 -'3 g) and analysis of metal chlorides are the remaining papers in this group--a group indicating the wide range of gas chromato- graphy when imaginatively applied. No technique is complete in itself. The direct coupling of a mass spectrometer to the exit of a gas chromatograph produces an analytical tool of immense power and this is duly treated in this volume. However, for most of us, this combination is on the wrong side of a financial barrier and the description of an apparatus that combines relatively cheap mass and ir spectrometers with glc by modifying the chromatographic technique ("interrupted elution") will be of more immediate interest. The use of digital computers to treat complex chromatographic data is exemplified in two papers. Isotope dilution techniques are shown to improve the accuracy of analysis of trace components and a type of zone refining in reverse is detailed as an excellent concentration procedure for volatile flavour compounds in dilute aqueous solution. The last formal paper presents the results of an interlaboratory correlation trial using a fatty acid ester/hydrocarbon mixture. It provides a salutary reminder after all that has gone before that some of the "simple" gas chromatographic problems have not yet been fully solved. The ten informal discussion sessions on topics ranging from commercial instru- ments to flavours and essential oils are reported in 39 pages and will repay a close and critical study. A list of delegates and good indexes complete a •vell-produced volume. R. N. BEVITT GAS CHROMATOGRAPHY ABSTRACTS- 1966. Editor: C. E. H. Knapman. Pp. xi+ 315 (1967). Institute of Petroleum. 63s. This hardy annual is welcome by all involved with gas chromatography, even those who have found it advantageous to join the Gas Chromatography Discussion Group of the Institute of Petroleum and receive the abstracts quarterly, and subsequently the annual volume at a reduced price. This is the ninth volume in the series and contains 1200 references (i.e. the contents of the four quarterly insraiments published in 1966) abstracted from a wide and comprehensive selection of journals. There has been a slight revision of subject index headings which is clearly explained under the heading of "Principles of Indexing" and this successfully aims to give a maximum number of cross references. The volumes of cumulative Indices for 1958- 1963 inclusive is now available. Tables of retention indices of solutes on squalene, dinonylphthalate and polyethylene glycol 400 are included for the first time. These tables are produced by the Data Subcommittee of Gas Chromatography and are a useful addition. Another new item is a trade name glossary of gas chromatographic materials and their chemical equivalents.The list is not exhaustive but it will be extended in due course and readers are asked to contribute where possible. In common with all abstracts there is an inevitable time delay but this volume is a very useful addition to every gas chromatographer's reference library. Its best features lie in its compact size, comprehensive cover of published work and an effective indexing system. Mrs. D. M. GABRIEL