128 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS of mixtures of undisclosed com- position. The use of three observers and the averaging of their results, would leave much to be desired from the statistical viewpoint. Among the stimulants for thought and study, one finds a statement by Stoll that nerol and geraniol have very different odor strengths, but their thresholds of perception are rather close. Having assumed, without question or challenge, that odor strength and threshold of perception are directly proportional, this statement offers a new vista for experiment. In fact, this entire book offers a broadened field for study. The facts so difficult to verify and correlate, the viewpoints so openly divergent, the searching and the groping, are healthy symp- toms of the struggle to forge a science ofolfaction. In this struggle the achievement of Naves trans- cends his work of analysis and synthesis (elucidation of the struc- ture of the irones and their synthetic reproduction), his incredible pro- lificacy, and his co-authorship of Natural Perfume Materials the great achievement of Naves is that he has brought rigorous and disci- plined scientific methodology into a field in which its absence was frequently distressing. This is a bilingual book, part of it being in French, which is rather curious in view of the fact that most of the papers published in English were probably delivered in French, German, or perhaps Dutch. Why one paper and fragments of the discussion were not translated, while the remaining parts of the book were rendered into English, is not explained. These are lengthy but minor exceptions to a book indispensable to those interested in olfaction.-- EDWARD SAGARIN, Embassy Lab- oratories. DIE XTHERISCH•.N 0LE, Volume I, by E. Gildemeister and F. Hoffmann Akademie Verlag, GmbH., Berlin W. 8, Germany. 1956. 500 pages, 61/,. X 91/2 inches, illustrated and indexed. Price33.50D.M. Volume IV, 720 pages, Price 55 D.M. It is twenty-five years since the earlier edition of this classical work has appeared. The work is brought up to date by Wilhelm Treibs. Volume I is a historical intro- duction, discussion of production in the most modern producing areas, possible uses and physiological prop- erties of essential oils. Volumes II and !II will discuss analytical methods. The remaining volumes of the set of seven will cover the individual essential oils. Volume IV deals with the oils derived from cryptogams, gym- nosperms, monocotyledons and part of the dicotyledons including moni- miaceal. The mon. o.graphs .fo. llow a uniform pattern g•v•ng ong•n, extraction, characteristics and composition among the principal properties of each oil. Some monographs dealing with the more commercially im- portant oils are much longer than others. The data appear adequate. When completed, these useful volumes will enrich the knowledge of the volatile oils.--M. G. I)E- NAVARRE. ORGANIC COLLOIDS, by Bruno Jirgensons. D. Van Nostrand Co., Inc., Princeton, N.J. 1958. 900 pages, 6 X 9 inches, illustrated and indexed. Price $16.75. The book is divided into two parts, a general description of methods of preparation with a study of organic colloids and a "systematic survey of the most important classes of molecular and miceliar colloids" in a condensed

BOOK REVIEWS 129 form. Indeed, the first 278 pages are a practical exposition of col- loidal behavior brought up to date. The title of this book is somewhat misleading. It is hoped it will not affect its use and sale. Indeed, one would think it a book on gums and closely related products. While it does include a brief discussion of a number of gums, this subject is only minor subject in the volume. Instead, colloidal phenomena in all its organic manifestations-- hormones, fibrous proteins, syn- thetic macromolecules (nylon), P- VP, emulsions, nucleic acids, starch and milk are samples of the wide range of subjects discussed. The author makes good use of illustrations and tables to elaborate his text. This is one of the most unusual and undoubtedly most useful books this reviewer has been privileged to read. It is recommended to all in this industry.--M. G. NAVARRE. ION EXCHANGERS IN ORGANIC AND BIOCHEMISTRY, edited by Calvin Calmon and T. R. E. Kressman. Interscience Publishers, Inc., New York 1, N.Y. 1957. 761 pages, size 61/4 X 91/4 inches, indexed and illustrated. Price $15.00. The importance of ion exchange phenomena and techniques in van- ous phases of biochemistry and or- ganic chemistry needs very little em- phasis. Living systems exhibit many, many ion exchange phenom- ena and investigators, studying the chemistry of such systems employ many ion exchange techniques in the course of their studies. The volume, "Ion Exchangers In Organic & Bio- chemistry," is therefore a most welcome addition to the literature. The editors of this book, Calmon and Kressman, experts in their own right, have assembled an impressive array of talent in their efforts to summarize the principles and practices of ion exchange in the fields of organic chemistry and biochemistry. The book is composed of three major sections. The first two parts deal with material of a general nature and the third deals with specific applications. Part 1 includes discussions on the nature and types of ion exchange materials, swelling and equilibria, kinetics and adsorption of non- electrolytes and chromatographic phenomena in columns. Part 2 deals with materials, techniques and apparatus, including commercial materials, simple pro- cedures, techniques of ion exchange chromatography, ion exclusion and mem branes. Part 3, the major portion of the book, deals with specific applications including bone as an ion exchange system, ion exchange properties of cells and tissues, bacteriology, vi- rology, separation ofamino acids and pe. ptides, chromatography of pro- te•ns and nucleic acids, nucleic acid derivatives, chromatographic investigations of non-steroid hor- mones, separation of carbohydrates, isolation and analysis of urine, application in blood, sodium-potas- sium removal in the body, gastric acidity, miscellaneous medical and pharmaceutical applications, ex- change adsorption in man, isolation and purification of antibiotics, vita- mins, alkaloids, ion exchangers of plant origin, ion exchange in plant physiology, purification of sugars and alcohols, treatment of alcoholic beverages and fYuit juices, milk and milk products, ion exchangers in organic chemistry, ion exchangers as catalysts and water treatment. The only criticism the reviewer has of this book is that some of the material contained in Part 1, 2 and