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ing their nature. A very great frac­tion of the review is naturally on metal-liquid ammonia solutions, about which most is known, but there is also per­tinent reference to metal-amine and metal-ether solutions. After a brief consideration of solubilities and phase diagrams, the properties of dilute solu­tions, solutions of intermediate concen­tration, and concentrated solutions are taken up in turn. This reader, whose interest in nonaqueous solvents is pri­marily in their use as media for chemi­cal reactions, found the chapter most enlightening.

The final chapter in the book is an authoritative account of some aspects of inorganic chemistry in liquid am­monia, the solvent most extensively investigated by inorganic chemists. Topics discussed in some detail include structural considerations and physical properties, solvent purification, solu­bility relationships, electrochemical studies, reactions of the representative elements and their compounds, and re­actions of transition metal compounds.

Techniques of Organic Chemistry. Vol. XII. Thin-layer Chromatog­raphy. Justus G. Kirchner. xxi + 788 pages. John Wiley & Sons, 605 Third Ave., New York, Ν. Y. 10016. 1967. $21.95. Reviewed by Kurt Randerath, The

John Collins Warren Laboratories of the Huntington Memorial Hospital of Harvard University at the Massachu­setts General Hospital, Boston, Mass. 02114.

Justus G. Kirchner, whose pioneering work was published about 15 years ago in this Journal, first clearly demon­strated the scope and importance of the method now known as thin-layer chromatography (TLC). He now has written a comprehensive text on this method. The book covers the applica­tions of thin-layer chromatography and electrophoresis until the end of 1964, including a large par t of the literature published in 1965.

The first part (240 pages) gives, after a historical introduction (pp. 3-7), a detailed review of the general experi­mental procedures, including prepara­tion of layers, types of adsorbents, de­velopment of chromatograms, the vari­ous detection methods, quantitative analysis, and preparative chromatog­raphy on thin layers. Although the importance of Kirchner's early contri­butions is obvious to any careful reader of his papers, in the perspective of history, one must not completely over­look the contribution of Stahl, who in 1958 introduced TLC in its present form by emphasizing the use of stan­dardized adsorbents and equipment.

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