the data obtained in the course of his laboratory experimentation. In some cases, a series of questions is given and the student is expected, as a result of his experimental work, to he able to enter the answers. When questions are given, the answers required are such as to demand thoughtful deliberation on the part of the student Rarely is there a chance to guess, and the general style of the write-up is one which shows a careful attempt to reduce greatly the amount of writing required of the student so that he will have more time to experiment and to think. The manual is in no sense an attemot to relieve the student of work. On the ~ ~~~ ~~~ ~~~ ~

other hand, it i< very drfinitcly a rnanual whirh attempts ro in- crcaw fhc nrtual amount ol carcful delihcrnrivc work which can be demanded of the student.

Following the experimental work of each unit is a short list of questions and problems which relate to the experimental work, the problems, and the exercises. These are intended to assist the student in applying to new situations the general principles which have been brought out in the course of the experimental work.

The second edition of this manual is a distinct improvement over the first edition and the authors have made a real contribu- tion to laboratory teaching. Two methods of using the manual are described in the preface. If the first method is used, a carbon copy of the data and answers to questions is handed to the in- structor a t the end of the laboratory period. This method is not as favorably recommended by the authors as is the second. In using the second method, the student enters all data from each experiment and answers to questions in the proper place on the record sheets, but makes no carbon copy. Instead, the dupli- cate sheets are removed and at the end of the laboratory period and with no data a t hand, students are required to answer all questions according to their understanding of the results oh- tained from the experimental work.

Undoubtedly, many teachers will find in thismanual something which they have long sought, the means hy which a good strong laboratory course may be systematically carried out with an ac- tual reduction in the labor required of the teacher.

This manual is to be highly recommended. Every college teacher of general chemistry should have a copy.

J. 0. FRANK Srms T ~ h c n a ~ s ' C o ~ ~ a o e

OSAECOSB, WISCONSIN

ANNUAL REVIEW OF BIOCBEBIISTRY, VOLUME 111. James Murray Luck. Stanford University, Editor. Edition of 1934. Stanford University Press, Stanford University, California, 1934. viii + 558 pp. 22 X 15 cm. $5.00.

This is the third volume of a series of Annual Reviews of Bio- chemistry edited under the auspices of an advisory committee-- J. M. Luck. C. L. Alsberg, D. R. Hoagland. and C. L. A. Schmidt. I t would be impossible to cover all the literature dealing with the subject matter of the growing field of biochemistry in a book of its size; consequently, the contributors have necessarily been limited to the citation of only the most important contributions in their respective fields of work. The various topics reviewed in this volume and the respective authors are as follows: (1) Water in Its Biochemical Relation, by R. A. Gortner; Biological Oxidations and Reductions, by A. Bertho; Enzymes, by E. Waldschmidt-Leitz; The Chemistry of the Acyclic Constituents of Natural Fats and Oils, by R. J. Anderson; The Chemistry of the Lipins, I, by Smedley-MacLean; The Chemistry of the Sterols, Bile Acids, and Other Cyclic Constituents of Natural Fats and Oils, by 0. Rosenheim and H. King; The Chemistry of the Amino Acids and the Proteins, by W. Pauli; The Chemistry and Metabolism of the Compounds of Phosphorus, by H. D. Kay; Carbohydrate Metabolism, by C. F. Cori and G. T. Cori; Fat Metabolism, by W. R. Bloor; The Metabolism of Proteins and Amino Acids, by Y. Kotake; Mineral Metaholism-Sodium, Potassium, and Chlorine, by A. T. Shohl; The Hormones, by

D. L. Thomran and J. B. Collip; Vitamins, by L. J. Harris; Nu- trition, by S. Brady; Liver and Bile, by J. L. Bollman and F. C. Mann; The Metabolism of Brain and Nerve, by E. G. Holmes; The Biochemistry of Malignant Tissue, by E. Boyland; The Structural Chemistry of the Animal Pigments, by H. Fiscber and H. Orth; Animal Pigments, by A. E. Mirsky and M. L. Anson; Biochemical and Nutritional Studiesin the Field of Dentistry, by M. Koehne and R. W. Bunting; The Terpenes, Saponines, and Closely Related Compounds, by L. Ruzicka; The Biochemistry of the Nitrorenous Constituents of the Green Plants. bv H. B. . . Yickrry; hltnrralSutritiunof Plnnrs, by 11. T.undrgardh; hfelalw lisnt of Carlwhydrates and Or~anic Acids in Planti (b:rrlu.ive of Harteria and itmgi). hy W. Kuhland and J. Woli, The Chcm- istry of Bacteria, by M. Stephenson.

All chemists and biochemists are deeply obligated to the ser- vices of these contributors for the completeness and clearness of their respective reviews. The hook reflects a generous spirit of co6pperation. and will be welcomed by every progressive teacher and researcher in chemistrv. From an educational mint of view. the book is of the greatest valuc for graduate students and ad- vanced workers in hiochcmisrry. One of the hesr fcntures of the book is the extensive collection of literature citations.

THE NATURAL ORGANIC TANNINS. M. NNierenstein, D.Sc.. Uni- versity of Bristol. First edition. J. & A. Churchill. Ltd.. Lon- don, 1934. xxiii + 319 pp. 14 X 22 cm. 21s.

This hook provides a very interesting review of the various in- vestigations in the field of those rather vaguely defined materials known as tannins. The author has done a great deal of work on the subject, and does not always agree with theconclusions drawn by other notable workers in this field. The tannins are described as materials which are generally amorphous and astringent, and are widely distributed throughout the vegetable kingdom. The author divides the tannins into three groups: condensed, hy- drolyzed, and unclassified. In testing for the presence of tannin, the author prefers the gold-beaters' skin method to the other commonly known methods which use as reagents iron salts, gela- tin, alkaloids, and bichromate. A considerable amount of space is devoted to Freudenberg'r work on condensed tannins and the relation of the author's own findings to this work. Considerable space is also given to the Catechn-tannins and other condensed tannins.

The author divides the group of hydrolyzable tannins into the following snb-groups: gallotannin; acer-tannin, glucogallin, and hamameli tannin; ellagitannins; caffetannins and paullinia tan- nin. An historical review is given of the work on gallotannin. Fischer's work on this material is criticized and the author pre- sents a very large amount of his awn work in support of his criti- cism. In this group the ellagitannins are also treated in detail. In the unclassified group, the oak and sumac tannins are consid- ered as the most important.

The book contains a very interesting chapter written by Mc- Gregor Skene on the botany of the tannins. He deals not only with the distribution of the tannins throughout the vegetable kingdom but also with the parts of the cells in which the tannins are found, and the part they play in metabolism, in photosyn- thesis, and in protection against parasites.

The book contains a rather complete bibliography that should prove very helpful to all students in the field of the tannins, and also a great many interesting footnotes. Even though a reader may not agree fully with all of the conclusions drawn, he will find the book very valuable and stimulating.

JOHN ARTHUR WILSON JOnN Aarnoa WIL~ON, IN^.

CONSULTINY TANNBXS AND C A = ~ S T S MILWAUB=B, WISEONSII