(Chapter VII), absorption of light by matter in the adsorbed state (Chapter VIII), the selective photoelectric effect (Chapter IX), photoelectric properties of alkali halides (Chapter X), and photoelectric cathodes of composite type, such as Ag-C%O-Cs (Chapter XIII). IV. Electronic conduction in lattices of alkali halides and similar compounds (Chapters X I and XII), and conduction in blacking layers (Chapter XV). I n t h e first chapter the author gives a list of references to recent reviews on the subjects of thermionic emission, the photoelectric effect, and the most recent developments in the theory of electronic conduction. Therefore, instead of duplicating, in a sense, the contents of these publications, he has described only the main features of the phenomena and has dealt a t greater length with the bearing of these observations on the interpretstion of the nature of adsorption forces. The discussion of each topic is accompanied by very clear diagrams which should prove of material assistance to the reader. No difficult mathematics is used in presenting the interpretation of the various types of observations. Chapters X I and X I 1 (dealing with electronic conduction in the lattices of alkali halides and similar compounds) contain a very fine review of a group of phenomena which will no doubt become of more universal interest in the future from both the theoretical and practical points of view. Perhaps the author has dealt more fully with his own views on some of the phenomena than with'those of others. But he has also attempted to present opposing points of view, as, for instance, in the chapter on the adsorption of caesium on tungsten surfaces. Since each chapter contains copious references to the literature, the reader is enabled to follow up each topic in further detail, should he desire to do so. For the chemist, the study of the contents of the volume will prove stimulating since they deal with that borderland in which the physicist and the chemist must ob\perate t o understdnd the nature of the phenomena observed. I t is a field in which the physical chemist or chemical physicist will continue to find many interesting problems for a long period of time. The reviewer feels that the work of Dr. de Boer will prove both nrofitable and stimulatine to all those who desire to keen abreast of thr dcvclopn~mtswhich have resulted from thr inwstigations in thcrmiunirc. photorlcctric, photoconduc~ion,and electronic conduction phenomena. SAULDUSHMAN
and to considerable advantage, with the use of aromatic compounds." This may be admitted in principle, but in view of the recent and contemporary growth of aliphatic chemistry the advisability of including only thirteen aliphatic experiments in a total list of over fifty may be questioned. Part I is introduced by experiments on the detection of the elements and on the manipulations of distillation, fractional distillation, determination of the melting-point, cryetalliwtion, and extraction. The experiments which follow are mostly preparations, for which the procedures appear to be excellent, and are carefully and clearly described. Among the experiments which present an aspect of novelty there may be mentioned the use of "dry ice" in the synthesis of a carboxylic acid through the Grignard reagent, the removal of water from a product (valeric acid) by azeotropic distillation, the reduction of acetone to pinacol and its conversion to pinacolone, the acetylation of an amine (aniline) by aceticanhydrideinaqueous solution, the preparation of benzophenone by decarboxylation of o-benzoylbenzoic acid, the photachemical reduction of benzophenone to benzopinacol by isopropyl alcohol, the auto-oxidation of benzoin, the Perrier modification of the Friedel-Crafts reaction, some good experiments on dyeing, a brief outline for identification of certain types of aromatic compounds, and a special experiment on Martius yellow. The last is a small-scale experiment involving eight steps, and is suggested as a test of skill and speed. The text of this experiment comprises four pages explaining the somewhat formidable chemistry involved, about two pages of general instructions, five pages of directions, and over a page of "notes." Considered individually nearly all the exercises in the manual are to be recommended. Considered as a course of instruction, however, the manual discloses a certain lack of balance and scope. I n addition to the great preponderance of aromatic experiments, attention may be called to the facts that there are described the preparations of two pinacols and the corresponding pinacolones, the (alternative) preparation of two acids by the Grignard reaction, three sulfonations, two preparations of phenols by alkali fusion, four quinones, and no fewer than six FriedelCrafts reactions. These duplications serve to emphasize a number of omissions of familiar and useful material, of which a t least a part is generally considered essential to a n elementary course. These omissions include a study of thecharacteristics of alcohols, the preparation of alkyl iodides i h d chlorides (not mentioned), the preparation of a simple aryl halide, the properties of aryl halides, the Ullmann reaction, the Cannizaro reaction, work on co. pentoses and furfural, study of aliphatic amines, examples of alkylation (other than by the Grignard reagent), study of intermediate reduction products of nitro-compounds, reactions of Louis F. Fieser, AssociEXPERIMENTS IN ORO~WIC CAEMISTRY. amines and amides with nitrous acid, saiyation of a double bond, a t e Professor of Chemistry, Harvard University. D. C. Heath introduction of multiple bond by ahstracfion of hydrogen halide. and Co., Boston, Mass., 1935. viii f369 pp. 42 figs. 13.5 X The Wurtz-Fittig synthesis, and theacetoacetic ester andmalonic 21.5 cm. $2.40. ester syntheses, are omitted. There are no experiments in either the alicyclic or the heterocyclic series (unless succinic anhydride, This new laboratory manual is intended for students of ele. mentary organic chemistry, and especially for those who expect succinanil, and phthalic anhydride are t o be regarded as true heterocycles). t o undertake more advanced work later. I t is divided into two Discussions of steam distillation and vacuum distillation are parts, of which Part I (pp. 1-280) presents 6fty experiments, some comprising several parts or alternatives, and Part I1 (pp. introduced a t appropriate places, and are excellent and relatively 281-359) consists of chapters on suggestions for advanced work, full, with figures representing various useful types of apparatus. solvents, reagents and gases, and a semimicro method for the The determination of melting points is perhaps less satisfactorily treated than other important operations. The student apparatus determination of carbon and hydrogen. The manual differs from many of its predecessors in a t least recommended, and also the modified Anthes apparatus shown in two respects. (1) Each experiment or each procedure is pre- Part 11, appear to provide insufficient certainty of uniform heat ceded by a n informative introduction in which the student is told transference, and no satisfactory means for estimating the correcsome of the things he should know about the methods available tion for exposed stem. The student is informed that the error and the ones employed, for the preparation, isolation, etc., of the due t o exposed stem may reach lo", but the question of stem product to be made, and in which the essential chemistry of the correction is dismissed rather casually (p. 289) in a manner which experiment is explained. This undoubtedly facilitates matters appears to condone a practice termed by Mnlliken "unfortunate for the student. and will mohablv lead to a better averaee state - - of - and unscientific." The chapter on Identification of Organic Compounds presents prrparednrss when each rxpcrimrnr is udrrtakcn, rhuuyh it may ir~clucrrume\tudrnts rorclv o r h l y upon r l t r ~ ~ c x p l a n a t ~ o n s a s a na brief scheme which provides for the actual or proximate identification of "a rather small group" of aromatic types (exclusive of hydrocarbons, halides, and phenolic ethers). The primary classification is essentially that of Kamm; the functional tests reactions of aliphatic chemistry can b i illustrated perfectly well, applied are those previously performed as parts of earlier experi-
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twenty-two of the hooks cited are among the number recommended by a recent committee of the American Chemical Society, but the reviewer confidently endorses the author's list. The second teaching device, usually called a summary, here takes the form of a statement of "basic principles." These are worded less formally and more interestingly than the usual textbook summaries. We wish some one would determine just how this feature of the average book is best used. The third device is the usual list of questions and problems with the former greatly predominating. The question is the best thought-provoking device of the teacher, provided the pupil has a sufficient introduction to the field in which the question is placed. There are, on the average, thirty-six questions to each chapter, or two pages out of each fifteen of tent. This far exceeds the proportion found in other texts. This book is the second one t o provide advanced exercises for the ambitious or proficient pupil, the last five or six exercises of each group being so indicated. The claim is made that the questions are graded, but there is much more grading needed. The exercises recommended for the average pupil include purely mechanical questions to cause a re-searching of the text, as well as some others which call for the application of text material to life laboratory instruction, and equally useful as a source of informa- incidents. The latter are the really educational questions. tion and of supplementary or alternative experiments for students Finally, there are questions for which no preparation has been generally. E. C. WAGNER consistently made and which throw the pupil upon his own resources. These should be placed in the advanced group as being U N I Y G R S I N OX.PENNSYLVANIA suitable for only the most capable pupils. PmLADELPHI*, P*. Neu World of Chemirtry is the fifth new text appearing during NEWWORLDOF CHEMISTRY.Bernard Jaffe. Chairman, Depart- the last year and a half as the product of one author. It compares ment of Physical Sciences, Bushwick High School, New York very favorably with the others in having no conspicuous errors of fact. There are, however, points of view which are open to City. Silver Burdett and Co., New York City, 1935. xii 566 pp. Appendix and index xxx pp. 339 figs., unnumbered. challenge. The discussion of "water of crystallization." together with its implied definition of the term "anhydrous," might be 14 X. -~ 20 cm. $1.80. - , . ~ - ~ cited in instance. This book greets the reader with an attractive title and modern- . Chapter 6 explains the origin and use of formulas excellentlv istic cover, suggestive of chemical magic in story form rather than and chapter 8 has an adequate treatment of equations. what a textbook which may be dull t o the young mind. The author can justify the general use of both in chapters 2, 3, 4, and 5? franklv admits that his work is concerned with onvevins ~, to the Of course, pupils will survive this treatment, but is i t the sciengrrat mass of thr population the it~flt~mcv : j n d ideels of scientific tific method? Any real student will want to know why the factor ir.quiry and thc scientific method rathrr than with msking a fcw and subscript for oxygen are interchanged when 30r and 2Fe10r scare narrow specialists. However, it is not inconceivable that are written in the same equation. I n such a case the teacher's both cultural and professional education may be based upon the position is indefensible. . same type of introduction, and this text furnishes a better guide Chapter 1 gives an adequate statement of the six essential book for the purpose than any with which the reviewer ac- steps of the scientific method. Exercise 17 a t the end of the quainted. There is a freshness of viewpoint and a practicality in chapter is. "State the six steps in the scientific method." How presenting the subject matter that brings the world of chemistry much better than the exercise is a plan t o illustrate the use of the closer to the experiences of life. The author is particularly fitted scientific method by a simple experiment, a t the same time giving by his historical studies to interpret the progress of the chemist in the pupils an opportunity to exwcise their reasoning powers in the past. His previously published "Crucibles" is appreciated making up their own minds about the nature of a-phenomenon by many. In two of theeight objectivesstatedin the preface, the from the facts. value of a knowledge of the lives and labors of eminent%cientists Few texts escape the giving of wrong implications about is emphasized. I n this connection, the author pays emphatic neutralization. "A definite quantity of heat, 13,700 calories, is tribute to the specialists rather than the masses. liberated per gram molecular weight (mole) of water or of the salt The book is divided into 38 uniform chapters averaging 15 formed . . . . In the case of the action of sulfuric acid on potaspages each. The titles constitute more than a subject classifica- sium hydroxide, 2 X 13,700calories are formed, due to the formation; descriptive phrases are added. This is a step in the right tion of two moles of water." But there is only one mole of the direction, for what the materials can do is more important than salt formed so the neutralization is not "the uliion of an acid and a what they are. Each chapter is uniformly concluded with three base to form water and a salt." teaching d e v i c e s a selection of reading materials, a summary. The abundance and choice of illustrations are practically above and a collection of questions and problems. criticism. The drawings are excellently done by a special artist The reading lists are more systematic than those in any other and the halftone illustrations are clear and distinct. The wellhigh-school text extant. Not only is the source book with arranged chapter on electrons and protons contains portraits of specific pages given, but also suggestive hints of its nature that many modern scientists a t their famous labors. The publishers will surely help to arouse the pupil's curiosity. A total of fifty- may well be commended for the quality of paper, the clear typogfive books besides periodicals, all well selected, is listed through- raphy, and the mechanical make-up in general. There are ways out the whole book. This represents a library cost of nearly that we have mentioned in which it could be improved, yet its $200. Only the largest schools could afford them all, and would appeal to the pupil, its practical attitude toward the human not purchase them a t one time. Since only Sixteen book refer- things of life, and its wealth of illustration place it in the front ences occur more than once, it is evident that the library lint rank as a superior textbook in chemistry. should be graded. Small schools might then be encouraged to feel that it was worth while to have some of the library. Only
ments. Work of this kind is always interesting to the student, and repays the time devoted to it. Part 11, which discusses certain apparatus, chemicals, and procedures used in advanced work, is for the most part brief, and is more fully documented than Part I . This section is valuable, though i t appears that certain portions might logically be given in appropriate places in Part I and thus become available to elementary students. The chapter on Solvents. Reagents, and Gases is morevaried and useful than the title suggests, hut cannot well he described or evaluated briefly. The information regarding the Grignard reaction could perhaps be advantageously included in Part I with experiment 12. The final chapter on the semi-micro determination of carbon and hydrogen describes the procedure of Lauer and Dobrovolny, which "is gaining rapidly in popularity both in advanced courses of instruction and in research laboratories . . ." The description is adequate, and indudes a number of simplified alternative manipulations. The book is well and clearlv written. Onlv a few tvooeraohi-
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