VOL.8.No. 7
RECEN T BOOKS
strnctor in Education, University of Southern California, and WALKER BROWN, Vice Principal of Bancroft Junior High School, Los Angeles, and Lecturer in Education, University College, University of Southern California. Henry Holt and Company, New York City, 1930. xiv X 249 pp. 12.5 X 18.5 cm. $1.36.
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publication is that it has focused its attention upon schoolroom practice. I t is t o be regretted, however, that the authors have almost wholly ignored the journal publications upon this subject. It is also disappointing to teachers of science to find but eleven pages of suggestions for the enrichment of their teaching, while there are aver thirty pages upon the enrichment of English and twenty-five or more given to the social sciences. Nevertheless the book under review is a desirable addition to the growing literature of this field of education. Especially so because of its contribution to the heretofore but scantily reported experiments of teachers who have been pioneering in this type of Nlriculum enrichment. Forward-looking teachers of chemistry who are in sympathy with the National Research Council's efforts to locate and nurture the superior chemistry student toward creative fields will find stimulation and aid in this volume. B. CLIFTORDHEmRIcKs
The book under review is "intended as a manual of practical suggestions for teachers, supervisors, administrators, and others who are faced with the problem of making the work of the school interesting and profitable for the bright pupil." There is no wish t o "deny the importance of the less-gifted pupils" but it is emphasized that the time has come for a mare "definite recognition of the interests of the bright student." Frank admission is made that the aids suggested are "drawn largely from teachers in junior and senior high schools" and so are valuable as sources of enrichment for the educational experiences of bright pupils in their secondary years. Starting with an apologeticfor a philosophy which recognizes the superior pupil in a democracy, the authors continue The Conductivity of Solutions. CECILW. with an enumeration of the various charDAVIES,M.Sc. (Wales). A. T. C. Senior acteristics of the bright pupil. After a Lecturer in Physical Chemistry. Battersurvey of various means used to identify sea Polytechnic Institute. John Wiley the bright pupil, a chapter is introduced and Sons, Inc., New York City, 1931. that considers the general problem of viii 204 pp. 22 figs. 14 X 22 cm. grouping in relation to the successful $4.00. teaching of these pupils. The extent to which curricula should be altered in minisThose interested in the conductivity of tering to the educational needs of these solutions have been pleased that in the students is then considered. These gen- last years several excellent books and eral considerations are summarized in a "Handbuch" articles have appeared on chapter which bas a sub-caption "Funda- the subject. This hook will in many mental Principles of Teaching Rapid- ways be found to be the most generally Group Pupils." The last two chapters useful of them. For purposes of review in the book contain specific applications it may be divided into two sectionsone of these principles, first, t o curriculum in which the experimental methods and and, second, to extracurriculum ma- results are briefly given, and the other terials. in which there are considered some special The reviewer has found in this one questions which can he investigated by volume an epitome of the philosoohy conductivity studies. . . and experience of those working and writing The results of experimental work are in this field. An added attraction of the discussed with particular reference to the
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JOURNAL OF CHEMICAL EDUCATION
interionic attraction throry of Dehye. Hiickel, Onsager, and others. The author points out that the conductivity of a solution will in general he determined by the relative number of ions and their mobilities, so that if the mobility changes can be accounted for, a change in the relative numben of the ions, that is, a degree of dissociation, may be calculated. The interionic attraction theory makes this p o s ~ sible because according t o i t conductivity changes are attributed entirely to the effrct of interionic forces on the mobilities of the ions. There are also chapt-rs in which relationships between conductivity and viscosity, methods of determining the equivalent conductivity a t infinite dilution, and temperature effects are considered. Among the problems considered which may be investigated by conductance studies there may be mentioned chemical analysis, dissociation of ternary electralytvs, nature of acids and bases, solvolysis, complex ions, and amphoteric electrolytes. The sections form well-written introductions t o these important subjects. The reviewer is disappointed that Dr. Davies feels "the chemist will judge the Debye-Hiickel-Onsager equations not by the manner of their derivation but by the degree of success with which they interpret and predict the results of experiment," and has written his book accordingly. Thus, less than ten pages of a third and introductory section are devoted t o a description of the theoretical aspects of the interionic attraction theories and, although the hook deals with the conductivity of solutions, only three of these pages may be said t o descrihe the new conductivity theory itself. I n this space it is possible to mention only the very simplest notions and to give the final equations, so that a reader does not have clearly before him the assumptions and approrimations which have to be made in order to calculate the "period of relaxation" effect (mare commonly called the electrical force of relaxation) and the "electrophoretic" effect. The degree t o
JULY.
1931
which a theory may be expected to fit experimental fact will depend upon these assumptions and approximations. Again, the author has all too briefly discussed the important theoretical significance of the effect of the application of high field strengths and high frequencies in the measurement of the conductivities. T t u s while the stated purpose of the book has been fulfilled to a remarkable extent, the interest of a research worker might have been stimulated to a greater degree by stricter attention to the theoretical details. This criticism should not be taken as an adverse judgment of the book, for it is primarily concerned with an account of experimental work. I t will certainly he welcomed by many persons as a clear, concise, and, a t the same time, romprehensive account of the conductivity of solotions.
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WII,LIAMS
Tne U N I V E R OF ~ ~WISCONSIN V MADISON,W~YISCONS~N
The Vitamins. H. C. SHEXMAN,Mitchill Professor of Chemistry, Columbia University, and S. L. Snnrm. Senior Chemist. Office of Experiment Stations, United States Department of Agriculture. Second edition. American Chemical Society Monograph Series. The Chemical Catalog Company, New 562 pp. 14 York City, 1931. xii figs. 16 X 20 em. 56.00.
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In the preface the authors state that "an attempt has been made to summarize the very considerable amount of information which has been gained regarding the chemical natures of the individual vitamins, and the more voluminous knowledge regarding their rdles in life processes, their formation and distribution in nature, their relative abundance in different types of food materials and stability under the conditions t o which these are likely t o he subjected." "Recognizing that knowledge of vitamins touches closely the intellectual and professional interests of many other scientifically trained persons as well as professional chemists.
