manuals-such as the preparation of gaseous hydrogen and oxygen-be dropped from instruction, to make room for general concepts of growing importance, such as acid-base and ouidationreduction equilibrium?
(TextL ~ m u c DER n CHEMIEFUR H ~ H E R ELEHRANSTALTEN. book of Chemistry for Secondary Schools.) Part 1. Rudolf Winderlich, Head of the Board (Oherstudienrat) a t the Oberrealschule, Oldenburg in Oldenburg. Fifth revised edition. 143 pp. 15 F. Vieweg und Sobn. Braunschweig, 1936. vi X 22 cm. 80 figs. 2.88 R.M., hound.
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This is the 6fth edition of a book that has been used since 1921. In order t o provide pleasant and instructive reading for young students. Professor Winderlich has omitted some material that appears in most textbooks of chemistry and has introduced brief and appropriate citations from the scientific classics. The familiar metals and solid nan-metals are introduced before the gases. Chemical formulas and equations are used only in the last twothirds of the book. Roman, italic, and hold-face type and the customary double-spacing far emphasis dearly differentiate the desriptive and experimental portions without the use of any unpleasantly small type. Most of the experiments are marked SV (Schiilerversuch), but a few of the more difficult anes are marked LV (Lehrerversuch). I n connection with the experiment on the ignition of limestone, the students learn that, centuries ago, the Roman architect Vitruvius mentioned the loss of weight which they have just ohserved. They then repeat several of Joseph Black's famous experiments which led to a correct and complete explanation of this reaction. The discussion of combustion is interspersed with citations from the original papers of Scheele and Lavoisier. The atomic theory is introduced by an appropriate quotation from Lucretius' famous poem, "On the Nature of Things," translated into German verse by Goethe's friend, K. L. von Knehel. The book contains valuable information about German chemical industries. The first boring for salt was made in 1812 a t Jagstfeld near Wimpfen on the Neckar after a sinking of the earth's crust a t MBckmiihl had unexpectedly exposed the rock salt. The boring a t Stassfurt was begun in 1839, and the salt was not reached until four years later. These great deposits of potassium salts have heen productive since 1857. Professor Winderlich emphasizes the practical aspects of chemistry, and, in this book for beginners, makes no mention of the dissociation theory. The seven-page supplement on protection fram fire and poisonous gases contains fire-extinguishing experiments which might well he included in every course in general rhemistrv.
I n the chapter on sulfur there is a clear description of the remarkable F r m h process of melting sulfur underground and pumping it t o the surface, which gave the otherwise inaccessible deposits of Louisiana their supremacy over the ancient Sicilian ones. After the student observes the deposition of sulfur caused by the action of sulfur dioxide on hydrogen sulfide, he reads Bunsen's description of the hot springs of Iceland, in which Nature performs the same experiment on a grand scale. The harmful e5ect of sulfur dioxide in the atmosphere is illustrated by the carrosiou and breaking of copper telephone wires in Berlin and t h e damage t o the Cologne Cathedral. Dr. Winderlich shows how world supremacy in copper production has shifted throughout the centuries from one country t o another. I n ancient times Egypt, Carthage, Numidia, and Cyprus were the great producers; in the fifteenth and sixteenth centuries Tyrol and Hungary ruled the market; during the seventeenth. the =eat Fahlun Mine in Sweden held swav. I n more recent times Russia, Cornwall, and Spain have successively played the leading r&, and a t present the United States produces more than half of the world's output of copper. The dissociation theory is briefly discussed, and some of t h e equations in the latter half of the book are written in the ionic form. The last eighty pages are devoted to organic chemistry. T h e importance of combustion methods of analysis is emphasized b y a quotation fram Liebig: "For the analysis of seven organic acids. the former [Berzelius] required eighteen months, and M. Chevreul worked thirteen years on the analysis of the fatty substances he discovered. With the aid of our present method, Herr Berzelius would have required only four weeks a t the most and M. Chevreul perhaps two years instead of thirteen." The following statement is quoted as Lavoisier's &st chemical equation: "Grape must = carbonic acid alcohol." The chemistry of ethyl alcohol and the technology of brewing and distillation are discussed in detail. The author states that Germany is suffering from overproduction of alcohol, much of which is unfortunately consumed in the farm of beverages. He observes that neither high taxation in Germany nor prohibition in: the United States has succeeded in controlling this evil. American students who are learning to read scientific German will enjoy Professor Winderlich's pleasant literary style and clear expositions and will be interested t o learn how modern German chemists are meeting their difficult economic problems. MARYELVIRA WEEKS
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U ~ l v a a s r rOF ~ K*N.*S LAITRBNCB. KANJI.
DIFFERENTIALEQUATIONSIN APPLIED CHEMISTRY. Fmnk Lauren Hitchcock, Ph.D., Professor of Mathematics, and Chrk Show Robinson, S.M., Associate Professor of Chemical Engineering, Massachusetts Institute of Technology. Second edition. John Wley & Sons, Inc.. New York City, 1936. viii 120 pp. 12.5 X 18.5 cm. $1.50. Any chemist who has had a course in the fundamentals of calculus can easily comprehend and profit greatly from a stgdy of this practical little book. The illustrative examples a r e dearly explained and the exercises cover subjects ranging from chemical kinetics and flow of liquids t o growth of population and interest rates. Emphasis has been placed, not only upon t h e expression of the problem in the form of a differential equation, hut also upon the various ways in which the numerical calculations can he accomplished. The second edition has many new problems and the old ones have been revised along with the insertion of data from recent literature. The discussion of Fourier series has been amplified and a chapter has been added in which the numerical solutions of differential equations of types difficult to integrate are discussed. Every student of chemical engineering should own a copy of this hwk. Many of the problems and methods could well h e incorporated into the standard year's course in physical chemistry. E D W A BL.~ HAEMSCH
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Part 2. L ~ x n a u mDER CHER ~ H6HERE R LEHRANSTALTEN. Advanced Course.. Rudolf Winderlick Third revised edition. F. Vieweg und Sohn, Braunschweig, 1932. viii 297 pp. 15 X 22 crn. 198 figs. 6.40 R.M.
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This is the third edition of a hook which 6rst appeared in 1924. Since i t is intended far students who have completed the elementary course presented in Part 1, it contains many quantitative experiments, detailed descriptions of many industrial processes, and valuable information on the economic aspects of chemistry, especially in Germany. The chapter on the noble gases has an interesting historical introduction. At the hegioning of the nineteenth century the Munich Academy of Sciences offered a prize for the solution of the problem as t o whether or not nitrogen liberated from its compounds is identical with that of the atmosphere. This was not salved, however, until nearly a century later, when Lord Rayleigh's masterful determinations of the density of nitrogen led to the discovery of argon.
V&G*NOYA COLLBOB V,cLbNOV*.
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