VOL. 9. No. 3 RECENT BOOKS 603

term on page 113, for example. Page 56; the constants of equations 28 and 29 are different, contrary to the statement a t the bottom of the page. Page 37; the derivation of van der Waal's equation of state should be clarified. Attention should be called to the fact that the constants a and 6 are dependent on tem- perature. Page 85, Problem 2; i t would be simpler to refer to this crystal as simple cubic. Page 96; the very simple deriva- tions of the equations for specific rotatory power are entirely obscured. Page 123, line four from the bottom; the word "absorbed" should he replaced by the word "converted." Page 134; in the reviewer's opinion the Principle of Le Chatelier deserves far more emphasis than is here accorded it. Page 249; the ea- ample given is too involved to have peda- gogical value. Page 252, line four; there is an unfortunate use of the term "differential heat of solution." Page 568; Moseley used a crystal of potassium ferro- cyanide. A crystal of sodium chloride was used merely for calibration. Page 601, middle of page; the phrase "of solid elements" should follow the word "crys- tal."

In the opinion of the reviewer Dr Daniels has accomplished in a brilliant manner what he set out to do, and this edition of this popular textbook is now without a rival It merits a cordial re- ceotion.

F. L. SHINN umvens1rv ox' oaeooll

EVDHNB, OBBOON

The discussion of fundamental princi- ples is confined to the first forty pages; this includes also a brief historical treat- ment. A description of the preparation of several inorganic and same organic compounds by the electrolysis of solu- tions is given about forty pages. The electrometallurgy from solutions of cop- per, nickel, zinc, chromium, lead, tin, iron, cadmium. cobalt, silver, gold, and alloys is covered in the next one hundred ten pages. The whole field of alkali. chlorine, hypochlorite, and chlorate is confined to twenty-five pages. A few pages are given to each of the topics, "the production of hydrogen and oxygen," "the electrochemistry of gases," and "the chemical production of electricity." One chapter is devoted to the production from fused electrolytes of aluminum, mag- nesium, sodium, calcium, cerium, and beryllium. The last thirty-six pages are

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given over to furnaces and electrothermal processes. The reviewer approves this very limited treatment of electric furnaces; the only excuse for ineluding this topic a t all in a book on electrochemistry is that electrical energy rather than some other form is converted into heat, and from this point of view every housewife who uses an electric stove should be considered an electrochemist.

The index is very complete, with many cross references.

The author states, "It is the aim of this book to point out the mdre important applications of the electric current in the manifold phases of chemical manu-

Electrochemistry. Prmciples and Prac- facture, . , has been made the. C. J. BROCKMAN, Associate Pro- to present eledroehemistry in not too fessor of Chemistr).. University of technical a manner so that it will interest

Georgia. D. Van Inc., the chemist, the plant manager, the New York City, xi + 348 pp. manufacturer, and the fringe of business 47 Figs. 14.5 X 22 cm. 84.00. men who are not necessarily adepts vith

The title of the book given on the cover electrochemical manipulations; yet it is is likely to be misleading. From the hoped that the scientific value of the title and the size of the hook one gets work will not be lost to the virtuosi of the idea i t is a treatment of fundamental electrochemistry." If considered from principles only. The title on the title the point of view of these objectives. page, "Electrochemistry. Principles and the book is well done. A sufficient Practice," is more enlightening. amount of the historical, theoretical, and

604 JOURNAL OF CHEMICAL EDUCATION M m , 1932

practical sides of the subject is given to arouse the curiosity and maintain the interest of the type of reader for whom the author states the book is primarily written. Such a reader would not ap- preciate the fine points of electrochemical theory or complex mathematical deriva- tions, or the details of plant operation; and if they had been included the reader would probably lay the hook aside before he progressed far, with the feeling that i t is beyond him. The specialist in the field can supplement the material in the text through recourse to the many refer- ences to current literature.

There are several errors, some unfortu- nate choices of illustrations, and a few omissions. The most important of these that the reviewer observed are given below. The expression, "specific conductivity"

is frequently used in place of "specific conductance" or "conductivity."

The incorrect idea, presented in a large majority of the textbooks on physics and chemistry, that sodium ions and anions such as SO,-- in a water solution, may be discharged a t the electrodes and the resulting products then react with the water, still persists in this hook.

In the development of the idea of de- composition potentials on pages 18, 19, and 20, in addition to the selection of unfortunate examples, the author has shown faulty reasoning and a misuse of terms. The whole discussion is highly confused. The confusion persists also on page 22, where the figure and discussion given for "case 11" applies really to "case 111."

On page 24 the reader might get the notion that a hydrogen electrode "con- sists of a plstinum-black electrode of definite dimensions"; hut, of course, no "definite dimensions" are required.

The reviewer questions the advisability of the use of such expressions as "the CuC concentration in these solutions is as low as 10-' normal."

The statement that "there has not been very much scientific study of brass depo-

sition" might be questioned. The author does not include references to many of the more recent investigations on the eledrodeposition of brass and other allays.

Considering the readers for whom the book was written especially and the ex- tensive use of the lead storage battery, a fuller discussion of it might well have been included. In the discussion of the lead cell the statement is made, "The discharging voltage is higher than the voltage of discharge as shown in the ac- companying curve." This statement is confusing, especially as there is no "ac- companying curve."

In discussing the Edison cell, the state- ment is made, "it consists of a positive electrode of h e l y powdered iron . . . During the course of discharge the nega- tive electrode undergoes a transforma- tion to Fe(OH)*." There is confusion here in the use of "positive" and "nega- tive."

The use of inhibitors in connection with pickling baths has assumed such importance recently that the topic might well have been referred to in connection with cleaners.

The presence of many of the errors noted above, and others not mentioned, are probably due to the proof not having been carefully read.

A. L. FEncusoN

Chemical Arithmetic. SAUL B. ARENSON, Associate Professor of Inorganic Chem- istry, University of Cincinnati. John Wiley and Sons, Inc., New York City, 1931. v + 108 pp. 14 x 21.5 cm. $1.25.

The solution of a chemical problem would be materially simplified if the student would read the problem, analyze it and plan a mode of attack. After calculations show the student the answer, he should be able to say "that's just about what I thought the answer ought to be." In line with this, answers are given in a fitting manner: "code" answers