BOOK REVIEWS

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906

T H E J O U R N A L OF I S D U S T R I A L A N D ENGIiZTEERING C H E M I S T R Y

V O ~ 1. 1 , NO. 9

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BOOK REVIEWS An Introduction to the Physics and Chemistry of Colloids.

centration of boiler water within such limits that soluble salts By EMIL HATSCHEK.3rd Ed. 116 pp. 1 7 illustrations. shall not exceed 1000 grains per Imperial gallon (about 14,000 P. Blakiston’s Son & Co., Philadelphia, 1919. Price, $1.50, p. p. m.), otherwise sodium chloride and sodium sulfate will net. deposit. The second edition of this book was reviewed in THISJOURNAL, The likelihood of corrosion following the use either of “peaty” 8 (1916), 1181. In the third edition “A number of small correc- water or of that containing salts of magnesium, especially tions and additions have again been made so as to include such the chloride, is naturally touched upon; and much discussion, with illustrations, will be found bearing upon the general subrecent advances as fall within the purview of a brief introduction to this branch of science.” The usefulness of this book as an jects of corrosion, scale formation, and methods of combating introduction to the subject of colloids remains as great as be- these evils. Under “priming,” exception is well taken to the widely confore. At present, a knowledge of the fundamental facts and methods as developed here is of special importance, since the ceived notion that alkalinity fier se will cause foaming, and illustrations are given to show the fallacy of this belief. study of the colloidal properties of matter is +ending toward The many analytical tables in the last chapter cover waters explanations of a more quantitative chemical and physical from nearly all parts of the world except continental North character with a consequent simplification of the relationships America. This omission makes the book less useful to American involved. readers than it would otherwise have been; nevertheless, those K. GEORGEFALR interested in boiler waters will find in it much that is valuable and instructive. Boiler Chemistry and Feed Water Supplies. By J. H. PAUL. W. P. MASON 242 pp. Longmans, Green & London and Xew York. Price, $4.50, net. Crude Rubber and Compounding Ingredients. By HENRYC. American readers of this English book must remember that PEARSON. The India Rubber World, 1918. Price, $10.00. the very numerous analytical results which are stated in “grains This, the third edition of this book, aims to bring up to date per gallon” have to do with the British Imperial gallon and not with the United States gallon. The former is a larger unit of information regarding crude rubber and compounding inmeasure than that commonly used in this country and it con- gredients. It is not, as i t makes no pretense to be, a treatise on India rubber. It is rather a dictionary of materials used tains 70,000 grains of water. Moreover, hardness is expressed in the old form of degrees, in the art with the description of their method of preparation, a degree representing hardening material equivalent to I grain properties, and use in connection with rubber manufacture. In comparison with previous editions, more space has been given of calcium carbonate per Imperial gallon of water. in the present volume to the description of plantation rubber, The first chapter opens with analyses of sundry atmospheric waters, rain, hail, and snow, attention being called to the acid its preparation, uses, etc., and to recent developments in concharacter of such of these as fall over city areas. Fourteen nection with the same; in this edition also will be found speciaI chapters devoted to such subjects as accelerators, synthetic diagrams follow, giving in graphic form the amounts of fixed and free carbonic acid found in London water; and the chapter rubber, the reclamation of rubber, and the vulcanization of closes with many detailed mineral analyses of soft waters, rubber without sulfur. Perhaps the most striking fact to be learned from a review chalk waters, magnesian waters, and waters from rivers, canals, collieries, wells, and seas. Under soft waters the author does of this book is the enormous number of materials which have been recorded in the literature in connection with the manuwell to point out that such may be found even in chalk deposits facture of India rubber. The work of bringing together under in the absence of carbonic acid. one head-and appropriate title all such materials in itself speaks Chapter 3 has to do with the more common constituents of natural waters, and tables are given showing their solubilities for the value of the present volume as an encyclopedia of rubber a t different temperatures. Those familiar with waters from the and its compounding ingredients. Not all the materials o r processes, however, described in this volume can be successfully Far West would add sodium carbonate to the list, In Chapter 4 are given detailed analyses of many varieties used; many of them are obsolete or of no practical value whatsoever. Perhaps the weakest point in connection with the of boiler scales and sludges. volume lies in the fact that little or no effort has been made to I n the chapter on softening, the author reminds the reader distinguish between materials of proven, practical value and that simply bringing water to the boiling temperature is not sufficient for the entire removal of free carbonic acid but that those of merely scientific or historical interest. Thus, for example, in the chapter dealing with accelerators, one page will actual boiling for ten minutes is required. I n the same chapter are to be found tables for use when be found devoted to quinoline and its derivatives, all more or testing lime water and soda ash, together with factors suitable less useless materials for practical purposes, while some of the best of everyday accelerators receive but scant mention, for calculating the quantities of softening materials required Similarly in the chapter devoted to resins, gums, etc., no mention to remove the various forms of hardness. The author is pronounced in his view that for boiler use all a t all is made of the millions of pounds of glue annually consumed hardness should be removed for the reason that partial softening in compounding with India rubber for tires and other purposes. may allow corrosive salts to remain even after the “scale-formers” On the whole, however, the volume should commend itself have been extracted, thus making the last state of the water to the practical man as a work to which he can refer. The worse than the first. chapters dealing with crude rubber and pseudo-rubbers and The statement (page 107) that the natural zeolites are hardly their preparation are particularly valuable and interestingI n another edition i t would seem that some mention should be sufficient in softening power to permit of their competing with the artificial is scarcely true, as several of these latter are al- made of the subject of fabrics used now so extensively in t h e ready on the market. rubber industry. Emphasis is placed upon the necessity of keeping the conD. SPENCE

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