BOOK REVIEWS.
[J. F. I.
practical. Each has a discussion of sufficient length to cover principles and for orientation. The last part is an appendix containing helpful tables and curves.
The subject is well presented in logical order. The plainness of the explanations and the completeness of coverage, together with the features of being selfcontained and comparatively short (some I67 pages), should make this a text and laboratory manual much in demand by engineers as well as instructors.
R. H. OPPERMANN.
MANUFACTURE OF SODA, by Te-Pang Hou, Ph.D. With special reference to the Ammonia Process, a practical treatise, the second edition. 590 pages, illustrations and tables, 16 >( 24 cms. New York, Reinhold Publishing Corporation, I942. Price $9.50. This is a subject to which there is attached increasing importance. The industryforms one of the most important pillars of the national industrial structure. This can be more easily realized when it is known that soda ash ranks next to sulfuric acid. The acid and the alkali are the two most important basic chemicals a nation possesses, for directly or indirectly, they are used as the raw materials for many other industries.
This second edition of this book has become necessary due to the rapid advances since the first edition. It is similar in construction but contains revisions in almost every chapter. There are five new chapters. The introduction is a historical survey of alkali industry and the relation of Le Blanc soda industry to the development of other chemical industries. Then there follows a discussion on natural soda. A history of the ammonia soda process precedes treatments on preparation and purification of brine, burning of limestone, ammoniation of saturated brine, working of carbonating towers, and the decomposition of sodium bicarbonate by calcination. The recovery of ammonia, the successful accomplishment of which made it possible for the ammonia soda process to compete with the Le Blanc process, is next taken up giving attention 1~o the efficiency of operation in the ammonia still, also by-products and allied products of the industry. Other manufactures associated with the industry mentioned include refined sodium bicarbonate, caustic soda, electrolytic caustic, chlorine and chlorine products. The latter third of the book is devoted to plants involved such as generation of power for ammonia soda plants, control of the process, new developments in the process, behavior of soda ash in storage, layout of the plant, and centrifugal pumps applied to the industry.
The book contains a wealth of material obtained from expert theoretical and practical knowledge of the subject and from published sources. There are many illustrations, tables and curves throughout and a comprehensive subject index in the back. It is a suitable edition to the American Chemical Society Series of Scientific and Technologic Monographs.
R. H. OPPERMANN.