this hell hut also provides good reading for any chemist. About one half of the book consists of well-chosen excerpts from the works of the founding fathers of organic chemistry, expertly woven by Benfey into a fascinating tale. Benfey sets the stage by a few pages on the state of the art just before Wbhler, with special note of the dualistic theory of Berzelins and its failure with organic compounds. He then discusses the Wahler-Liehig discovery of isomerism, Wdhler's synthesis of urea, and the impact of these two events on the chemical world: the vital force doctrine had received its first challenge and organic chemistry as physical science was under way. Hewing to objectivity rather than either legendbreaking or legend-making, Benfey writes, "there is no doubt that the urea synthesis provided a powerful impetus to chemists trying to find order in the field of organic chemistry.. . . The synthesis of urea did not of course immediately destroy the dichotomy between the realms of organic and inorganic chemistry. . . . However, even the discoverv of a horderline case was important, f o r . . [a] marginal region can be explored and many chemists were fascinated by the prospect." (Pp. 23-25.) The first major advance after the urea breaktbrough was the radical theory, initiated by Liehig's and WBhler's work on henzoyl. Benfey captures the essence of this rather complicated piece of detective work in a remarkably clear manner. The case of the smoking Tuileries candles then leads to Dumas and the substitution theory, squarely in opposition to the dualistic theory and setting off the furious and sometimes hitter debate that occupied organic chemistry far two or three decades. The reader is guided through the tangled controversies and oantrihutions of Laurent, Gerhardt, Dumas, Williamson, and others and gains an unusually clear picture of substitution, radical, and type theories. The work of Frankland, Kekul6, and Couper then comes as an intellectual climax to the story. Benfey's excerpts from and comments an Couper are particularly revealing of the background of genius. Editor Harold Hart, in his introduction to this hook, says that "scientific discovery is a thrilling and exciting process, and a zest for it should he imparted to the heginning student." These words are wellfitted to the hook, which should be enjoyable and worth-while reading for both teachers and students.
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lected excerpts from the original literature, tied together and explsjned by s knowledgeable writer. As a result, the student gains a picture of science as an active pursuit of bowledge, as opposed to the too-familiar picture of science as a passive body of knowledge. In this volume, J. 3. Lagowski deals with atomic theory from Thomson to Bohr. Liberal use of original passages and diagrams from the works of Thomson, Rbntgen, Becquerel, the Curies, Rutherford, Soddy, Moseley, and others provides a vivid account of the how and why of the discoveries of the electron, radioactivity, isotopes, and the nuclear atom. The final major topic is the Bohr atom, which is handled well hut without the extensive quotes and excerpts which mark the rest of the hook. Students who are not acquainted with elementary physics will perhaps not follow same of the mathematics, hut this should not interfere with their grasp of the mein trend of thought. All in all, the book is not only understandable hut also an invitation to further studv. The teacher who recommends this hook to his students should perhaps clarify one point. Lagowski implies that classical quantum theory was completely successful m d then writes that wave-particle complementarity is a philosophical problem, thst "the nature of science is such that new ideas [sic] continuously alter the results of previous theories," and Iinally that "the results of these [wave-mechanical] calculations agree in general with those of the more simple Bohr concept." The impression a beginning student is likely to get is that the Bobr theory is an entirely valid one and that physicists later arhitrarily chose to make things unnecessarily complicated. The genius of Bohr and the hddness and worth of his "atom" would he better served by a frank account of the limitations of the theory. Nevertheless, the hook should he a good adventure in thinking for freshmen. I t is not merely a history book hut rather a unique opportunity to read some of the aetud archives of science a t a level 80cessihle to the non-expert and even to the beginning student.
IRWIN COHEN Youngsfown University Youngsfown,Ohio
Identification of Materials via Physical Properties. Chemical Tests, and Micror-
kouncstown, O ~ W
The Structure of Atoms
J. J. Lagmuski, University of Texas, Austin. Classic Researches in General Chemistry. Houghton Mifflin Co., 120 pp. 15 X Boston, 1964. vii 23 cm. $1.95.
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This paperback is one of the fint under the series title, "Classic Researches in General Chemistry." The objective of the series, successfully fulfilled here, is to provide beginning students with se-
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Journal of Chemical Education
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A. A. Benedetti-Pichler, Queens College of the University of the City of New York. Acsnlemic Press, Inc., New 492 pp. Figs. and York, 1964. xi tables. 17 X 25 em. $18.
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A chemist is frequently called upon to answer the questions, "What is it?" and "What is its chemical compcmition?" Samples brought to him may vary from Imee -~ rooks to ~oeeks of imourities in an ~~~-~ otherwise pure substance. 'The &blem of properly identifying an unknown suhstance is indeed a difficult task and the chemist will find this book very helpful. The author points out that '%he hook has
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been written for the practicing chemist whose occasional task may be qualitative I t emphasizes the identifianalysis.. cation of materials-inorganic, organic, biological, common, rare. .as they actually occur in nature and industry.. ..'I The hook emphasizes techniques and methndology rather than theory. It is divided into two parts. Part I (about 200 pages) is concerned with the technique of observation and manipulation. The first section gives an excellent discussion on the use of the microscope with clear and detailed directions. Part I diieusses such various teohniques as work on the gram, centigram, milligrrtm, submilligram, and microgram scales. The section on the submilligram scale includes directions for spot tests and microscope slide tests. In all sections, specific experiments and practice exercises with detailed directions are given. This is especially valushle since the investigator is able to carry out the experiment with a known suhstance to develop his technique and to verify the accuracy of the
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Part I1 (about 250 pages) discusses systematic analysis. The following topics are covered: sampling, preliminary inspection, non-destructive testing, classification tests, and a lengthy section on eanfi~matory tests for various cations. Separation methods are then discussed followed by detailed flow diagrams for the separation and identification of the cations including the rarer elements such as beryllium, tungsten, uranium, etc. Most of these follow the classical scheme of 'qualitative sndysis using hydrogen sulfide. This is followed by a section covering a systematic procedure for the anions. Part I1 concludes with a section in which Dr. Benedetti-Pichler states, "the most important part of the analysis is the final conclusion." His suggestions should be verv, heloful. Tlrc .\ppcndir (rlwll 20 paycr) included d~rcct~ons for prepanti): mt sdutions and unknowns. (Directions for preparing various reagents are usually included with each specific procedure). Tables of crystal forms, colors, and melting points of inorganic compounds are given. The final section consists of approximately 1200 references oonveniently arranged in various categories. Most hooks in the field of qualitative analysis are highly specialized, i.e., inorganic, arganio, microscopy, instrumentd, etc. In order to identifv a substance of unknown comuosition. ihe snalvst mav find it uecess& to cdnsult seve;al references before he can find a. workable method. Dr. Benedetti-Piehler has masterfully presented d l of this in a single volume. The bookis well organized, clearly written, and reflects the author's many yeam of experience in the field. It is recommended for the libraries of all chemists concerned with quditative analysis and should serve also as a. useful textbook for a senior-level course in identification analysis.
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R l c ~ n n oB. HAHN Wayne Slate University Detroit, Michigan
(Continued a page ABO)
