The chemistry and technology of waxes

Newton and the wave theory suggested by Huygens finally ended apparently in a .... mount hut also the percentage of cdcium in their bodies to accompli...
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APRIL. 1848

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a description of the experimental con6rmation by Heinrieh Hertz, in 1887, of the "highly mathematical theory concerning light, electricity, and magnetism proposed twenty-three years before hy the Scottish ohvsicist. James Clerk Maxwell." In order to transmit the elec&o-gne'tie waves, physicists assumed the existence of a "luminiferous ether," whose only reason for existing was to function as subject far the verb "undulates!' The struggle between the dart theory proposed hy Sir Iswe Newton and the wave theory suggested by Huygens finally ended apparently in a complete victory for the adherents of the latter. In Chapter 11, which is presentea by the author as the fist scene of Act I of the drama, the story is told of the manner in which Planck was led to conceive the quantum hypothesis. Thus was introduced into ~hvsicsthe mvsterious constant "h!' Whereas Planck was somewhat apologetic in expressing his ideas, Einstein (1905) boldly went the whole way and "developed the startling idea of a definite atomicity of energy." This is the topic of Chapter 111. Is light s. wave or particle? In Chapter IV, entitled "Tweedledumand Tweedledee," there are described the results obtained by C. T. R. Wilson, A. H. Compton, and R. A. Millikan. The physicists "could hut make the best of it, and went around with woebeeone faces sadlv com~laininethat on Mondavs. Wednesdays, ind Fridays tbly must lookon light as a. waye;' an Tuesdays, Thursdays and Saturdays, as a particle. On Sundays they simply prayed." Meantime Rutherford had ~roposedhis nuclear model of the atom and Niels Bohr combined this model dong withthe quantum hypothesis and classical dynamics to formulate a theory of energy levels for atomic systems which yielded not only s n interpretation of the oriein of soectra lines but also a value for the Rydberg. constant based sd~elyon values of e, m, and h) in excellentagre& ment with the value observed by spectroscopists. To determine the electron orbits Bohr introduced a quantum condition and to account for the relative brightness of spectral lines he added another rule which he called the correspondence principle. These developments and the Pauli exclusion principle are discussed in Chapters Vand VI. Chapter VII is entitled, "Intermez~o,Author's Warning t o the Reader." This is followed by "Act 11," consisting of seven chapters on the new Quantum Mechanics with which the names of de Broglie, Heisenherg, Dirac, and Schrtidinger are so intimstely connected, and the development of which depended on the discovery that electrons can also behave like waves. The author draws an analogy between "laundry lists" and matrices and attempts to explain in nonmathemrttical language the "momentous equation": h PXP-PXP-2-

Compared with the abstract ideas of Heisenherg and Dirac, Sohrtidinger's rl. seems to offer a more physical picture, since it used concepts already prevalent in the discussion of vibrating systems. All the different modes of attacking the problem of the behavior of atomic systems as well as the wave and particle concepts of both photons and electrons were finally unified by Heisenberg'sPrinciple of Indeterminary. The final conclusions, as italicised by the author, can he stated as follows: "There is simply no satisfactory way a t all of picturing the fundamental atomic processes of nature in terms of space and time and causality." Again, let us quote the author: "The quantum physicist does not know whether he knows what heis talking about. But thisat least he does know, that his talk, however incorrect i t may ultimately prove to be, is a t present immeasurably superior to thst of his classicalforehears, and bettor foundedin fact thanever before!' Of course, the discovery of the neutron, the positron, and the meson is mentioned, and also the phenomena of nuclear fission. Though the analogies, especially in discussing the "esoteric" ideas of Heisenberg rtnd Dirac, may occasionally rtppettrsomewhat forced, the author has not descended to the mysticism of either Jeans or Eddington. He bas in fact been very successful and in-

spiring in his attempt to present some of the concepts most di5cnlt to comprehend in a form that should give the lay reade (for whom the volume is intended) more than a "glimpse" into the philosophy of the subject. SAUL DUSHMAN Gannnar. E ~ a n z r cCOYPANT Soanan;cr*or. NEW YO==

A RATIONAL APPROACH TO CHEMICAL PRINCIPLES

J. A. Cmnston, Ledurer on Physical Chemistry, Royal Technical College, Glasgow. Blackia & Son, Ltd., London and Glasgow, 1947. xii r 211 pp. 37 figs. 3 3 tables. 8 X 5.5 cm. 5s. 6d. THISexcellent small volume abandons the historical approach to chemistry, starting with themost modern ideas of the structure of the atom. Other chapter headings are "The Arrangement of the Electrons," "The Gaseous State," "The Liquid State," "Dilute Solutions," "Mechanism of Chemical Comhination," "Energy of Chemical Comhination," "The Electrocbemical List," "Oxidation and Reduction," "Electrolysis," "The Law of Mass Action," "InEuence of Temperature and Pressure," "Heterogeneous Systems," and "Ionic Equilibrium." This text might he used in a very brief introduction to physical chemistry or as an auxiliary reading matter in qualitative analysis. S. B. ARENSON

1884 Lmsa' C A m o a B o a ~ v m o H o ~ ~ ~ w o Cazmonlur* oo,

THE CHEMISTRY AND TECHNOLOGY OF WAXES Albin H. Worth, Chemical Director, The Crown Cork and Seal Co., Baltimore, Maryland. Reinhold Publishing Corporation, New York, 1947. F n o a~ time long before Ulysses plugged the ears of his sailors with wax to keep them from going on the rocks a t the siren's call, wax has been an important item of commerce and tcchnology. It is surprising to find that during the past twenty years only two books in English, one of which is being reviewed, have appeared on the subject in spite of the fact that almost unlimited numbers of synthetic waxes and wax-like materials have been produced during this period and found their way into large tonnage applications. Warth has collected into one volume a large amount of information from scattered sources and is to he commended particularly on his extensive coverage of natural wares. Good descriptions are to be found of all the common waxes of commerce, beginning with the prototype beeswax; and large numbers of waxes of no commercial importance hut of interest and hearing on the subject, even to the wax from the tubercle bacillus are described. Odly, human ear wax has been overlooked although it features in folk medicine. Particularly to he commended is the discussion, brief as it is, of the metabolic processes leading to wax formation, and d s o the discussion on the ecology of waxes. These two sections show both how waxes are synthesized in the organism and why living organisms produce them. I t is interesting to 6nd thst waxes form an important part of cell walls, providing the necessary hlocksge to water and solute migration, and that the leafy surfaces of desert plants sre protected from excessive transpiration by wax, which may be in continuous films or in discreet particles and may accumulate to more than a millimeter thickness. Also, the leafy surfaces of plants in rainy areas are protected from the water by wax. Ample space is given to the very important mineral waxes obtained from fossil deposits of planta and from petroleum. If the hook has a weakness, it is probably that the treatment of synthetic waxes and wax-like compounds has been too brief, consistent with their technical and industrial importance. Although the natural waxes have physical and chemical properties

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varying through a considerable range, the synthetic products have so oxtended the range of properties as to open up new fields of application. Adequate treatment has been given emulsifable wax, waxy acids. and metallic soaos., as well as to methods for determinine the constants of waxes. Chapter 9 on wax technology serves more to suggest to the reader methods of application of waxes to specific problems than as a cookbook of reoipes and formulas. There is a useful table of physical .constants given in the Appendix. I t is the reviewer's opinion that the interest of the reader would have been served by the inclusion of more data in tabular form, and perhaps by the inclusion of more graphs, line drawings, and flow sheets in place of some of the photographs and the pen and ink drawings.

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8. 8. KISTLER

NORTON COYPANT WOBCEBTER, MABBACBDBETTB

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Archie G. Worthing a n d David Halliday, respectively, Professor and Assistant Professor of Physics at the University of Pittsburgh. John Wiley and Sons, Ino., New York, 1948. 245 figs. xii 522 pp. 15 X 23 cm. $6.

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T m s hook, written by two physicists, "includes material appropriate for s. first undergraduate course to follow an introductory course in physics and for an advanced course for college seniors and early graduate students." Chemists and engineers study much of the material contained in this book in courses in their departments, rather than in physics. Hence, this book is one that will be especially helpful to both student and instructor because of the emphasis given to experimental methods. Too frequently the student knows everything about a particular function, except how it could be determined in the'laboratory. The knowledge of the experimental methods gives a definite basis on which the theoretical ideas can be grounded. Many of the 245 figures illustrate diagrammatically experimental equipment for the subject being discussed. The 13 chapters found in the book are entitled: "Some Laboratory Procedures," "Temperature and Its Measurement," "The Expansivities of Solids and Liquids." "The Dynamical Theory of Heat.," "Calorimetry," "Specific Heats of Solids and Liquids," "Thermal Conduction of Solids and Liquids," "Thermal Properties of Gases," "Elementary Thermodynamics," "Change of Phase," "Heat Engines, Refrigerators, and Human Power Plants." "Conveotion." "Radiant Enerev." The ao-

mathemmttiesl functions. A number of innovations will he found in this hook, all aimed s t clarifying our present indefinite nomenclature. The verb "to mess" has been introduced to apply to the action when the analytical balance is used and 'the verb "to weigh" has been reserved for the use of the spring scales. The abbreviation "pd" is introduced for the mass pound and "lh" is reserved for the force pound. Such exactitude is not always followed, for the authors prefer to define the calory (sic) snd British thermal units in terms of the heat required to raise the temperature of water, &her than use the defined calorie or international steam table B.t.u., both of which are defined in terms of electrical units. Tho reviewer recommends this book to all instructors. whether

chemistry or engineering, whose courses discuss heat and its transformation and thermal properties. Graduate students interested in thermodynamics, and likewise men in industry, will find that this book will clarify many simple but hazy notions v have cancernine" heat and its behavior. that thev " m " KENNETH A . KOBE UNrvEnsnTr OP '

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CALCIUM AND PHOSPHORUS IN FOODS AND NUTRITION

Henry C. Sherman, Mitchill Professor Emeritus of Chemistry, Columbia University. Columbia University Press, New York, 1947. vi 176 pp. 12 tables. 7 figs. 14 X 22 cm. $2.75.

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CALCIUMand phosphorus are the most abundant mineral elements in the bodies of vertebrate animals. However, human infants are born calcium poor and must increase not only the m o u n t hut also the percentage of cdcium in their bodies to accomplish normal development. A tenfold concentration of the phosphorus content of the environment is called for in development of the vertebrate body. Plants contain their highest concentration of calcium in the leaves, while phosphorus tends to concentrate in the seeds. Cattle, living largely on the leafy parts of plants, may suffer from phosphorous deficiency, and man runs a risk of a ertleium shortage since h~ subsists largely on grains. With this background, the author considers the problems involved in the attainment of nutritional well-heing as it is determinrd by these mineral elements. The book is written from a strictly nutritional point of view and reviews in detail experiments on animals and humans that give data on the levels of intake of calcium and phosphorus that lead to their maximum retention in the growing individual and maintenance in adult life. The thesis that a condition of higher health, well above the merely adequate or passable, may be attained through nutrition is developed, as far as calcium is concerned, by a critical review of the well-known experiments of the author and his collaborators. In these experiments, a diet demonstrated to he adequate through sixty-two generations of rats, when further enriched by calcium led to higher vitality of the animals, especially as shown in breeding records, longer period before onset of senility and increased life expectancy. A chapter is devoted to the food sources of calcium and phosphorus and the influence of foods on the utilization of calcium and phosphorus. The author discusses the state of calcium in the blood and hone and the role of the hone traheculae in helping to maintain the ootimum calcium concentration in the blood. The chemical forms and functions of phosphorus in the body are summarized very briefly. An extensive selected biography of aver 500 titles gives ample references to the reader who desires to pursue in greater detsil and medical aspects of the subjeet. the Short as this book is, the reader will get from it a broad picture of the present knowledge of calcium and phosphorus in animal and human nutrition. He is given a vista of the benefit that may scoruo to the human race rts further understanding is aoquired, not only with respect to the mineral elements, but to other nutritional factors as well. F. A. CAJORI U m v e n s r r ~OF CoLonAoo Bcaaor, oP M l n l a s ~ DENVER. COLORADO