terms used. Here the definition of the Amagat unit is not consistent with that previously given in the text and is not corPect. All workers who use the equipment and techniques of high pressure will want this book. I t gives many references to the literature a n all phases of the work. It will be used as a corollary text in thermodynamics and technology. KENNETH A. KOBE U ~ l v s n a r ~orr T s x ~ s AUSTIN. T m h s
MOLECULAR FLOW OF GASES G. N. Patterson, Director, Institute of Aerophysics, Chairman, Department of Aeronautical Engineering and Aerophysics, School of Graduate Studies, University of Toronto. John Wiley 6r Sons, Inc., New York, 1956. x 217 pp. 67 figs. 1s X 23.5 cm. $7.50. Tnrs hook desls with the transition from the macrosoopic phenomenological continuum approaoh to the microscopic moleoular-kinetic approach in the mathematical theory of gases in motion. The molecular point of view has proved indispensable to the understanding of such topios as the slip flow of a highly rarefied gas, or the relaxation effects associated with a strong shock wave. The moleculsr model assumed is that of spherical molecules obeying Maxwell's distribution law, or, in the case of non-isentropic flow, of molecules aoting as spherically symmetrical point centers of force, with a small modification of Maxwell's law. The mathemetical development is complete therefore only for a. monatomic gas, hut can be applied with suitable modifications to diatomic gases. The book is divided into five chapters. Chapter I presents the derivation of the Boltamann equation from the study of a generalized collision between two hardsphere molecules and the basic equations for the molecular transport of mass, momentum, and energy. Chrtpter 11, on isentropic flow, solves the Boltzmann equation for the case in which molecular collisions no longer affect the velocity distribution, t o obtain Maxwell's law, and proves that the flow of a Maxwellisn gas is isentropic. This chapter further discusses the speed of sound, specular reflection from a solid boundary, and expansion waves for one dimensional unsteady flow and two-dimensional steady flow. Chapter I11 develops the tbeoreti d foundation for the case of nonisentropic flows, with small deviations from Maxwell's law, by developing the velocity distribution function for malecules whose collisions can be treated as encounters between spherically symmetrical point centers of force. I t then develops the basic transport equations for such molecules. Chapter IV, on nonisentropic flows, reviews experimental data. on viscosity and heat conduction and investigates the properties of two nonisentropic "layers": the shock front, and the boundary layer adjacent to a solid wall. It closes with a brief discussion of the effects of the internal degrees of freedom of di- and poly-atomic molecules. (Continued on Page A78)
+
VOLUME 34, NO. 2, FEBRUARY, 1957
Chapter V, on the mechanics of rarefied gases, deals with transport effects in the free-molecule flow of gases. Three appendixes, on mathematied aids, on diffel; ential equations and their characteristics (a valuable summary) and on the basic equations of motion of a gas, close the work. The book is intended for physicists and engineers. English units are used in many applications of the theory. To many readers, this volume will present a formidable appearance: 844 numbered equations, plus many unnumbered, in 214 pages of text. The mathematics, however, is not beyond the competence of anyone who has had a course in theoretical physics. The figures are clearly and neatly drawn. The t,vpography is good and pleasing in appearance. A glossary of symbala, a t the close of each chapter, is definitely helpful. The main interest of the work, to chemists, lies in the proof it supplies of the importance of the laws of molecular behavior to the theory of such ultra-modern events as supersonic flight and the p~.opagatianof shock naves. AND&
J. d
e
~
Bosrol- Comeoz C n ~ s l s n rH,L&, M * s ~ * c " " ~ E T T E ~
HISTORY OF .CHEMISTRY IN ANCIENT AND MEDIEVAL INDIA Edited by Priyodoronjan Roy, Indian Association for the Cultivation of Science, Calcutta. Indian Chemical Society, Calcutta, 1956. xviii 494 pp. 39 figs. 1 table. 16 X 24 cm. $6.
+
PROFESSORRAY,in his carefully ronstrueted revision of Prafulla Chandra Ray's standard "History of Hindu Chemistry," has given us a highly informabive and interesting description of Indian chemistry. In chronological order, the contributions of Indians to chemistry have been recarded from the Harappa period of the fourth millennium B.C. to the end of the Mogul culture. The theoretical aspects as well as the practical arts of ancient Indian chemistry have been given full treatment in addition to discussion of social and cultural conditions concomitant with ancient chemical development. Of value for those interestedin the-history of chemical technology, Ray discusses the a r t of making glazed pottery, the extraction and working of metals and alloys, preparation of caustir alkalies, oxides and sulfides of metals and other substsnces. Some other representative topics are the genesin of the infraatomic unit potentials, chemistry in the medical schools of ancient India, chemistry of colors, atomic theory of the Buddhists, and the theory of atomic eombination. Many of the ideas deserihed make delightful reading for the average chemist n-ith a historical bent. The scholar in the history of science will find equally rewarding the inclusion of tests in the original Sanskrit and transcriptions from Tibetan xylographs and (Conlinwd m Page A80) JOURNAL OF CHEMICAL EDUCATION
*
~
