J. F. I. cylinders, and cone-cylinders moving at supersonic speeds, are presented by the Ballistic Research Laboratories and printed; however, the experimental apparatus employed is not explained, and the photographs are not adequately interpreted. Stress is placed upon the equation of continuity, momentum relation, and the energy equation. The illustrations are well chosen and reproduced. They both illustrate the basic principle and present to the reader the practical applications of the principle. Part II offers common illustrations and applications of fluid machinery, exemplifying the theories presented previously. The illustrations are generally confined to torque converters and pressure-raising devices, and do not cover all of the theory of Part I. Part III is an extension of Part I to unsteady flow, and flow in two dimensions. An analysis is made of the unsteady flow in mufflers, fan surging, water hammer, and certain fluid induction problems. The study of the two-dimensional flow of incompressible and compressible fluids is kept quite general. The mathematical techniques and analytical relations which are needed are carefully explained.
The author includes no illustrative problems in the book. Suggested problems average just over four per chapter. The value of the book would be enhanced for either reference or study if it contained more illustrative and suggested problems.
The wisdom of separating theory and application in an engineering textbook is always open to question. The decision may be based upon the complexity of the application or the Curriculum which must be followed. If l~art II of this book intends to illustrate and apply the material of Part I, then perhaps Part II has been limited to one branch of Mechanical Engineering when there was an opportunity to apply Part I to a larger area.
A. D. HAY SYNCHRONOUS MACHINES, THEORY AND PERFORMANCE, by Charles Concordia. 224 pages, 15 X 24 cm. New York, John Wiley & Sons, Inc., 1951. Price, $5.50. Electrical power engineers who design or use synchronous machines and systems and graduate students interested in a more detailed study of these machines will want this text.