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Measurement techniques in mechanical engineering
480
BOOK R E V I E W S
and pneumatic control circuits and control units. The author goes into the greatest detail in the consideration of the heating phase of air conditioning. Separate chapters are devoted to the control of domestic heating, commercial heating, and radiant-panel heating. Other chapters are devoted to the control of ventilation, cooking, humidification, and refrigeration.
Automatic Control of Heating and Air Conditioning is intended to be an elementary textbook, not an advanced technical treatise. It is directed neither at the service man nor the mathematician. Instrument manufacturers have booklets for the service men, while the publisher carries a series of books entitled "Instrument Engineering" which considers the operation of instruments from the mathematical point of view. Mr. Haines directed this book toward the air conditioning student and the application engineer. All methods of control which are generally used are illustrated and described. Their advantages and limitations are discussed. The illustrations are excellent, and these alone are worth the cost of the book. Several new and accurate sensing devices and circuits have recently been developed and placed on the market. They were omitted from this book possibly because the author wished to be conservative. Because this is an introductory textbook in an important field not previously covered, and because it is well written and well illustrated, the reviewer wishes to recommend it as an essential textbook for the beginner, and as an excellent reference book for the application engineer in the field of automatic controls. A. D. HAY LUMINESCENCE AND THE SCINTILLATION COUNTEa, by S. C. Curran. 219 pages, diagrams, 15 X 22 cm. New York, Academic Press, Inc.; London, Butterworth's Scientific Publications; 1953. Price, $5.80. The scintillations produced in a zinc sulfide screen when struck by alpha particles or protons were widely used in the early studies of nuclear phenomena. The method fell into disuse because the scintillations had to be observed by eye and counted manually. About a decade ago the method gained new prominence when automatic counting of the scintillations by photomultipliers and elec-
[.1. F. I.
tronlc counters was introduced. This book summarizes this decade of work. This modern scintillation counter consists of a suitable luminescent material to produce a flash of light (usually visible or near ultraviolet) when struck by a particle or quantum of electromagnetic radiation, a photomultiplier to detect the flashes, and suitable circuits for counting and measuring the pulses produced by the photomultiplier. Two introductory chapters outline the counter and those aspects of the interaction between radiation and matter which are of importance to this subject. The remainder of the book is largely concerned with discussions of the three components of the counter mentioned above. A fairly complete description of photomultipliers with particular emphasis on important operating characteristics is given After an introduction to the theory of luminescence the preparation, properties, and important operating characteristics of useful luminescent materials are described. As in the discussion of photomultlpllers the emphasis here is on practical aspects of scintillators as used in counters. Final chapters deal with applications of scintillation counters to the study of radiation of various types and the circuits used for recording the pulses. The book is well illustrated and contains both author and subject indexes. It thus provides a very good guide to the use of scintillation counters. E . R . STEPHENS MEASUREMENT TECHNIQUES IN MECHANICAL ENGINEERING, by R. J. Sweeney. 309 pages, diagrams, 16 X 24 cm. New York, John Wiley & Sons, Inc., 1953. Price, $5.50. Devices and techniques to measure various mechanical properties are generally described in books on the various fields of mechanical engineering. Devices to measure electricity are found in books on electricity; those to measure temperature, in books on heat; and so on. Special papers are often devoted to specific measuring devices. It is seldom, if ever, that one finds a book concerned solely with all types of measuring devices and techniques in the field of mechanical engineering, exclusive of those for materials testing and experimental stress analysis. Such a book however, is Measurement Techniques in Me-
Nov., I953.]
BooI~ REviEws
chanical Engineering by R. J. Sweeney, a consulting engineer with considerable teaching and industrial experience. By providing a description of such a wide variety of measuring instruments together with their usage under one cover, this book should be of much value to the engineering profession. Beginning his book with a discussion of measurement, including instrument factors, installation errors, selection of instruments and instrument control systems, Mr. Sweeney proceeds to discuss mensuration and the various instruments to record mass, time and speed, and electricity. Dynamometers, various pressure gages, instruments to determine temperature, instruments to measure fluid flow are next described. The book concludes with a discussion of steam and fuel colorimeters, methods of chemical analysis of gases, water and coal and a final chapter on automatic controls. E . W . HAMMER
DIELECTRICAERIALS, by D. G. Kiely.
132 pages, 11 X 17 cm. Methuen's Monographs on Physical Subjects. New York, John Wiley & Sons, Inc. ; London, Methuen & Co., Ltd.; 1953. Price, $2.00. During and immediately after World War II there was carried out intensive theoretical and experimental research in the use of hollow metal waveguides. But little attention was given, until recently, to the possible use of dielectric rods, hollow tubes and horns as energy carriers and radiators. One reason for this lag may be the relative complexity of problems pertaining to dielectric radiators. The field is too new to justify a textbook on the subject. This monograph collects the scattered literature, presents a general review of existing theoretical and experimental work concerned with radiation pattern characteristics, derives mathematical expressions for them, and points out directions in which additional theoretical and experimental work should be done. The volume serves its purpose well as a critical review of the field allowing the reader to obtain a broad picture of present developments with comparatively little expenditure of effort. The subject matter is presented in four chapters concerned with propagation along a dielectric rod, and the properties of rod, tube and horn radiators. The first of these chapters is, of course, basic. Starting with Max-
48I
well's equations, the E and H field distributions are developed for circular and non-circular symmetric waves. Once the field configuration is known, the rod can be excited. It is fortunate indeed that the required configuration is similar to that present in a hollow metal waveguide. This allows the dielectric rod to be excited merely by inserting it into the end of a hollow metal guide. At the present time no wholly satisfactory theory has been developed to analyze the radiation pattern characteristics of dielectric antennas in such a way as to explain fully the experimentally observed phenomena wherein the main lobe of the pattern is directed along the rod and its directivity is proportional to the length of the rod. Three theoretical methods are reviewed and compared to explain the observed results: the first uses Huygen's principle and ray theory ; the second uses a wave-length lens approach; and the third, and most advanced, method uses the Schelkunoff equivalence principles. The chapters devoted to tubes and horns review derivations of field configurations and their dependencies on parameters of the problem. Physicists and engineers who are concerned with the design of centimetric radiators would do well to read this monograph. Some of the design data may be directly applicable to their work. The new problems pointed out by the author should no doubt spur additional research in this field. S. CHARP THE FURANS, by A. P. Dunlop and F. N. Peters. ACS Monograph No. 119. 867 pages, diagrams, 16 X 24 cm. New York, Reinhold Publishing Co., 1953. Price,
$18.00. About thirty years ago, when furfural was first obtained from oat hulls, a new field was opened in organic chemistry. As more and more research was carried on, there was much interest expressed by industry. Keeping pace with the growth of research in furan compounds was the literature. As a result, the need for a summarization of the research and of the industrial uses became urgent and important. Two men who had done so much of the early work with furfural and who have concerned themselves with the theoretical aspects and commercial problems are Dr. F. N. Peters and Mr. A. P. Dunlop. They
BOOK R E V I E W S
and pneumatic control circuits and control units. The author goes into the greatest detail in the consideration of the heating phase of air conditioning. Separate chapters are devoted to the control of domestic heating, commercial heating, and radiant-panel heating. Other chapters are devoted to the control of ventilation, cooking, humidification, and refrigeration.
Automatic Control of Heating and Air Conditioning is intended to be an elementary textbook, not an advanced technical treatise. It is directed neither at the service man nor the mathematician. Instrument manufacturers have booklets for the service men, while the publisher carries a series of books entitled "Instrument Engineering" which considers the operation of instruments from the mathematical point of view. Mr. Haines directed this book toward the air conditioning student and the application engineer. All methods of control which are generally used are illustrated and described. Their advantages and limitations are discussed. The illustrations are excellent, and these alone are worth the cost of the book. Several new and accurate sensing devices and circuits have recently been developed and placed on the market. They were omitted from this book possibly because the author wished to be conservative. Because this is an introductory textbook in an important field not previously covered, and because it is well written and well illustrated, the reviewer wishes to recommend it as an essential textbook for the beginner, and as an excellent reference book for the application engineer in the field of automatic controls. A. D. HAY LUMINESCENCE AND THE SCINTILLATION COUNTEa, by S. C. Curran. 219 pages, diagrams, 15 X 22 cm. New York, Academic Press, Inc.; London, Butterworth's Scientific Publications; 1953. Price, $5.80. The scintillations produced in a zinc sulfide screen when struck by alpha particles or protons were widely used in the early studies of nuclear phenomena. The method fell into disuse because the scintillations had to be observed by eye and counted manually. About a decade ago the method gained new prominence when automatic counting of the scintillations by photomultipliers and elec-
[.1. F. I.
tronlc counters was introduced. This book summarizes this decade of work. This modern scintillation counter consists of a suitable luminescent material to produce a flash of light (usually visible or near ultraviolet) when struck by a particle or quantum of electromagnetic radiation, a photomultiplier to detect the flashes, and suitable circuits for counting and measuring the pulses produced by the photomultiplier. Two introductory chapters outline the counter and those aspects of the interaction between radiation and matter which are of importance to this subject. The remainder of the book is largely concerned with discussions of the three components of the counter mentioned above. A fairly complete description of photomultipliers with particular emphasis on important operating characteristics is given After an introduction to the theory of luminescence the preparation, properties, and important operating characteristics of useful luminescent materials are described. As in the discussion of photomultlpllers the emphasis here is on practical aspects of scintillators as used in counters. Final chapters deal with applications of scintillation counters to the study of radiation of various types and the circuits used for recording the pulses. The book is well illustrated and contains both author and subject indexes. It thus provides a very good guide to the use of scintillation counters. E . R . STEPHENS MEASUREMENT TECHNIQUES IN MECHANICAL ENGINEERING, by R. J. Sweeney. 309 pages, diagrams, 16 X 24 cm. New York, John Wiley & Sons, Inc., 1953. Price, $5.50. Devices and techniques to measure various mechanical properties are generally described in books on the various fields of mechanical engineering. Devices to measure electricity are found in books on electricity; those to measure temperature, in books on heat; and so on. Special papers are often devoted to specific measuring devices. It is seldom, if ever, that one finds a book concerned solely with all types of measuring devices and techniques in the field of mechanical engineering, exclusive of those for materials testing and experimental stress analysis. Such a book however, is Measurement Techniques in Me-
Nov., I953.]
BooI~ REviEws
chanical Engineering by R. J. Sweeney, a consulting engineer with considerable teaching and industrial experience. By providing a description of such a wide variety of measuring instruments together with their usage under one cover, this book should be of much value to the engineering profession. Beginning his book with a discussion of measurement, including instrument factors, installation errors, selection of instruments and instrument control systems, Mr. Sweeney proceeds to discuss mensuration and the various instruments to record mass, time and speed, and electricity. Dynamometers, various pressure gages, instruments to determine temperature, instruments to measure fluid flow are next described. The book concludes with a discussion of steam and fuel colorimeters, methods of chemical analysis of gases, water and coal and a final chapter on automatic controls. E . W . HAMMER
DIELECTRICAERIALS, by D. G. Kiely.
132 pages, 11 X 17 cm. Methuen's Monographs on Physical Subjects. New York, John Wiley & Sons, Inc. ; London, Methuen & Co., Ltd.; 1953. Price, $2.00. During and immediately after World War II there was carried out intensive theoretical and experimental research in the use of hollow metal waveguides. But little attention was given, until recently, to the possible use of dielectric rods, hollow tubes and horns as energy carriers and radiators. One reason for this lag may be the relative complexity of problems pertaining to dielectric radiators. The field is too new to justify a textbook on the subject. This monograph collects the scattered literature, presents a general review of existing theoretical and experimental work concerned with radiation pattern characteristics, derives mathematical expressions for them, and points out directions in which additional theoretical and experimental work should be done. The volume serves its purpose well as a critical review of the field allowing the reader to obtain a broad picture of present developments with comparatively little expenditure of effort. The subject matter is presented in four chapters concerned with propagation along a dielectric rod, and the properties of rod, tube and horn radiators. The first of these chapters is, of course, basic. Starting with Max-
48I
well's equations, the E and H field distributions are developed for circular and non-circular symmetric waves. Once the field configuration is known, the rod can be excited. It is fortunate indeed that the required configuration is similar to that present in a hollow metal waveguide. This allows the dielectric rod to be excited merely by inserting it into the end of a hollow metal guide. At the present time no wholly satisfactory theory has been developed to analyze the radiation pattern characteristics of dielectric antennas in such a way as to explain fully the experimentally observed phenomena wherein the main lobe of the pattern is directed along the rod and its directivity is proportional to the length of the rod. Three theoretical methods are reviewed and compared to explain the observed results: the first uses Huygen's principle and ray theory ; the second uses a wave-length lens approach; and the third, and most advanced, method uses the Schelkunoff equivalence principles. The chapters devoted to tubes and horns review derivations of field configurations and their dependencies on parameters of the problem. Physicists and engineers who are concerned with the design of centimetric radiators would do well to read this monograph. Some of the design data may be directly applicable to their work. The new problems pointed out by the author should no doubt spur additional research in this field. S. CHARP THE FURANS, by A. P. Dunlop and F. N. Peters. ACS Monograph No. 119. 867 pages, diagrams, 16 X 24 cm. New York, Reinhold Publishing Co., 1953. Price,
$18.00. About thirty years ago, when furfural was first obtained from oat hulls, a new field was opened in organic chemistry. As more and more research was carried on, there was much interest expressed by industry. Keeping pace with the growth of research in furan compounds was the literature. As a result, the need for a summarization of the research and of the industrial uses became urgent and important. Two men who had done so much of the early work with furfural and who have concerned themselves with the theoretical aspects and commercial problems are Dr. F. N. Peters and Mr. A. P. Dunlop. They