Abstracts of Recent Technical Books and Papers 

 from Bell System Sources 



Theory of Vibrating Systems and Sound. I. B. Crandall. Recent 

 years hiive witnessed a great revival in Acoustics, both as a subject 

 of industrial research and as a field for academic cultivation. This 

 development has been carried on most actively in America and in 

 Germany, and has been measurably due to the demands of the public 

 for commercial acoustic devices in the public address and radio fields. 

 In addition, there has evolved the new subject of Architectural 

 Acoustics, largely through the researches of the late W. C. Sabine 

 and his followers in this country. 



In this situation, with an ever increasing body of technical litera- 

 ture, it may be noted that the standard textbooks on Sound have 

 maintained their classical character, although new impedance methods 

 and terminology have come into use (closely parallel to those of elec- 

 trical theory) and many new fields of study have been opened up. The 

 need for a connected treatment involving the new subject matter 

 and methods the present author has attempted to supply, and while 

 necessarily building on the classical treatises as a foundation, he has 

 included a chapter on complex vibrating systems with a treatment of 

 acoustic filters; two chapters on the theories of sound generation and 

 radiation with applications to tubes and horns and a chapter on the 

 essentials of architectural acoustics and absorbing materials. An 

 extended bibliographic appendix serves as an entry to many branches 

 of Applied Acoustics — ^for example, loud speaking telephones, piezo- 

 electric resonators, recent work on speech and hearing, and sub- 

 marine signalling, to cite only a few examples. 



The author has purposely avoided duplicating classical material 

 such as the theories of bars or of Fourier's series, feeling that the 

 newer ideas and developments deserve the emphasis gained thereby. 



The book aims to organize Acoustics as now practiced, and research 

 workers will probably find it useful, not only in their classes, but as a 

 starting point for acoustic research. 



The book is produced by D. Van Nostrand & Co. ($5.00). 



Contemporary Physics. Karl K. Darrow. During the twenty- 

 five years since this century began, the science of physics has under- 

 gone amazing enlargements and transformations which may well be 

 ranked among the most significant attainments of our times. Through 



652 



