46*2 Notices respecting New Books. 



coronal protuberance. Thus the radiated structure, and the irre- 

 gular and variable form of the corona would be accounted for. 



Cheltenham College, 

 October 21, 1878. 



LX. Notices respecting New Books. 



The Theory of Sound. By Johx William Steutt, Baron Ray- 

 leigh, M.A., F.R.S., formerly Fellow of Trinity College, Cam- 

 bridge. Volume II. London: MacMillan and Co. 1878. 8vo, 

 pp. 302. 



WE noticed the First volume of this work shortly after its pub- 

 lication (5th ser. vol. v. p. 66). The Second volume — which, we 

 presume, completes the work* — is now before us. We could not, 

 perhaps, give it higher praise than to say that it is worthy of its 

 predecessor. Not to speak of actual contributions to our knowledge 

 of the Theory of Sound which have been made by the author, it is 

 scarcely possible to overestimate the value to the student of a 

 perfectly trustworthy work which brings together the substance 

 of memoirs scattered through a variety of periodicals. Not fewer 

 than about a hundred and twenty or thirty memoirs are referred 

 to in the course of these volumes, most of which would be inac- 

 cesible to students living away from the chief centres of intel- 

 lectual activity. These, however, are not the only students who 

 are benefited by such a work as the present. Even those who 

 are more favourably situated rarely look at the memoirs unless 

 they are distinctly interested in their subjects at the time of 

 publication ; and this is particularly the case with memoirs on 

 such a subject as the Theory of Sound, the mere reading of which 

 may involve a considerable expenditure of time and labour. 



The subject of the present volume is Aerial Vibrations. In its 

 general method it resembles its predecessor. Thus, in the former 

 volume, the discussion of Vibrating Systems in general (chap. iv. 

 and v.) is preceded by a very careful consideration of a particular 

 case, viz. that of a system having one degree of freedom (chap, iii.) ; 

 so, in the present volume, the discussion of the general problem 

 of vibrations in three dimensions (chap. xiv. and xv.) is preceded 

 by that of the cases of Vibration in tubes (chap, xii.), and of some 

 other special problems, including the Reflection and Refraction of 

 Plane Waves (chap. xiii.). These four chapters, together with an in- 

 troductory chapter on "Aerial Vibrations " (chap, xi.), fill more than 

 half the volume. The remainder is divided into chapters on the 

 Theory of Eesonators (chap, xvi.), on Applications of Laplace's 

 Functions to Acoustical Problems (chaps, xvii. and xviii.), and on 

 Fluid Friction (chap. xix.). 



* The Work, as it stands, might certainly be accepted as a complete 

 treatise on what is generally understood by the Theory of Sound, viz. the 

 Kinetics of Acoustical Vibrations ; and we should have supposed the 

 work to be complete had not the publisher made himself responsible for 

 an announcement of Vol. iii., and also for a notice as to volumes subsequent 

 to the first. 



