350 Notices respecting New Books. 



Sfx in the infra-red. Quartz is practically transparent from the 

 ultra-violet to 1*8 /i. Tabulated data are given for allowing for 

 the effect of the absorption which enters beyond this point. The 

 results show that (within the errors of observation) in unpolarized 

 light, the transmission is not affected by the direction in which 

 the radiations pass through the material with respect to the optic 

 axis. 



The Science of Musical Sounds. By Prof. Dattof C. Miller, D.Sc 

 10s. 6d. net. New York : The Macmillan Co. London : Macniillan 

 & Co. Ltd., 1916. Pp. viii + 286. 



This work will be heartily welcomed by those who are fascinated 

 by the various problems and methods of harmonic analysis and 

 its applications in connexion with musical souuds. It presents, 

 substantially as given, a course of eight experimental lectures 

 delivered by the author at the Lowell Institute during January 

 and February 1914. As befits a course of lectures intended for a 

 general audience, the subject matter consists in large part of 

 elementary and familiar material, but selected and arranged to 

 develop the main purpose. But, in accordance with the design 

 of all such lectures at the Lowell Institute, however elementary 

 their foundation, they meet the legitimate expectation that they 

 shall include the most recent progress of the science under review 

 and experimentally illustrate this to the fullest possible extent. 

 It is somewhat difficult to adequately present in book form this 

 demonstration aspect of a course of lectures. But in this case 

 the lavish use of diagrams and photographs of special apparatus 

 and their records, or of arrays of forks, pipes, &c, leaves nothing 

 to be desired. 



After two preliminary lectures on waves, vibrations, and tones, 

 we have a lecture devoted to methods of recording sound waves. 

 After passing in review the time-honoured methods, the author 

 introduces his own deAace the jolwnodeiJc or sound-demonstrator. 

 This consists essentially of, a horn and glass diaphragm for re- 

 ceiving the sound, and a connected mirror for demonstrating its 

 amplitude, frequency, and quality. The mirror has a few silk 

 fibres from the diaphragm passed once round its axle and then 

 held tight by a spring. The light reflected from the mirror may 

 be used for demonstration purposes or for yielding permanent 

 photographic records. 



The next lecture deals with the analysis and synthesis of har- 

 monic curves, the fifth with the influence of the horn and 

 diaphragm on the sound waves. The sixth and seventh lectures 

 are occupied respectively with the tone qualities of musical instru- 

 ments and of vowels. 



The history of theories of vowel sounds is given clearly and 

 compactly. It is interesting to note that the results of the 

 author's work here described are in entire agreement with the 

 fixed-pitch theory of vowels due to Helmholtz. 



