450 PHYSIOLOGICAL PHYSICS. [Chap. xxxm. 



the production of one vowel the mouth will act as 

 resonator for a particular harmonic, and for the pro- 

 duction of another vowel a new form will be given to 

 it for the reinforcement of a different overtone of the 

 vibrating cord. This may be shown with the aid of 

 Koenig's manometric flames already described. An 

 analysis so conducted has revealed differences in 

 the vowel sounds, which may be briefly stated as 

 follows : 



" The vowel A contains, besides the fundamental 

 note, the second harmonic feeble, the third strong, 

 and the fourth feeble ; 



" E has the fundamental note feeble, the second 

 harmonic rather strong, the third feeble ; on the other 

 hand, the fourth is very strong and the fifth feeble ; 



" i has very high harmonics, especially the fifth, 

 strongly marked ; 



" o contains the fundamental note, the second 

 harmonic very strong, and the third and fourth har- 

 monics slightly ; 



"u is composed of the fundamental note very 

 strong, and the third harmonic sufficiently pro- 

 nounced." 



Thus it is evident that a knowledge of the 

 physics of sound is necessary for a proper appreciation 

 of the action of the ear in perceiving sounds, and of 

 the action of the vocal apparatus in producing 

 sounds. 



