Ill 



PROBATION AND ARTICULATION 



163 



Sauberschwartz with Griitzner (1895) investigated the subject 

 by an ingenious application of the laws of the interference of 

 sounds. The vowels were sung into the mouthpiece of a long 

 tube, to which other short tubes of definite length were attached. 

 By closing the outer end of certain of these tubes various partials 

 could be extinguished by interference, and the listener at the 

 other end of the tube observed an alteration in the quality of 

 the vowel. Sauberschwartz, generally speaking, supports Hermann. 



Later researches by Boeke, M'Kendrick and others added 

 new facts to the analysis of vowel sounds. At the Fifth 

 International Physiological Congress at Turin, Hensen stated 

 that the resonance tones of the oral cavity arranged for the 

 pronunciation of different vowels are variable within certain 

 limits, as had been established by Pipping. But he also showed 

 that the pitch of the laryngeal tones produces a rise in the oral 

 resonance tones. At a they may rise from 940 to 1175 ; at o 



FIG. 104. Pitch of the vowels according to Hermann. 



from 498 to 552 double vibrations. The problem of vowel sounds 

 is therefore more complicated than was supposed, and still awaits 

 its final solution. 



In conclusion, Bonders' theory, which assumes that the oral 

 cavity is tuned for each vowel to a tone of fixed and unalterable 

 pitch, whatever the fundamental laryngeal note to which it is 

 sung, is certainly too restricted. Each vowel, however, undoubtedly 

 has one or more predominating partial tones, formed by the oral 

 cavity, on which the specific character of that vowel depends. Since 

 the form of the mouth varies with the individual and the race, and 

 the positions it assumes in different dialects and even in different 

 individuals in the pronunciation of the several vowels are not 

 and cannot be identical, it is easy to see why the formants of 

 any vowel are not identical in all cases. They approximate, 

 however, in certain common characters, by which it is possible 

 to identify a vowel, however differently it may be formed by 

 different individuals. It is also certain that the resonating 

 cavity varies very little when a musical scale is sung to a single 

 vowel. The ear is always able to recognise the vowel sung, 

 whatever its pitch ; each vowel, however, has a special register 

 in which its quality is best ; the soprano is best adapted to the 



