THEORIES OF VOWEL TONES. 



1219 



flame apparatus. This method is useful, because it shows the different 

 forms of the sound-wave, without change of period, corresponding to a 





Fig. 432. — KiJnig's apparatus for illustrating the quality of vowel 

 tones by a manometric flame. 



tone of determinate pitch, when the vowels are sung upon that tone. 

 The apparatus is shown in Fig. 432. 



Fig. 433.— Flame pictures of the vowels OU, 0, and A. — Kiinig. 



The next figure shows the forms taken by the flame when the three 

 notes ut v sol v and ut, are sung with the vowels A, 0, and OU. 



