Dr. R. Konig on Manometric Flames. 13 



and note with different intensity. A very slight change in the 

 condition of the voice is sufficient to effect great changes in 

 the flame- pictures. For instance, when my throat is weary, 

 instead of obtaining the picture as drawn of U sung on e, I get 

 only a small flame and two tall broad ones, the last in place of 

 two and two in the picture ; and similar simplifications are made 

 in all the flame-groups. 



In order to see first what influence may be expected from the 

 fixed notes of the mouth- cavity on the flame-pictures, I will give a 

 general view by drawing for each vowel, sung in each note of the 

 two octaves from C to c, the harmonic overtone to which the 

 characteristic note approximates, and the number of vibrations by 

 which they differ. 



For 0, A, and E, I take the characteristic notes (given by 



Helmholtz) b, b, andZ>; but, differing from the former opinion 

 of Donders and Helmholtz, I have found for XJ and I the notes 



b and b ; so that the five chief vowels are all an octave distant 

 from each other, and the characteristic note of the lowest vowel, 

 viz. XJ, unites with the lowest note which it is possible for the 

 mouth to intensify by resonance. 



In the definition of these notes there is no question of an ab- 

 solutely exact number of vibrations. If, for example, I find the 

 most powerful resonance of the mouthpiece for U giving between 

 220 and 230 vibrations, I may take equally 224 or 225 vibra- 

 tions as the characteristic note of U. I make this remark 

 here particularly because, in a short address to the Paris Aca- 

 demy (April 25, 1870) on the before-mentioned definitions of 

 the characteristic notes of U and I, I gave as the average simple 

 vibrations for U, 0, A, E, I, 225, 450, 900, 1800, and 3600— 

 but after a subsequent revision^ the equally correct numbers 224, 

 448, 896, 1792, and 3584. The former are indeed easier to 

 retain, but they refer to no note in use; whereas the latter 

 numbers show the vibrations of the seventh overtone of C v 



C, c, c, and c (c = 256 vibrations.). 



In the following Table the first column contains the vowel, 

 the second the note sung, and the third and fourth the two 

 overtones of the sound of that note between which the cha- 

 racteristic sound of the vowel falls, together with the number of 

 vibrations by which one of these notes is lower and the other 

 higher than the proper ^ote of the mouth-cavity. 



