10 ART. 10. T. TERADA. 



The pitch for each position varies of courèe with different widths 

 of the opening of the embouchure, with the pressure of the breath, 

 and also with the degree of the opening of the finger-holes. In 

 the above table, the fundamental tone was obtained by a very 

 light breath-pressure in order that it might not deviate much 

 from the natural pitch ; on the contrary, the overtone can be 

 obtained only by somew^hat strong pressure. When blown forcibly 

 as in actual playing, the fundamental tone is raised about a 

 semitone so that the overtones for the positions 1, 2, 4, 8, 10, 

 17, 30, 31, 32 become the octaves of the corresponding funda- 

 mental tones. It will be noticed that the overtones of the other 

 positions are very much complicated with respect to their funda- 

 mental notes. While the fundamental notes are generally lowered 

 more or less by closing the hole below the uppermost open one, 

 the contrary is often the case with the overtones as in the 

 positions 5, 7, 9, 10, 12, etc. Besides, an overtone much lower 

 than the octave is met with in the position 9 and 18. 



2. Correction for the Mouth. 



How much the natural pitch of the pipe is influenced by 

 varying the area of the mouth-opening may be shown by the 

 following simple experiment. The embouchure is brought to the 

 lip, as in playing. Bring a pro])er vibrating tuning fork near 

 the embouchure and adjust the aperture so that the resonance 

 is maximum. If the pipe be slightly inclined from this position 

 or if the lower lip be slightly moved, the resonance at once falls. 



For an ordinary organ pipe of a circular section, the correc- 

 tion which is to be added to its leno'th in order to obtain the 

 fractions of the wave length, is according to Cavaille-Coll, 3^ R, 



