126 Stimmer Studies of Birds and Books CHAP. 



reedy quality of the voices of most birds, for even 

 those of Blackbird and Blackcap, mellow as they 

 seem, will be found to have something of this quality 

 if we approach the birds quite closely. 



To make this point a little clearer I place side by 

 side a cut of the simplest form of oboe, and one of 

 the normal type of vocal instrument in a bird. 



FIG. A. 



FIG. B. 



In A the sound is produced by the reed affixed to the 

 small end of the instrument, which vibrates between 

 the lips of the player as he breathes air into it from 

 his lungs. The reed, I should say, is made of two 

 bits of very flexible wood fixed one on the other so 

 as to fit exactly ; these vibrate as the air from the 

 lungs passes through them, and this vibration is com- 

 municated to the column of air in the pipe of the 

 oboe. The result, if the instrument be constructed in 

 accordance with the principles of acoustics, is a true 

 musical sound. 



