490 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1924 



the characteristics of which are largely determined by the individ- 

 uality of the speaker. In general, the fundamental or lowest tone 

 of the vibration is rather low in pitch and somewhat lower for men 

 than for women. The mouth and throat cavities, modified by the 

 shape and position of the tongue and lips, act as resonators to re- 

 enforce and amplify the relative strength of various harmonics. In 

 this way the shape and position of the mouth and tongue determine 

 largely the particular voAvel spoken. The vowel " u " at the upper 

 left of the triangle is formed by rounding the lips, drawing back the 

 tip of the tongue, and raising it at the back in such a way that the 

 throat is almost closed off and the mouth is formed into a single 

 large resonant cavity. Overtones of the cord vibration in the vi- 

 cinity of about 300 cycles are strongly reenf orced. As we come down 

 the left-hand side of the triangle, pronouncing the sounds indicated, 

 the lip opening widens and the jaw is lowered. The tongue is still 

 raised at the back, and we have single resonance until the bottom 

 point of the triangle is reached. In pronoimcing the sounds " a '' 

 and " a " the lips are wide open. With the former the jaw is 

 dropped, the tongue is only slightly raised at the back, and the most 

 prominent reenforcement is in the neighborhood of 1,000 cycles. 

 With the latter the tongue lies flat in the mouth, and the mouth and 

 throat form connected cavities of nearly equal size. There is double 

 resonance, the two reenforced tones lying in the region from about 

 800 to 1,200 cycles. As the vowels on the right hand side of the tri- 

 angle are pronounced starting upward from "a," the separation of 

 the lips becomes smaller, the tongue is raised in the center, and then 

 further forward. These vowels are all characterized by double reso- 

 nance. With the sound " e " the lips are drawn to form a wide slit, 

 the tongue is raised in front until its ridge is closely opposite the 

 roof of the front of the mouth. The tongue is drawn forward so 

 that the back of the mouth and the throat form a large resonant 

 chamber. The small tubular space over the tongue at the front 

 leads from the larger space to the exit at the lips. The two fre- 

 quency regions, which are characteristic of the sound " e," are in the 

 vicinities of 300 and 2,500 cycles. 



The transition vowels or diphthongs are those formed by passing 

 from one vowel to another. For example the sound " i " is pro- 

 nounced by forming the mouth as if to say "a" and then rapidly 

 passing to the sound " e." Similarly, the sound designated by the 

 letter " w " is made by forming the mouth as if to say " u " and then 

 passing suddenly to any of the other pure vowels. 



Ordinarily when pronouncing a vowel the glottis opens gently at 

 the beginning of the sound, and the controlled passage of breath 

 produces the sound. If the vocal cords are separated initially in 

 such a way that the glottis is open and the sound is begun by a rather 



