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BELL SYSTEM TECHNICAL JOCK SAL 



of the discussion. The principal one of these is the neglecting of 

 all reactions of second or higher order, thus leaving a set of linear 

 differential equations. 



Structure of the Vocal Tract 



The vocal tract consists of three principal parts, the lungs and 

 associated respiratory muscles for maintaining a flow of air, the 



EPIGLOTTIS 



FALSE VOCAL 

 CORDS 



GLOTTIS 

 VOCAL CORDS 



TRACHEA 



Fig. 1 — Anterior-Posterior Section of the Larynx. 



larynx (see Fig. 1) for producing the periodic modulation and the 

 upper vocal cavities, pharynx, mouth and nose for varying the rela- 

 tive harmonic content of sound originating in the larynx. 



