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BELL SYSTEM TECHNICAL JOURNAL 



Physical Features of the Mouth-Pharynx System 



It is a curious fact that most of our data on the shape of the mouth 

 cavities, position of the tongue, etc., for producing the different vowel 

 sounds have been obtained by students of phonetics. There are of 

 course excellent drawings of the mouth structure, in a few typical 

 positions, given in the literature of anatomy; but for the finer differ- 

 ences, from one vowel sound to the next, we must rely on other sources. 

 I know of no determination, for example, of the actual volumes of the 

 mouth and pharynx, in any position for a typical individual, nor have 

 I succeeded, by consulting anatomical experts, in obtaining the desired 

 data. 



In Fig. 2, there are shown certain conventional drawings, in median 

 section, of the human mouth-pharynx region. These aie taken from 

 Rippmann's "Elements of Phonetics" (London, Dent, 1914) and were 

 taken in turn by Rippmann from an article by Dr. R. J. Lloyd. In 



Fig. 2— Diagrams of vocal cavities for various vowel sounds 



