808 VOICE AND SPEECH [CH. LVII. 



The pitch of the Vowels has been estimated musically ; u has the lowest pitch, 

 then o, a (as in father), a (as in cane), , and e. We may give a few examples of 

 the shape of the resonating cavities in pronouncing vowel sounds, and producing 

 their characteristic timbre : when sounding a (in father) the mouth has the shape of 

 a funnel wide in front ; the tongue lies on the floor of the mouth ; the lips are wide 

 open ; the soft palate is moderately and the larynx slightly raised. 



In pronouncing u (oo), the cavity of the mouth is shaped like a capacious flask 

 with a short narrow neck. The whole resonating cavity is then longest, the lips 

 being protruded as far as possible ; the larynx is depressed and the root of the tongue 

 approaches the fauces. 



In pronouncing o, the neck of the flask is shorter and wider, the lips being 

 nearer the teeth ; the larynx is slightly higher than in sounding oo. 



In pronouncing e, the flask is a small one with a long narrow neck. The 

 resonating chamber is then shortest as the larynx is raised as much as possible, and 

 the mouth is bounded by the teeth, the lips being retracted ; the approach of the 

 tongue near the hard palate makes the long neck of the flask. 



The Consonants are produced by a more or less complete closure of certain 

 doors on the course of the outgoing blast. If the closure is complete, and the blast 

 suddenly opens the door, the result is an explosive ; if the door is partly closed, and 

 the air rushes with a hiss through it, the result is an aspirate ; if the door is nearly 

 closed and its margins are thrown into vibration, the result is a vibrative ; if the 

 mouth is closed, and the sound has to find its way out through the nose, the result 

 is a resonant. 



These doors are four in number ; Briicke called them the articulation positions. 

 They are 



1. Between the lips. 



2. Between the tongue and hard palate. 



3. Between the tongue and soft palate. 



4. Between the vocal cords. 



The following table classifies the principal consonants according to this 

 plan : 



Articulation 

 position. 

 1 

 2 

 3 

 4 



The introduction of the phonograph has furnished us with an instrument which 

 it is hoped in the future will enable us to state more accurately than has hitherto 

 been possible, the meaning of the changes in nature and intensity of the complex 

 vibrations which constitute speech. The microscopic study of the tracing on the 

 recording phonographic cylinder, and various methods of obtaining a high magnifi- 

 cation of the movements of the recording style have been carried out by M'Kendrick 

 and others. The subject is, however, not yet sufficiently ripe for definite statements 

 to be made. 



Defects of Speech. 



Speech may be absent in certain forms of lunacy, and temporarily in that defect 

 of will called hysteria. 



It may be absent owing to congenital defects. Children born deaf are dumb 

 also. This is because we think with remembered sounds, and in a person born deaf 

 the auditory centres are never set into activity. By educating the child by the 

 visual inlet, it can be taught to think with the remembered shapes of the mouth 

 and expressions of the face produced in the act of speaking, and so can itself speak 

 in time. 



If a child becomes deaf before it is six or seven years old, there is a liability it 

 will forget the speech it has learnt, and so become dumb. 



In congenital hemiplegia there may be speechlessness, especially if the injury is 



