SPEECH 307 



together by the sounds or noises to which the varying form of these 

 cavities gives rise. Here we come upon the fundamental distinction 

 between vowels and consonants. Vowels are musical sounds; con- 

 sonants are not musical sounds, but noises that is to say, they are 

 due to irregular vibrations, not to regularly recurring waves, the 

 frequency of which the ear can appreciate as a definite pitch. This 

 difference of character corresponds to a difference of origin: the 

 vowels are produced by the vibrations of the vocal cords ; the con- 

 sonants are due to the rushing of the expiratory blast through 

 certain constricted portions of the buccal chamber, where a kind of 

 temporary glottis is established by the approximation of its walls. 

 One of these * positions of articulation ' is the orifice of the lips; the 

 consonants formed there, such as p and b, are called labials. A 

 second articulation position is between the anterior part of the 

 tongue and the teeth and hard palate. Here are formed the dentals, 

 t, d, etc. The ordinary English r, and the r of the Berwickshire and 

 East Prussian ' burr/ also arise in this position through a vibratory 

 motion of the point of the tongue. The third position of articula- 

 tion is the narrow strait formed between the posterior portion of the 

 arched tongue and the soft palate. To the consonants arising here 

 the name of gutturals has been given. They include k, g, the 

 Scottish ch, and the uvular German r. The latter is produced by 

 a vibration of the uvula. The aspirated h is a noise set up by the 

 air rushing through a moderately wide glottis, and some have there- 

 fore included the glottis as a fourth articulation position for con- 

 sonants. Certain sounds like n, m, and ng, when final (as in pen, 

 dam, ring), although produced at the glottis, are intensified by the 

 resonance of the air in the nose and pharynx, and are sometimes 

 spoken of as nasal consonants. 



As we have said, the vowels are produced by vibrations of the 

 vocal cords, but to what they owe their special timbre or quality has 

 been much discussed. According to the view with which Helm- 

 holtz's name is particularly connected this is due to the reinforce- 

 ment of certain overtones by the resonating cavities, the shape and 

 fundamental tone of which are different for each vowel. 



When a vowel is whispered, the mouth assumes a characteristic 

 shape, and emits the fundamental tone proper to the form and size 

 of the particular ' vowel-cavity/ not as a reinforcement of a tone set 

 up by the vibrations of the vocal cords, but in response to the rush of 

 air through the cavity; just as a bottle of given shape and size gives out 

 a definite note when the air which it contains is set in vibration, by 

 blowing across its mouth. A whisper, in fact, is speech without voice; 

 the larynx takes scarcely any part in the production of the sound ; the 

 vocal cords remain apart and comparatively slack; and the expiratory 

 blast rushes through without setting them in vibration. 



The fundamental tone of the ' vowel-cavity ' may be found for each 

 vowel by placing the mouth in the position necessary for uttering it, 

 then bringing tuning-forks of different period in front of it, and noting 



