MECHANISM OF SPEECH. 501 



long before these laws were ascertained and defined, as has lately been done, 

 particularly by Helmholtz. 



MECHAKISM OF SPEECH. 



Articulate language consists in a conventional series of sounds made for 

 the purpose of conveying certain ideas. There being no universal language, it 

 will be necessary to confine the description of speech to the language in which 

 this work is written. Language, as it is naturally acquired, is purely imitative 

 and does not involve of necessity the construction of an alphabet, with its 

 combinations into syllables, words and sentences ; but as civilization has ad- 

 vanced, certain differences in the accuracy and elegance with which ideas are 

 expressed have become associated with the degree of development and culti- 

 vation of the intellectual faculties. Philologists have long since established 

 a certain standard varying, to some extent, it is true, with usage and the ad- 

 vance of knowledge, but still sufficiently definite by which the correctness 

 of modes of expression is measured. It is not proposed to discuss the science 

 of language, or to consider, in this connection at least, the peculiar mental 

 operations concerned in the expression of ideas, but to take the language as 

 it exists, and to describe briefly the mechanism of the production of the 

 most important articulate sounds. 



Almost every language is imperfect, as far as an exact correspondence be- 

 tween its sounds and written characters is concerned. The English language 

 is full of incongruities in spelling, such as silent letters and arbitrary and 

 unmeaning variations in pronunciation ; but these do not belong to the sub- 

 ject of physiology. There are, however, certain natural divisions of the sounds 

 as expressed by the letters of the alphabet. 



Vowels. Certain articulate sounds are called vowel, or vocal, from the 

 fact that they are produced by the vocal chords and are but slightly modified 

 as they pass out of the mouth. The true vowels, , e, i, 0, , can all be sounded 

 alone and may be prolonged in expiration. These are the sounds chiefly em- 

 ployed in singing. The differences in their characters are produced by changes 

 in the position of the tongue, mouth and lips. The vowel-sounds are neces- 

 sary to the formation of a syllable, and although they generally are modified 

 in speech by consonants, each one may of itself form a syllable or a word. 

 In the construction of syllables and words, the vowels have many different 

 qualities, the chief differences being as they are made long or short. In addi- 

 tion to the modifications in the vowel-sounds by consonants, two or three 

 may be combined so as to be pronounced by a single vocal effort, when they 

 are called respectively, diphthongs and triphthongs. In the proper diph- 

 thongs, as 0?, in voice, the two vowels are sounded. In the improper diph- 

 thongs, as ea, in heat, and in the Latin diphthongs, as ce, in Caesar, one of 

 the vowels is silent. In triphthongs, as eau, in beauty, only one vowel is 

 sounded. F, at the beginning of words, is usually pronounced as a conso- 

 nant ; but in other positions it is pronounced as e or i. 



An important question relates to the differences in the quality of the dif- 

 ferent vowel-sounds when pronounced with equal pitch and intensity. The 



