Some consonants are formed without either in- or out-breathing, but solely with the air in the throat or mouth. In forming “suction stops” or “clicks” the tongue or lips are put in the position for a stop, and the air is sucked out from between the organs in contact, so that when the stop is loosened, a smacking sound is produced by the air rushing in to fill the vacuum. Thus the point-click is the interjection of impatience commonly written tut! In many savage languages clicks are a part of ordinary speech.
Synthesis.—Besides analysing each sound separately, phonetics has to deal with the phenomena which accompany synthesis or the combination of sounds. Although a sentence may consist of a single word, and that word of a single vowel, sounds mostly occur only in combination with one another. The ordinary division into sentences and words is logical, not phonetic: we cannot mark off sentences and cut them up into words until we know what they mean and are able to analyse them grammatically. But the logical division into sentences corresponds to some extent with the phonetic division into “breath-groups,” marked off by our inability to utter more than a certain number of syllables in succession without pausing to take breath. Within each of these breath-groups there is no necessary pause between the words, except when we pause for emphasis. The only necessary phonetic divisions within the breath-group are those into syllables, sounds and intervening “glides.” But before considering these last it will be necessary to say something about the general factors of synthesis: quantity, stress and intonation.
As regards quantity, it is enough for ordinary purposes to distinguish three degrees long, half-long or medium and short. In English what are called long vowels keep their full length when stressed and before final voice consonants, as in see, broad; and become half-long before voiceless consonants, as in cease, brought. In most other languages full length is preserved alike before all classes of consonants. The Romance lan uages have short final stressed vowels, as in French si. Unstressed vowels tend to become short in most languages. The distinctions of quantity apply to consonants as well as vowels. Thus English tends to lengthen final consonants after short stressed vowels, as in man compared with German mann, where the final consonant is quite short. Consonants, like vowels, tend to become short when unstressed. But in some languages, such as Finnish and Hungarian, stress has no effect on quantity, so that in these languages long vowels and double consonants occur as frequently in unstressed as in stressed syllables. Even in English we often lengthen final unstressed vowels in exclamations, as in what a pity! Some languages, such as the Romance languages and Russian, tend to level the distinctions of vowel quantity. most of their vowels are half-long.
Stress is, organically the result of the force with which the breath is expelled from the lungs; while acoustically it produces the effect of loudness, which is dependent on the size of the sound vibrations: the bigger the waves, the louder the sound, and the greater the stress, of which we may distinguish infinite degrees. If we distinguish only three, they are called weak, medium and strong. The use of stress in different languages shows the same variety as quantity. Some languages, such as French, make comparatively little use of its distinctions, uttering all the syllables of words and sentences with a more or less even degree of force. English, on the other hand, makes great use of minute distinctions of stress both to distinguish the meanings of words and to mark their relations in sentences.
With stress is closely connected the question of syllable-division. A syllable is a group of sounds containing a “syllabic” or syllable-former, which is, of course, able to constitute a syllable by itself. The distinction between syllabic and non-syllabic depends on sonority, the more sonorous sounds being the voiced ones, while of these again, the most open are the most sonorous, the most sonorous of all being the vowels, among which, again, the openest are the most sonorous. But these differences are only relative. When a vowel and a consonant come together the sonorousness of the vowel always overpowers that of the consonant, so that the two together only constitute one syllable. But in such a word as little the second (l) is so much more sonorous than the accompanying voiceless stop that it assumes syllabic function, and the whole group becomes dissyllabic to the ear. The beginning of a syllable corresponds with the beginning of the stress-impulse with which it is uttered. Thus in atone the strong stress and the second syllable be in on the (t), and in bookcase on the second (k), the first (k) belonging to the first syllable, so that the (kk) is here double, not merely long, as in book (bukk) by itself.
Intonation or variation of tone (pitch) depends on the rapidity of the sound-vibrations the more rapid the vibrations, the higher the pitch. Intonation is heard only in voiced sounds, as being the only ones capable of variations of pitch.
In singing the voice generally dwells on each note without change of pitch, and then leaps up or down to the next note as quickly as possible, so that the intervening “glide” is not noticed—except in what is called portamento. In speaking, on the other hand, the voice hardly ever dwells on any one note, but is constantly gliding upwards or downwards, so that an absolutely level tone hardly ever occurs in speech. But in the rising and falling inflections of speech we can distinguish between “voice-glides” (portamentos or slurs) and “voice-leaps,” although the distinction is not so definite as in singing.
Of the three primary forms of intonation the level tone ( ) can be approximately heard in well as an expression of musing—although it really ends with a slight rise, the rising (´) in the question well?; the falling (`) in the answer yes. There are besides compound tones formed by uniting the two last in one syllable. The compound rising tone (ˇ) may be heard in take care! the compound falling tone (ˆ) in the sarcastic oh! All these tones may be varied according to the intervals through which they pass. The greater the interval, the more emphatic the tone. Thus a high rise, which begins high, and consequently can only rise a little higher, expresses simple question, while the same word, if uttered with a low rise extending over an interval of between a fifth and an octave—or even more—expresses various degrees of surprise or indignation, as in the emphatic what! compared with the simply interrogative what?
In English and most European languages, intonation serves to modify the general meaning and character of sentences. This is sentence-intonation. But some languages, such as Swedish and Norwegian, and Chinese, have word-intonation, by which words which would otherwise be identical in sound are distinguished. The distinction between Gr. oíkoi and oîkoi was no doubt one of intonation.
Glides.—Such a word as cat consists not only of the vowel and the two consonants of which it is made up, but also of “glides” or transitions between these sounds. The glide from the initial consonant to the vowel consists of all the intermediate positions through which the tongue passes on its way from the (k)-position to the (ae)-position. The number of these positions is infinite, but they are all implied by the mere juxtaposition of the symbols, for it is assumed that in all transitions from one position to another the shortest way is taken. Although the direction of a glide is dependent on the positions of the two fixed points between which it lies, its character may be varied both by the shape of the configurative passages—especially the glottis—and by stress and quantity.
In the word given above the “off-glides” from the consonants are both breath-glides, the glottis being kept open during the transition from the voiceless consonant to the following vowel, or, as in the case of the final consonant, to silence. The “on-glide” from the vowel to the (t) is, on the other hand, a voice glide, the closure of the glottis being maintained till the stop is made.
In French and most of the languages of the south of Europe voiceless consonants are followed by voice-glides. Thus in French qui there is no escape of breath after the (k), as there is in English Key. Other languages again have breath on-glides before voiceless stops.
If an independent strong stress is put on the breath-glide of English key, it is heard almost as a full independent consonant, and becomes an “aspirate.” Aspirated steps may be heard in the Irish-English pronunciation of such words as tell, and also in Danish, and in Sanskrit as pronounced in India. If the voice-glide after a voice stop is emphasized in a similar way the “sonant aspirates” of Sanskrit and its modern descendants are produced, as in Sanskrit dhanu.
Glides are especially important from an acoustic point of view. Acoustically speaking, indeed, voiceless stops are pure glide sounds, the stop itself being inaudible. In voice-stops, on the other hand, the stop itself can be made audible as well as the intervening glides. In English these latter are fully voiced when they come between voice sounds, as in ago; but when preceded by voiceless sounds or by a pause, as in go! they are formed with imperfect vocality, full voice being heard only just before the stop is loosened. So also initial English (z) as in zeal is formed with imperfect vocality under the same conditions, so that it sounds like (sz). In French and other languages which have voice-glides after voiceless consonants initial (g, z) &c. are fully voiced.
Consonant-glides may be further modified in various ways. In the formation of “implosive” stops, such as occur in Saxon German, Armenian and other languages, voiceless stops followed
