Treatise on human physiology : for the use of students and practitioners of medicine / by Henry C. Chapman.

  • Henry Cadwalader Chapman
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: Treatise on human physiology : for the use of students and practitioners of medicine / by Henry C. Chapman. Source: Wellcome Collection.

    841/942 page 853
    which particular octave or overtone is reinforced by the cavity of the mouth, the pitch of the latter depending upon its shape, and that the shape of the mouth remaining unchanged, the corresponding vowel _will be emitted as long as the expiration blast lasts. Now while the vowel i agrees with the four vowels just mentioned in being due to the reinforcement of an overtone, the fourth octave accompanying the fundamental by the cavity of the mouth, which in this instance is tuned to the pitch of the note Sib,, due to 3584 vibrations per second, an octave higher than in the case of the vowel e, it differs from the true vowels in that, the cavity of the mouth remaining the same, if the expiratory blast be prolonged, it does not remain i, but becomes e. The vowels are the only real vocal sounds, it being only on a vowel that a note can be said or sung. Speech, however, is made up not only of vowels, but of consonants—that is, of sounds that are sounded In conjunction with a vowel. While the distinction between vowels and consonants, as already mentioned, is not an absolute one, it may be said that while vowels are due to the vibrations of the vocal membranes being modified by the mouth, consonants are due to the expiratory blast being interrupted in various ways in its course through the throat and mouth; the vibrations of the vocal membranes, when essen- tial, being rather secondary in character. Consonants may be divided according to their manner of production, into two kinds, explosive and continuous, the sound of the explosive consonants being due to the sudden establishment or removal of a particular interruption, that of the continuous consonant to the air rushing continuously through some constriction, for example, explosive consonants are the labials p, b, dentals t, d, and gutturals k, g,p,t, and k, being uttered without the voice, b, d, and g (hard) with the voice—that is, are accompanied by a vowel sound. In uttering p, the lips are first closed, then the expiratory blast suddenly opening them, the sound is produced. —Simi- larly the sudden interruption of the contact of the tip of the tongue with the hard palate, and of the root of the tongue with the soft palate gives rise respectively to the sounds tand k. The continuous con- sonants are subdivided into aspirates, resonants, and vibratory. The aspirates include the labials f, v, the dentals s, 1, sh, th (hard), z, zh, th (soft), and the gutturals ch, gh. Like the explosive * consonants, some of the aspirates are uttered without the voice, as f, s, ], sh, c, h; some with the voice, as v, z, zh, th, ch. The reso- nants include the sounds m, n, ng, and the vibratory the sound r, common and guttural. Of the aspirates, f ands are formed through the lips and teeth being brought nearly in contact respectively ; th through the placing of the tongue between the two partially open rows of teeth; | when the tip of the tongue is placed against the hard palate, and the air escapes at the sides; sh through the dorsal surface of the tongue being raised toward the palati, the passage-way between the two being thereby narrowed; ch and gh through the approximation of the root of the tongue to the soft palate. In the production of all of the resonants the vocal membranes vibrate and the nasal chambers resonate, the closing of the lips in particular giving rise to m, the contact of the tongue with the hard palate to n, and the approximation of the root of
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