Consonants and Vowels.
If we regard the vowels as a continuous stream of air, emitted as breath from the lungs and changed into sound as it leaves the larynx, we may look upon the consonants as a number of stops opposing for a moment the free passage of this vocal stream after it has left the larynx and before it reaches the open air. These consonantal stops, against which the waves of the vowels break themselves more or less distinctly, are produced by barriers formed by the contact between the tongue, throat, palate, teeth, and lips.
Consonants.
Gutturals, Dentals, and Labials.
According to an observation which we find already in Vaidik grammars, the principal consonantal sounds in any language are:—
the guttural (k),
the dental (t),
the labial (p).
The pure guttural sound, without any regard as yet to its modifications (whether tenuis, media, aspirata, nasalis, semi-vocalis, or sibilans), is produced by stopping the stream of sound by means of a contact between the root of the tongue and the throat. The throat is called the "place," the root of the tongue the "instrument," of the guttural.
The pure dental sound is produced by contact between tongue and teeth. Here the teeth are called the "place," and the tip of the tongue the "instrument."
The pure labial sound is produced by contact between the upper and lower lip; the upper lip being the "place," the lower the "instrument."
All consonants, excluding semi-vowels and sibilants, are formed by a complete contact between "place" and "instrument."
Formation of the Tenuis.
If the vocal breathing is stopped sharp by the contact of the organs, so as to allow for the moment no consonantal sound or tone to escape, the consonant is called tenuis (ψιλόν), hard or surd (k, t, p).
