[Illustration: FIG. 49 (Spalteholz). Showing well the scroll (turbinated) bones of the nose, which break up the space and make it more cavernous. It can be seen that there is free communication behind, between the mouth and the nasal cavities, and that if the soft palate and the tongue approximate, the breath-stream must pass into and through the nose, giving rise to nasality in utterance.] A short description of a part to which many voice-users remain strangers all their lives will now be given. These resonance-chambers remain, for many, an apparatus used daily and absolutely essential, yet never examined. Fortunately, a few illustrations, which should be followed by an examination of the student's own resonance-chambers and their various parts as they may be seen in a mirror, will remove all difficulty in the understanding of them, and prepare for that detailed study to be recommended in a subsequent chapter. Passing from before backward, one meets the _lips_, the _teeth_ and _gums_, the _hard palate_, which is a continuation of the gums; then, suspended from the hard palate, behind, is the _soft palate_, back of which lies the _pharynx_ (often termed "the throat"), and above it and constituting its continuation, the _naso-pharynx_; and lying on the floor of the mouth there is the _tongue_. Certain of these parts, as the teeth, gums, hard palate, nasal bones, etc., constitute fixed structures, and though they determine in no small measure the shape of the resonance-chambers, and so to a degree the quality of the voice, so movable are the lips, soft palate, and, above all, the tongue, that there is the widest scope for varying the quality and even the volume of the voice; so that it is a good thing, practically, for every one to believe that so far as quality, at all events, is concerned, he is the master of his own destinies. Though we are accustomed to believe that the mouth and nose are, though neighbors, quite separate and independent of each other, such is not the case. Indeed, in the pre-natal condition these are not two, but one; and in some instances they remain imperfectly separated, owing to the failure of the hard palate to develop to the full--a condition known as "cleft palate," and giving rise to a peculiar nasal intonation, to be explained presently. The _nasal chambers_ are divided into two by a vertical partition, as one can readily demonstrate by the use of his fingers, and are still further broken up by certain bones, the scroll-shaped or _turbinated_ bones, so that the nasal chambers are of very limited size, and much divided up by bony outgrowths from their walls. The _vertical septum_, while bony above, is cartilaginous and flexible below.