Grief unburdening itself uses tones approaching in timbre to those of chanting:  and in his most pathetic passages an eloquent speaker similarly falls into tones more vibratory than those common to him.  Now any one may readily convince himself that resonant vocal sounds can be produced only by a certain muscular effort additional to that ordinarily needed.  If after uttering a word in his speaking voice, the reader, without changing the pitch or the loudness, will sing this word, he will perceive that before he can sing it, he has to alter the adjustment of the vocal organs; to do which a certain force must be used; and by putting his fingers on that external prominence marking the top of the larynx, he will have further evidence that to produce a sonorous tone the organs must be drawn out of their usual position.  Thus, then, the fact that the tones of excited feeling are more vibratory than those of common conversation is another instance of the connection between mental excitement and muscular excitement.  The speaking voice, the recitative voice, and the singing voice, severally exemplify one general principle.

That the pitch of the voice varies according to the action of the vocal muscles scarcely needs saying.  All know that the middle notes, in which they converse, are made without any appreciable effort; and all know that to make either very high or very low notes requires a considerable effort.  In either ascending or descending from the pitch of ordinary speech, we are conscious of an increasing muscular strain, which, at both extremes of the register, becomes positively painful.  Hence it follows from our general principle, that while indifference or calmness will use the medium tones, the tones used during excitement will be either above or below them; and will rise higher and higher, or fall lower and lower, as the feelings grow stronger.  This physiological deduction we also find to be in harmony with familiar facts.  The habitual sufferer utters his complaints in a voice raised considerably above the natural key; and agonising pain vents itself in either shrieks or groans—­in very high or very low notes.  Beginning at his talking pitch, the cry of the disappointed urchin grows more shrill as it grows louder.  The “Oh!” of astonishment or delight, begins several notes below the middle voice, and descends still lower.  Anger expresses itself in high tones, or else in “curses not loud but deep.”  Deep tones, too, are always used in uttering strong reproaches.  Such an exclamation as “Beware!” if made dramatically—­that is, if made with a show of feeling—­must be many notes lower than ordinary.  Further, we have groans of disapprobation, groans of horror, groans of remorse.  And extreme joy and fear are alike accompanied by shrill outcries.