Institutio Oratoria

But here again there are many intermediate gradations between the two extremes, and just as the face, although it consists of a limited number of features, yet possesses infinite variety of expression, so it is with the voice: for though it possesses but few varieties to which we can give a name, yet every human being possesses a distinctive voice of his own, which is as easily distinguished by the ear as are facial characteristics by the eye.

The good qualities of the voice, like everything else, are improved by training and impaired by neglect. But the training required by the orator is not the same as that which is practised by the singing-master, although the two methods have many points in common. In both cases physical robustness is essential to save the voice from dwindling to the feeble shrillness that characterises the voices of eunuchs, women and invalids, and the means for creating such robustness are to be found in walking, rubbing-down with oil, abstinence from sexual intercourse, an easy digestion, and, in a word, in the simple life.

Further, the throat must be sound, that is to say, soft and smooth; for if the throat be unsound, the voice is broken or dulled or becomes harsh or squeaky. For just as the sound produced in the pipe by the same volume of breath varies according as the stops are closed or open, or the instrument is clogged or cracked, so the voice is strangled if the throat be swollen, and muffled if it

Again, the presence of some obstacle may divide the breath just as a pebble will divide shallow waters, which, although their currents unite again soon after the obstruction is past, still leave a hollow space in rear of the object struck. An excess of moisture also impedes the voice, while a deficiency weakens it. As regards fatigue, its effect is the same as upon the body: it affects the voice not merely at the moment of speaking, but for some time afterwards.