In addition to what has been said, it is of great importance to attend particularly to tones and gestures. To almost every sentiment we utter, more especially, to every strong emotion, nature has adapted some peculiar tone of voice. And we may observe, that every man, when he is much in earnest in common discourse, when he is speaking on some subject which interests him nearly, has an eloquent or persuasive tone and manner.
If one were to tell another that he was very angry, or very much grieved, in a tone which did not suit such emotions, instead of being believed, he would be laughed at. The best direction which can be given, is, to copy the proper tones for expressing every sentiment from those which nature dictates to us in conversation with others.
With respect to gesture, the few following hints may be of some service. When speaking in public, one should endeavor to preserve as much dignity as possible in the whole attitude of the body. An erect posture is generally to be chosen; standing firm so as to have the fullest command of all his motions. Any inclination, which is used, should be forwards towards the hearers, which is a natural expression of earnestness.
As for the countenance, the chief rule is, that it should correspond with the nature of the discourse; and when no particular emotion is expressed, a serious and manly look is always the best. The eyes should never be fixed close on any one object, but more easily round upon the whole audience.
In the motions made with the hands consists the chief part of gesture in speaking. The right hand should be used more frequently than the left. Warm emotions demand the motion of both hands corresponding together. All the gestures should be free and easy. Perpendicular movements with the hands, that is, in a straight line up and down are seldom good. Oblique motions are, in general, the most graceful.
Motions made with the hands should proceed rather from the shoulders than from the elbows; for they appear much more easy. Too sudden and nimble motions should be avoided. Earnestness can be fully expressed without them. Above all things, a speaker should guard against affectation, which is always disgustful.