The mind often manifests, through the cranial nerves, states of mind of which the person is unconscious. While consciousness is the power by which one knows his own states of mind, there is no proof that consciousness takes note of all one’s states of mind. The proof that it does not is found in the fact that people, through involuntary acts, often manifest mental activities of which they are unconscious. Spontaneous expression is truest. The facial nerve causes the muscles of the face to portray the thoughts and feelings of the soul more truthfully than any artist could delineate them with pencil and brush. Before we can properly teach vocal culture and oratorical expression we must understand the principle of spontaneous manifestation by means of cranial nerves as distinct from purposeful forms of expression. The facial nerve not only acts as a motor of expression through the face, causing it to reveal thought and emotion, but acts in the same manner upon the tongue, causing it to form and modulate tones in song and speech. Again note the nature of the hypo-glossal cranial nerve, which is not only a motor of the tongue, causing it to act spontaneously, but is distributed also to the muscles of the neck which are concerned in the movements of the larynx. The purpose of this distribution is probably to associate the action of the tongue with that of the larynx which is necessary for articulate speech. All the motions of the tongue are performed through the medium of these nerves.