3.—THEORY OF THE VOICE.
Provide a species of whistle common as a child’s toy, or a sportsman’s call, in the form of a hollow cylinder, about three fourths of an inch in diameter, closed at both ends by flat circular plates with holes in their centres. Hold this toy between the teeth and the lips; blow through it, and you can produce sounds, varying in pitch with the force with which you blow. If the air be cautiously graduated, all the sounds within the compass of a double octave may be produced from it, and if great precaution be taken in the management of the breath even deeper tones may be brought out. This simple instrument or toy, has indeed the greatest resemblance to the larynx, which is the organ of the voice.