The laryngoscope should not, in fact, leave the hands of the physician. Invaluable for the detection of diseases of the throat which impair the voice and which have to be cured either by treatment or operation before the voice can be restored to its original potency or charm, its value in studying the physiology of voice-production and the functions of the vocal organs is doubtful. In fact, it is its use by amateur laryngoscopists that has resulted in the promulgation of all kinds of absurd theories of voice-study and in those innumerable pet methods of vocal instruction, each one of which may safely be guaranteed to destroy expeditiously whatever of voice originally existed. Fascinating as it may seem to the singer to examine his own larynx while he is producing a vocal tone—"during phonation," the physiologist would say—the value of the deductions formed from such observation may be doubted, if for no other reason than that the introduction of the mirror into the back of the mouth makes the whole act of phonation strained
and the effects observed unnatural. In fact, as Mackenzie already has pointed out, although the laryngoscope is invaluable in the recognition and treatment of diseases which before only could be guessed at, "with the exception of certain points relating to the 'falsetto' register, it can scarcely be said to have thrown any new light on the mechanism of the voice." In other words, the instrument belongs in the hands of the physician, not in those of the singer.
The larynx, as I already have stated, is a small organ, on an average two inches long and one and a half inch wide. The reader can form a good idea of its location by the Adam's apple, which is its most forward projection at the top.
From the singer's point of view the larynx exists for the sake of the vocal cords—in order that they may be acted upon by certain muscles and thus relaxed or tightened, lengthened or shortened, or by a combination of these states properly adjusted to the note that is to be produced. The vocal cords lie parallel to each other. The space between them (the opening through which the air from the windpipe passes up into the larynx) is called the glottis. With every loosening, tightening, lengthening or shortening of the vocal cords or
other effect of muscular action upon them, the space between them—the glottis—alters in size and shape. These subtle changes in the size and shape of the glottis are, as I shall expect to show, of great importance in voice-production. They form the first step in the actual creation of voice.
The numerous and subtle adjustments and readjustments in shape of which the larynx is capable could not be effected if its shell consisted of so hard and unyielding a substance as bone. Consequently, it has to consist of a substance which, while sufficiently solid to form a background for the attachment of its numerous muscles, yet is sufficiently pliable to yield with a certain degree of elasticity to the action of these. Nature therefore has built up the larynx with cartilage, or gristle, providing a framework made up of a series of cartilages, sufficiently joined to form a firm shell surrounding the muscular tissue, yet, being hinged as well as joined, capable of independent as well as of combined movement, and, withal, possessing the requisite degree of pliability to respond in whole or part to the extremely varied and often delicate action of the laryngeal muscles—muscles which indeed are required to be as practised and as sensitive to suggestion as if they were nerves.
The principal cartilage of the larynx is the thyroid or shield cartilage, named from the Greek thureos (shield). It really consists of two shields joined along the edges in front (its most forward upper projection being the Adam's apple) and opening out at the back. The thyroid is the uppermost cartilage of the larynx and the Adam's apple is the uppermost portion of the front of the larynx. But as the shields open out back of the Adam's apple, they slope upward and at the extreme back each shield has a marked upward prolongation like a horn. By these horns, enforced by membrane, the thyroid cartilage and through it the whole larynx is attached to and is suspended from the hyoid bone, or tongue-bone. This gives mobility to the larynx and freedom of movement to the neck; and the larynx, while mobile as a whole, furthermore is capable of an infinite number of muscular adjustments and readjustments within itself.
At the back the lower edges of the thyroid rest upon the cricoid cartilage, which derives its name from the Greek krikos, a signet-ring. This is next in size to the thyroid. The broader portion, the part which corresponds to the seal in a signet-ring, is at the back. Attached at the back, the