larynx is wide open, and the vibrating air rushes forth in a full, broad stream of sound.
Many singing-masters, not content with the great natural divisions of the voice which have just been indicated, insist that there are five different registers, each with a distinct mechanism of its own. I am not a maestro, and therefore I am willing to admit that, artistically speaking, there ought to be five registers, or, in fact, any number of them that may be thought desirable. But if that is a necessity of art, it is not a necessity of Nature, which does all that is required by the simple process which has been described. The differences of mechanism on which the singingmasters profess to base their division are mostly of so subtle a nature as to be almost invisible to the eye, and sometimes even hardly appreciable by the ordinary intellect. I think, however, there is a way of reconciling their views with mine, diametrically opposed as they at first sight seem to be. As a physiologist, I speak solely of the tone of a note, that is to say, of its place in the musical scale, and I say, That note is delivered by the long reed or short reed adjustment, as the case may be; as musicians, on the other hand, the maestri, speaking of the quality as well as the tone, say, That note ought to be delivered in such and such a way to make it artistically beautiful. In the one case, in short, the voice is considered purely as it is produced in the larynx; in the other, as it is delivered by a well-trained singer managing his resonance apparatus to the best advantage. Now, for this result many things are needed besides the correct adjustment of the vocal cords. The supply of breath must be regulated to a nicety, and the position of the tongue, soft palate, cheeks, and lips must be precisely that which is best for the utterance of each particular note. There are rules founded on experience which govern all these things; these rules are expressed in terms of subjective sensations, which are scientifically absurd, but, at the same time, may be practically useful, as indicating the feelings that should accompany the right performance of the manœuvre required. It is on all this complicated mechanism that the five registers of the singing-masters are based; the more or less fanciful changes in the larynx, to which they attribute the slight, but artistically vital, differences in production which their trained ear enables them to appreciate, have in reality but little share in the result. The difference between artistic and inartistic production of the voice depends far more on the management of the resonators than on the adjustment of the vocal cords.
This point will be better understood if it is borne in mind that, as Helmholtz has shown, every musical sound is "compounded of many simples"; that is to say, the fundamental tone is re-enforced by a number of secondary sounds or "harmonics" which accom-
