Observations on the Human Voice Author(s): Manuel Garcia Source: Proceedings of the Royal Society of London, Vol. 7 (1854 - 1855), pp. 399-410 Published by: Royal Society Stable URL: https://www.jstor.org/stable/111815 Accessed: 23-02-2020 08:49 UTC JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at https://about.jstor.org/terms Royal Society is collaborating with JSTOR to digitize, preserve and extend access to Proceedings of the Royal Society of London This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 399 ing. I have little doubt but the Varna and Balaklava wire will be the best yet made for the purpose. Without knowing exactly what the " retardation " may be in terms of the element of time "' ai" of the diagrams, we may judge what the retardation, if similarly estimated, would be found to be in other cables of stated dimensions. Thus, if the retardation in 200 miles of submarine wire between Greenwich and Brussels be -1-th of a second, the retardation in a cable of equal and similar transverse section, extending half round the world (14,000 miles), would be 14000 ) -XY=490 seconds, or 8- minutes: and in the telegraphic cable (400 miles) between Varna and Balaklava, of which the electro-statical capacity per unit of length may be about one-lhalf greater than in the other, while the conducting power of the wire is probably the same, the retardation may be expected to be ? X2x lO-= - of a second. The rate at which distinct signals could be propagated to the remote end would perhaps be one signal in about a quarter of an hour in the former case, and nearly two signals in a second in the latter. IV. " Observations on the Human Voice." By MANUEL GARCIA, Esq. Communicated by Dr. SHARPEY, Sec. 1R.S. Received March 22, 1855. The pages which follow are intended to describe some observations made on the interior of the larynx during the act of singing. The method which I have adopted is very simple. It consists in placing a little mirror, fixed on a long handle suitably bent, in the throat of the person experimented on against the soft palate and uvula. The party ought to turn himself towards the sun, so that the luminous rays falling on the little mirror, may be reflected on the larynx. If the observer experiment on himself, he ought, by means of a second mirror, to receive the rays of the sun, and direct them on the mirror, which is placed against the uvula. We shall This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 400 now add our own deductions from the observations which the image reflected by the mirror has afforded us. Opening of the Glottis. At the moment when the person draws a deep breath, the epiglottis being raised, we are able to see the following series of movements :-the arytenoid cartilages become separated by a very free lateral movement; the superior ligaments are placed against the ventricles; the inferior ligaments are also drawn back, though in a less degree, into the same cavities; and the glottis, large and wide open, is exhibited so as to show in part the rings of the trachea. But unfortunately, however dexterous we may be in disposing these organs, and even when we are most successful, at least the third part of the anterior of the glottis remains concealed by the epi- glottis. Movement of the Glottis. As soon as we prepare to produce a sound, the arytenoid cartilages approach each other, and press together by their interior surfaces, and by the anterior apophyses, without leaving ainy space, or intercartilaginous glottis; sometimes even they come in contact so closely as to cross each other by the tubercles of Santorini. To this movement of the anterior apophyses, that of the ligaments of the glottis corresponds, which detach themselves from the ventricles, come in contact with different degrees of energy, and show themselves at the bottom of the larynx under the form of an ellipse of a yellowish colour. The superior ligaments, together with the arvteno-epiglottidean folds, assist to form the tube which surmounts the glottis; and being the lower and free extremity of that tube, enframe the ellipse, the surface of which they enlarge or diminish according as they enter more or less into the ventricles. These last scarcely retain a trace of their opening. By anticipation, we might say of these cavities, that, as will afterwards appear clearly enough in these pages, they only afford to the two pair of ligaments a space in which they may easily range themselves. When the arytenio-epiglottidean folds contract, they lower the epiglottis, and make the superior orifice of the larynx considerably narrower. The meeting of the lips of the glottis, naturally proceeding from the front towards the back, if this movement is well managed, it This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 401 will allow, between the apophyses, of the formation of a triangular space, or inter-cartilaginous glottis, but one which, however, is closed as soon as the sounds are produced. After some essays, we perceive that this internal disposition of the larynx is only visible when the epiglottis remains raised. But neither all the registers of the voice, nor all the degrees of intensity, are equally fitted for its taking this position. We soon discover that the brilliant and powerful sounds of the chest-register contract the cavity of the larynx, and close still more its orifice; and, on the contrary, that veiled notes, and notes of moderate power, open both so as to render any observation easy. I'he falsetto register especially possesses this prerogative, as well as the first notes of the headvoice*. So as to render these facts more precise, we will study in the voice of the tenor the ascending progression of the chestregister, and in the soprano that of the falsetto and head-registers. Emission of the Chest-voice. If we emit veiled and feeble, sounds, the larynx opens at the notes do, re, mi,t 2 2 2 and we see the glottis agitated by large and out its entire extent. Its lips comprehend rior apophyses of the arytenoid cartilages I repeat it, there remains no triangular space. As the sounds ascend, the apophyses, which are slightly rounded on their internal side, by a gradual apposition commencing at the back, encroach on the length of the glottis; and as soon as we * Let us here observe, that three registers of voice are generally admitted,chest, falsetto, and head. The first begins lower in a man's voice than in a woman's; the second extends equally in both voices; the third reaches higher in the female voice. Table of the Human Voice in its full extent. v~~~~~~~~~~~:. 4Chest -- LA_ I__ ad------ - _ . -- - Falsetto / t The musical limits we establish in the course of these pages vary a little in each individual. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 402 reach the sounds si, do, , they finish by touching each other throughout their whole extent; but their summits are only solidly fixed one against the other at the notes do#, r6, = In some organs these summits are a little vacillating when they form the posterior end of the glottis, and the two or three half tones which are formed show a certain want of purity and strength, which is very well known to singers. From the dot, re, ____ the 3 3 vibrations, having become rounder and purer, are accomplished by the vocal ligaments alone, up to the end of the register. The glottis at this moment presents the aspect of a line slightly swelled towards its middle, the length of which diminishes still more as the voice ascends. We also see that the cavity of the larynx has become very small, and that the superior ligaments have contracted the extent of the ellipse to less than one-half. When instead of veiled and feeble sounds, we make use of full and vibrating ones, the glottis becomes visible only at the sounds mi, fa, _ , and those above them, a limit which depends 3 3 3-____ to a certain extent on the dexterity of the singer. For all the rest, the organs act as we have just said, but with a double difference: 1. The cavity of the larynx contracts itself more when the voice is intense, than wlhen it is feeble. 2. The superior ligaments are contracted so as to reduce the small diameter of the ellipse to a width of two or three lines. But however powerful these contractions may be, neither the cartilages of Wrisberg, nor the superior ligaments themselves, ever close sufficiently to prevent the passage of the air, or even to render it difficult. This fact, which is verified also with regard to the falsetto and hlead-registers, suffices to prove that the superior ligaments do not fill a generative part in the formation of the voice. We may draw the same conclusion by considering the position occupied by the somewhat feeble muscles which correspond to these ligaments; they cover externally the extremity of the diverging fibres of the thyro-arytenoid muscles, and take part especially in the contractions of the cavity of the larynx during the formation of the high notes of the chest- and of the head- registers. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 403 Production of the Falsetto. The low notes of the falsetto, _ sol, lab, lab, -Ift-ea- 2 2 2 show the glottis infinitely better than the unisons of the chest-voice and produce vibrations more extended and more distinct. Its vibrating sides, formed by the anterior apophyses of the arytenoid cartilages, and by the ligaments, become gradually shorter as the voice ascends; at the notes la, si, g= 9 , the apophyses take 3 3 --- part only at their summits; and in these notes there results a weakness similar to that which we have remarked in the chest-notes an octave below. At the notes dot, re, * iE==, the ligaments 4 4 alone continue to act; then begins the series of notes called headvoice. The moment in which the action of the apophyses ceases, exhibits in the female voice a very sensible difference at once to the ear and in the organ itself. Lastly, we verify, that, up to the highest sounds of the register, the glottis continues to diminish in length and in width. If we compare the two registers in these movements, we shall find some analogies in them: the sides of the glottis, formed at first by the apophyses and the ligaments, become shorter by degrees, and end by consisting only of the ligaments. The chest-register is divided into two parts, corresponding to these two states of the glottis. The register of falsetto-head presents a complete similarity, and in a still more striking manner. On other points, on the contrary, these same registers are very unlike. The length of the glottis necessary to form a falsetto note, always exceeds that which produces the unison of the chest. The movements which agitate the sides of the glottis are also augmented, and keep the vibrating orifice continually half opened, which naturally produces a great waste of air. A last trait of difference, is in the increased extent of that elliptic surface. All these circumstances, which we shall refer to again, show in the mechanism of the falsetto, a state of relaxation, which we do not find in the same degree in the chest-register. Manner in which the sounds are formed. As we have just said, and what we have seen proves it, the in. VOL. X II. 2 Q This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 404 ferior ligaments, at the bottom of the larynx, form exclusively the voice, whatever may be its register or its intensity; for they alone vibrate at the bottom of the larynx *. But by virtue of what principle is the voice formed ? It seems to me, that the answer to this question can be but this; the voice is formed in one unique manner,by the compressions and expansions of the air, or the successive and regular explosions which it produces in passing through the glottis. The ligaments of the glottis are situate about the mean level of the upper border of the cricoid, close the passage, and present a resistance to the air. As soon as the air has accumulated sufficiently, it parts these folds and produces an explosion. But at the same instant, by virtue of tneir elasticity, and the pressure from below being relieved, they meet again to give rise to a fresh explosion. A series of these compressions and expansions, or of explosions, occasioned by the expansive force of the air and the reaction of the glottis, produces the voice. This thecry, though now generally admitted for reeds, and undoubtedly evident in the liquid vein, the toothed-wheel of Savart, the syre'ne of the Baron Cagnard Latour &c., has not to my knowledge, been yet applied to the glottist. If we consider. that the lips of this aperture, taken separately, can give no kind of sound, however we may try to make them speak, we must admit that the sounds which they give forth by their mutual action, are only owing to the explosions of the air produced by their strokes +. It is not necessary in order to obtain the explosion of sound, that the glottis should be perfectly closed each time after its opening; it suffices that it should oppose an obstacle to the air capable of developing its elasticity. In this case the rushing of the air is heard accompanying * We gladly acknowledge that this most important fact has been already announced by J. Muller, although we have our objections to the theory which accompanies it.-Handbuch der Physiologie des Menschen. t I find that Dr. Miller hints at the possibility of the voice being thus formed, but only to attack and reject the notion.-Ibidem. + Many controversies have arisen respecting the sounds sometimes emitted by animals after the section of the superior and recurrent laryngeal nerves; sounds which have been perhaps occasioned by the struggling of the animal causing a swelling of the neck and a mechanical contact of the vocal ligaments. However, without doubt, after the sectioni of these nerves, voice, as a voluntary act, can no longer take place. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 405 the sounds, and they take a veiled, and sometimes an extremely muffled character; an observation which we have already presented to the reader's notice in speaking of the falsetto. Conjectures on the Formation of the dijerent Registers. As the entire system of vibrations arises solely from the inferior ligaments, it is evident that the cause of the different tones called registers, must be sought for in the muscles which set these ligaments in motion; and that the other parts of the larynx must be considered only as apparatus for strengthenirng the sounds obtained, and for modifying their quality. In our efforts to discover the more intimate processes of the vocal organs which produce the sounds, we shall recur at once to the observations already mentioned, to some anatomical remarks which we are going to make, and to the sensations which we feel in the organ itself whilst it is producing sounds. If we detach one of the halves of the thyroid cartilage, we shall see a large muscular surface of oblique fibres, which fills all the space between the arytenoid and thyroid cartilages. At its upper end is to be seen the muscle corresponding to the superior vocal ligaments, and which sometimes extends to the notch in the thyroid. After detaching this generally frail muscle, all the fibres constituting this muscular surface seem to start from two opposite centres, viz. the anterior surface of the arytenoid, and the re-entering angle of the thyroid. These centres, occupying the extremities of a diagonal line, send their fibres towards each other in parallel lines. Those which start from the anterior face of the arytenoid descend obliquely; the most external ones go to the cricoid, whose posterior half they cover at the side; the most internal ones descend to the vocal membrane*, which they cover entirely. The fibres which terminate at the membrane become longer, as they become more internal. Those which start from the re-entering angle of the thyroid, reascend obliquely to the summit of the arytenoid, then diverge in order to form the sides of the ventricles, and then disappear in the aryteno-epiglottidean folds and even the under surface of the epiglottis. If we cut it away in successive layers, pro* We thus designate that part of the membrane which goes from the bottom of the vocal ligament, to the edge of the cricoid. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 406 ceedingfrom the outside to the in, we reach a thick bundle of fibres, perfectly horizontal, which linie the outer aspect of the vocal ligament, and which go from the anterior apophyses of the arytenoid to the re-entering angle of the thyroid*. IThis bundle has its posterior half covered by the lateral cricoarytenoid muscle, and its anterior half by the diverging fibres which start from the thyroid. If we cut away the horizontal bundle in successive layers, we see that the fibres are not all of the same length; the most external fibres are the longest, and the succeeding ones get gradually shorter as they become more internal; but they all originate in the anterior cavity of the arytenoid, and the muscle is inserted in the manner above explained throughout. the whole length of the vocal ligaments, the thyro-arytenoid portion of it excepted. As the fibres all begin from the arytenoid, and terminate successively at more distant points of the membrane, we see that the muscle is thicker behind than before. Thus the vocal ligamient, and the membrane which depends from it, the sole sources of all vocal sounds, are under the direct action of the fibres which come from the anterior cavity of the arytenoid; the ligament under the action of the horizontal bundle, the membrane under that of the oblique fibres. The long horizontal fibres, extending from one cartilage to the other, are placed at the exterior of the short horizontal fibres, and at the interior of the oblique fibres. The diverging fibres which start from the thyroid, acting only on the superior vocal ligaments and the folds, seem to influence by their contractions only the quality and volume of the voice. The remarkable arrangemnent of the fibres which we have just examined, enables us to explain a fundamental fact,-the elevation of the voice. The fibres of the horizontal bundle 1-eing placed over each other, in layers, one covering the other, and getting gradually longer and longer, as they becomne more external, extend their action to the more anterior parts of the edges of the glottis. This progressive action from the back to the front, encroaches gradually on the length of the vibrating portion of the ligament, and likewise increases its tension, and its faculty of accelerating its pulsations. Another portion of the thyro-arytenoid muscle at the same time stretches and raises the vocal memibrane mnore and more, causing a * Aniother portion of the thyro-arytenoid nmuscle. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 407 lesser depth of the ligaments to be in contact, in proportion as the sounds become higher, and thus assists by increasing the mobility of the ligaments. We shall see in a few moments that the rotatory movement, which the external fibres of the lateral crico-arytenoid muscles give to the arytenoid, by making the vocal membrane deeper, partly counteracts the above effect, and produces the chest-register. The crico-thyroid muscle, on the contrary, is a powerful auxiliary in the elevation of the voice. This muscle, which at the same time causes the thyroid to come forwards and downwards, gives rise to a mechanical tension, not only in the vocal ligament, but even in the whole vocal membrane. The meeting of the thyroid and cricoid cartilages, which we can feel by the touch, becomes especially marked when the inter-ligamentous glottis alone produces the sounds, which takes l)lace as we have seen at the notes do:, re, _ 3 3 in the chest-register, and an octave above fo this difference, however, that for the latt complete connexion is necessary. Let us now see what we may learn from the sensations we feel in the vocal organ. When we produce a chest-note, the least attention enal)es us to distinguish a "pinching " at the posterior part of the glottis, which becomes more vigorous as the notes ascend. This pinching seems to be formed by extension of the depth of the touching surfaces, and may become very painful; whilst the notes of falsetto, when higher than chest ones, give comparatively great relief to this part, and the surfaces in contact seem to have become thinner. If we combine these sensations with the different remarks which have been furnished to us by the examination of the muscles, we can fix the particular mechanism of each register. Chest Register. In fact, when the arytenoid muscles have brought in contact the arytenoid cartilages, and closed the glottis, the voice may take two very different characters ; nay, more, it will be produced in pitches widely apart from one another, and will give forth the chest, or falsetto registers, according as the fibres of the thyro-arytenoid attached to the vocal membrane are active or not. By the action This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 408 of these fibres, as we have seen, this muscle raises the vocal membrane, and makes its apposable part thinner; whereas the lateral crico-arytenoid gives a rotatory movement to the cartilage, which brings the apophyses into deep contact. This deep contact, which continues even after the apophyses no longer partake in the vibrations, gives a deep tension to the membranes, increases tlle depth of their contact*, and, as a necessary consequence, augments the resistance they present to the air. It is to the extent of this resistance that we attribute the formation of the chest-register, so distinct by its particular amplitude. 'ro it we attribute also the slowness of the beats of the glottis, and the consequent low pitchl of the sounds, a pitch which, even in the highest tenor voices, is at least an octave lower than the head notes of ordinary soprani. Register of Falsetto. When, on the contrary, the external fibres of the lateral cricoarytenoid muscle remain inactive, we produce the falsetto. 'lThe lips of the glottis, stretched by the horizonital bundle of the thyroarytenoid, come in contact by their edge alone, formed at once by the ligament and the apophyses, and offer little resistance to the air. Hence arises the great loss of this agent, and the general weakness of the sounds produced here. But as soon as we reach the sound do, the beats are produced by 4 the ligaments exclusively, and we have attained the head-register. It is certain, as we may deduce from the movement of the ligaments, that then the vocal membrane is raised by the action of the fibres of the thyro-arytenoid muscle, and its surface is diminished to an edge; but we think that the external fibres of the lateral crico-arytenoid, which would prevent this movement, remain inactive. Then also the very decided tension, which the crico-thyroid muscle effects on the vocal tendons, and which accelerates their movements, takes place. During the chest-register, therefore, the vocal ligaments are stretched, and are in contact to an extent corresponding with the depth of the anterior apophyses of the arytenoid, whilst in the falsetto the edges alone of the ligaments are stretched and apposed; in both cases the sounds being formed, not by the actual vibrations * It is then that we feel the pinching of which we have spoken. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 409 of either the whole or part of the tendons, but by the successive explosions whiclh they allow. Pressure of the Air. Until now, in our remarks on the manner in which the voice is formed, we have only referred to the rigidity of the glottis, a rigidity necessary to accomplish the 1056 vibrations in one second*, which form the do of the chest-voice, and to accomplish the double number 4 which produces the octave above in the head-voice. There is, notwithstanding, another indispensable element for the production of vocal sounds, the pressure of the air. Pressure, as is well known, developes an elastic force in this agent, in a degree inverse to the volume which it occupies. It is by means of this power that the intensity of the sounds is obtained. The intensity of the sound can only depend on the quantity of air which goes to each sharp explosion. I say sharp explosion, as an express condition: the glottis should close itself perfectly after every vibration; for if the air found a constant passage, as in the notes of falsetto, then the greatest movements of the glottis, and the greatest waste of air, would produce precisely the weakest notes. To reject this theory would be to attribute the intensity of the sound to the extent of the vibrations accomplished by the lips of the glottis, and to suppose that these lips, each taken separately, possess the power of producing sounds, suppositions quite contrary to the facts. The elastic force of the air arises not only from the compression of the lungs, but also from the contractions of the trachea, which adjusts its calibre to the different dimensions of the glottis. It is by means of this force that the air conquers the continually-increasing obstacle presented by the lips of the glottis when they produce sounds more and more intense. Thus the problem of the elevation of the voice, always complicated with that of its intensity, in order to be complete, ought to show the connexion which exists between the tension of the lips of the glottis, the pressure of the air, and the number and intensity of the explosions obtained. As a consequence, we may state that the greater pressure of air necessary to produce the greater intensity, * Pouillet, Physique, Sixth Edition, vol. iie page 77. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms 410 would at the same time increase the number of pulsations, and so raise the tone; but to prevent this, the glottis must at the same time be lengthened, and vice versa; or, in other words, that the different lengths of the glottis can, under different degrees of pressure, produce the same number of shocks, but at different degrees of intensity. Of the Qualities of the Voice. Various simultaneous causes modify the qualities of the voice 1, according as the glottis partially or entirely closes the passage between the explosions, it produces veiled or brilliant sounds; 2, the tube which surmounts and surrounds it also greatly affects the quality of the voice; by its contractions it gives brilliancy to it and its widening volume; 3, the epiglottis also plays a very important part, for every time that it lowers itself, and nearly closes the orifice of the larynx, the voice gains in brilliancy; and when, on the other hand, it is drawn up, the voice immediately becomes veiled. This content downloaded from 147.251.172.106 on Sun, 23 Feb 2020 08:49:20 UTC All use subject to https://about.jstor.org/terms