instrument—a string of definite length, density, and tension is made to correspond to each note, and to give out the right number of vibrations when its key is struck.

It is possible to bring about a visual expression of musical vibrations, under certain conditions. Take a common piece of board about forty-two inches long, a piece of fine brass wire, or, better still, a violin or guitar string about sixty inches long, a tape-measure, and two triangular bits of wood an inch and a half long on the vertical side and with an inch base. Tack the tape-measure on the board, beginning the yard three inches from the end of the board, or mark off thirty-six inches on it. Place a screw eye at each end of the board at its middle point, and you are ready for a very simple experiment which will illustrate the point better than many words and elaborate figures. Set up the two bridges, the vertical sides towards each other (Fig. 1), at the ends of the measured yard. Fasten the wire to one screw-eye, and, letting it pass over the two bridges and through the second screw-eye, weight it by fastening a flatiron on the overhanging end. Having put some bits of paper cut in a Y shape astride the string, set the string into musical vibration by gently plucking it at its middle point. It will swing back and forth past the dotted line which indicates its position when at rest, taking positions A a A and A a' A (Fig. 2) in rapid succession. The paper riders are thrown by the vibration. Now touch lightly with the finger the point over the number 18 and pluck the string at 27. The light touch of your finger, or even of a feather, will serve as the fret does on the guitar- there are now two strings practically half the former length. Instead of vibrating as a whole, like A, it first takes the position IB, and then 2B, and back and forth, going from one to the other with lightning-like rapidity. It is easy to see that the middle point of the string is comparatively motionless; such a point of rest in musical vibration is called a node. The riders remain on the node, but are thrown from the vibrating segments. A gave out a certain note; B, being half as long, gives out a note an octave above A. Again put the riders on the wire, touch with a feather the point 27, and pluck the string half-way between 27 and 36 (Fig. 1); the touch at 27 makes of that point a node, but besides that it makes a node at 18 and at 9. The string c (Fig. 2) is practically one-fourth as long as it was at first; it has four vibrating or ventral segments and three nodes, and is equal to four nine-inch strings vibrating together. Putting the riders along the string you will see that they settle at the nodes c d and are thrown violently off from the vibrating segments. The apparatus is so rough that the nodes are not really points

of rest, and the riders may not stay on, but the agitation is manifestly very much less at the nodes than on the ventral segments of the string. With the apparatus described I have succeeded a number of times in agitating the string so that the riders on the nodal points remained while those on the ventral segments were all dismounted.

A string is a very simple vibrating body and moves only in one vertical plane, but it serves, for that very reason, as the best illustration of vibrating segments and nodes.

In the movement of в and c from position 1 to 2 there is not the violent reversal that there appears to be the wave generated by the pull at a (1 B and I c) runs along the string to the end, and from that point it is reflected back in the direction 2 B and 2 c. If the attempt is made to touch the string, or dampen it, as it is technically called, at any point not an exact divisor of 36, the result would have been a joggle, not a vibration; the wave would not have reached the far end of the wire in the right phase to be reflected back regularly.

So far we have only been considering the simplest vibrations, a single wave running back and forth on a string; but in sound-waves, as in water-waves, motion is superposed upon motion, ripples upon waves, in an inconceivable complexity. If we could produce by the sonorous body only such simple vibrations as these we have been examining, all musical instruments, including the human voice, would sound exactly alike, so far as quality is concerned. The only possible difference would be in range and intensity. We could not distinguish the notes of a French horn from those of a guitar. Simple vibrations constitute only the fundamental tone, which is the same for the identical note on all musical instruments.

Tyndall in his book on sound says: "It has been shown by the most varied experiments that a stretched string can either vibrate as a whole, or divide itself into a number of equal parts, each of which vibrates as an independent string. Now it is not possible to sound the string as a whole without at the same time causing, to a greater or less extent, its subdivision; that is to say, superposed upon the vibrations of the whole string we have always, in a greater or less degree, the vibrations of its aliquot parts. The higher notes produced by these latter vibrations are called the harmonics of the string. And so it is with other sounding bodies; we have in all cases a coexistence of vibrations. Higher tones mingle with the fundamental one, and it is their intermixture which determines what, for want of a better term, we call the quality of the sound." And again, later on, he says: "Pure sounds without overtones would be like pure water, flat and

FIG. 3. CHLADNI PLATE.

dull. The tones, for example, of wide-stopped borgan-pipes are almost perfectly pure. . . . But the tones of such pipes, though mellow, would soon weary us; they are without force or character, and would not satisfy the demand of the ear for brightness and energy. In fact, a good musical clang requires the presence of several of the first overtones. So much are these felt to be a necessity that it is usual to associate with the deeper pipes of the organ shorter pipes which yield the harmonic tones of the deeper one. In this way, where the vibrating body itself is incapable of furnishing the overtones, they are supplied from external sources." In fact, the ear demands that each note shall be a harmonic chord, powerfully dominated by the fundamental tone though it may be.

The determining value in the overtones of an instrument was felt, practically, long before their existence was known in theory. Makers of musical instruments learned long ago how to quench certain objectionable overtones, even before they knew just what they were doing. Imagine what the air would look like if it could be made visible when an orchestra is setting it into vibration, with thousands of tones and their attendant overtones crossing and recrossing with infinite complexities of form. The different notes are not each making its separate mark, but all have combined, helping or hindering one another, and coming as a single full harmony to the ear, where there is a resolution of the composite movement; and this marvelous "lute of three thousand strings" takes up the tangled skein of sound, separates it into its constituent tones, and conveys them separately to the brain.

The idea of getting a visual expression for musical vibrations occurred to Chladni, a physicist of the last century. He fastened a plate of glass by its center, and then, having scattered some sand over the surface, threw it into sonorous vibrations by means of a violin bow. Imagine the delight with which he saw the sand stir and form into line on the plate, forming a star of twelve rays. Square plates of glass or metal screwed or even glued to a central support can be made by the merest tyro with tools, and give wonderful results (Fig. 3). A plate, like a string, has one rate of vibration which belongs to it, but again, like a string, by "dampening" it with a touch of the finger or fingers in different points along the edge the note changes and with it the figure made by the sand. The lines on the plate where the sand settles are the nodes, the lines of comparative rest. The violent agitation in the parts left bare

can be shown by mixing a little lycopodium powder with the sand; this is excessively light, and is caught in the little whirlwinds of air generated about the vibrating segments.

The marvelous intricacy of the vibrations of these plates may be seen from a few figures given below, which indicate the lines taken by the sand when certain notes were sounded on the plate (Fig. 4).

A little instrument invented by Professor Sedley Taylor, and called the phoneidoscope, gives a most exquisite illustration of music made visible. It consists of a tube which terminates in a hollow cup or funnel-shaped enlargement; over the mouth of this funnel a thin sheet of metal or pasteboard with a smoothedged and symmetrical opening is made. Across the opening a film of soap-suds is drawn and left to stand till colors begin to form. These soap-bubble colors, as is very well known, are due to the thickness of the film. In an ordinary soap-bubble they flit over the surface irregularly. This is because from the exposed outer surface of the bubble, and the irregular force which is expanding it from within, the film is always varying in thickness. The colors tell inexorably just how much this variation is at every point of the surface. A special fluid, made very carefully, is necessary for experiments with the phoneidoscope, because the soap-film must thin sufficiently to show bright colors and yet be strong enough to stand the vibrations into which it is thrown by the voice.

When the colors are well established in the film a sustained musical note should be sung

FIG. 4.

into the open end or mouthpiece of the tube, using care not to breathe or blow into it. The colors begin to move, and, if the note is sustained, whirl into the most beautiful gyrating figures. Mr. Behnke, in a discussion before the Musical Association of England, says: "I have for many years tried to get what help I could from science in the treatment of the human voice, and when Professor Sedley Taylor some years ago brought this phoneidoscope under my notice I was very highly delighted. He told me it would be possible by means of a soap-film to get dif ferent figures for different pitches, for different

intensities, and for different qualities of tone.... I did not find the phoneidoscope answer in practice. In the first place there was great difficulty about these films, which would continually burst. In the second place there was no doubt I did get a variety of figures, and not only that, but a variety of exceedingly beautiful colors. The experiments were most fascinating; but I did not get the same figures regularly for the same changes in either pitch or intensity or quality, and therefore, so far as practical results were concerned, the instrument was of no use. . . . Of course it does not follow because we have not yet succeeded in these matters we never shall."

We are now upon the very threshold of Mrs. Hughes's voice-figures, and have reached it by the same path which brought her to them in the first instance. Her eidophone is constructed on the same principle as the phoneidoscope: instead of the frail lamina of soap-suds she has a stretched membrane of india-rubber to receive the vibrations, and on this is spread a thin layer of some pasty substance which will retain the record made by the vibrations of the membrane. These voice-flowers are not the simple visual forms corresponding with the vibrations of the air set in motion by the voice. The waves generated in the closed bowl of the eidophone are reflected again and again from the sides of the vessel. The volume of air inclosed has its own rate of vibration; the stretched membrane has also its own rate, which in turn is modified by the character and thickness of the paste spread upon it. Added to these are molecular forces of cohesion and adhesion between the particles of paste, and again between the paste and the membrane. The form which grows into shape is the resultant of all these complicated forces, and, in some instances,

new elements of change have been added. A glass plate is placed on top of the vibrating membrane and moved over it. We have a new body introduced with its proper rate of vibration, besides a mechanical motion further to complicate the problem.

The results are very wonderful and beautiful, and open up a field for investigation which is most interesting, but so far we have the resultant of many forces, not one of which has been weighed and measured. In a letter from Mrs. Hughes, replying to some questions asked in the hope of greater accuracy, she says: "The notes producing the figures vary necessarily with the weight of material used and the tension of the membrane, so that any one note may, under different circumstances, produce different figures, and, conversely, different notes may, under different circumstances, produce similar figures."

The daisy forms were sung into shape, she says, by extremely low notes very softly sounded, some of them by A in the first space of the bass clef- a wonderful note to be reached by a woman's voice, whose highest note is the B-flat above the treble clef, a com: pass of over three octaves. Sometimes geometrical forms not given in the illustrations were produced by the highest notes of her voice, while the serpent, fern, and tree forms were made by singing her middle notes with great intensity.

Mrs. Hughes is first of all a singer, and to further her voice culture she entered upon the series of experiments in which she has shown infinite patience and skill. That her experiments are amateurish rather than scientific is no discredit, for she has opened up a new field into which the scientist may enter and reach results of great interest and value.

IN

Sophie B. Herrick.

-

Maurice Francis Egan.

"I hate it most of all for Phillida's sake," Philip went on. "It cannot be a happy marriage. Here they've gone and engaged them selves without reflection, and a catastrophe is sure to follow."

"Oh, maybe not," said Mrs. Gouverneur, who could not help feeling that Philip partly blamed her for the engagement.

"Why, just look at it. They have n't really kept company. He has been going to dinner and dancing parties this spring, and she to Mackerelville Mission and Mrs. Frankland's Bible Readings. If they should discover their incompatibility before marriage it would n't be so bad; but he 's off to Europe for the summer, and then they 'll be married in the autumn, probably, and then what? Phillida will never spend her time dancing germans with Charley; and he would make a pretty fist running a class of urchins in Mackerelville. I tell you it only means misery for both of them." And with this prediction Philip mounted to his own room. Millard was too busy with the packing of trunks, the arrangement of business, and goodby visits to Phillida, to give much thought to Philip's curious behavior; but it troubled him nevertheless. And when, on the deck of the steamer Arcadia, he bade good-by to a large circle of friends, including Mr. Hilbrough, who brought a farewell bouquet from his wife, and Mrs. Callender and her daughters, he looked about in vain for Philip. He could no longer doubt that for some reason Philip disliked his engagement. But when the last adieus had been waved to diminishing and no longer disringuishable friends on the pier, and the great caty had shrunk into the background and passed from view as the vessel glided steadily Forward into the Narrows, Millard entered his cabin and found a package of guide-books and a note from Philip excusing his absence on the ground of a headache, but hoping that his friend would have a pleasant voyage and expressing hearty good wishes for his future with Phillida. It was all very curious and unlike Philip. But the truth below dawned upon Charley, and it gave him sorrow that his great joy might be Philip's disappointment.

tage of priority. Like the family that dwelt within, it maintained a certain dignity of repose that could well afford to despise decoration and garniture, and look with contempt on newness. The very althæas, and lilacs, and clambering jasmines in the dooryard and the large trees that lent shade to a lawn alongside, bespoke the chronological superiority of the place. There was no spruceness of biweekly mowing about the lawn, no ambitious spickand-spanness about the old, white, wooden, green-blinded cottage itself, but rather a restful mossiness of ancient respectability.

Here Philip watched out the lazy September days, as he had watched them since he was a lad. This was a Newport afternoon, not cloudy, but touched by a certain marine mistiness which took the edge off the hard outlines of things and put the world into tone with sweet do-nothingness. Half-sitting, half-lying, in the wide piazza chair, clearly not made to measure for him, Philip had remained for two hours, reading a little at intervals, sometimes smoking, but mostly with head drawn down between his shoulders while he gazed off at the familiar trees and houses, noted the white-capped maids with their infant convoys, and the infrequent carriages that rolled by. His mother, with her fingers busy at something of no consequence, sat near him. Each was fond of the other's presence, neither cared much for conversation. Gouverneur, the father, was enjoying a fine day in his fashion, asleep on a lounge in the library.

"It's just as I expected, mother," said Philip, coming out of a prolonged reverie. "Charley and Phillida will marry without ever getting acquainted, and then will come the blow-out."

แ

"What do you mean by the blow-out?" said Mrs. Gouverneur. "They are neither of them quarrelsome."

"No; but they are both sensitive. Aunt

Callender's sickness took Phillida to the Catskills before he got home, and she's been there ever since. I suppose he has gone up once or twice on a Saturday. But what chance has

either of them to know the other's tastes? What

after the m

of age outstripped by youth, inexpugnable advan

are married? I'd like to see him persuade

tainments and the opera. Maybe it'll be the other way; she may coax him to teach a work