29 AUGUST 1891, Page 25

VOICE-FIGURES.* hr his commendatory preface to Mrs. Watts Hughes's interesting

description of the Voice-Figures with which her name is associated, Mr. Walter Besant says :—" I have looked anxiously for some printed account of the phenomena : I have hoped that some mathematician or physicist might have his attention directed to these experiments." If the mathe- maticians and physicists have heretofore ignored a very pro- mising and fascinating field of inquiry, we are sorry for their neglect, and hope that it will not be further prolonged ; but it certainly lacks the excuse suggested by the first half of Mr. Besant's sentence. Nearly two years ago, Mrs. Russell Barrington contributed to these columns a letter giving a very full and interesting description of the voice-figures and the method of their production, and still more recently, in an article entitled " Music and Form,"t we recapitulated the salient facts of Mrs. Watts Hughes's experi- ments, and indicated one goal of discovery towards which they might possibly tend. In the Century, and, if our memory does not deceive us, in the Leisure Hour also, attention has been drawn to these things of strangeness and of beauty ; but though Mrs. Watts Hughes's brochure deals, therefore, with matters not wholly unfamiliar to some readers, it is not on that account less welcome, and is, indeed, of unique value as the statement of the one person who can speak with the authority of a discoverer and practical experimentalist.

The voice-figures, many of which are, we believe, to be seen at Mrs. Watts Hughes's Home for Little Boys at Islington, are produced by directing the singing-voice, through a tube or cylinder constricted for the purpose, against an elastic membrane, upon which has been placed some powder or pig- ment, generally suspended in a liquid vehicle which leaves it free to obey any impulse of movement which may be com- municated to it. When the,.sound-waves of a, sustained vocal note strike the membrane, they produce regular vibrations by which any finely divisible substance lying upon the membrane is first distributed into the definite arrangements that consti- tute these figures, some of which are geometrical designs of frequent complexity and nava:trying symmetry, while others— and these are the more remarkable and interesting—are wonderfully close reproductions of some of the most beautiful forms in Nature,—flowers, trees, ani she The novelty of Mrs. Watts Hughes's experiments lies partly in her methods and partly in their results, especially in the production of these pictorial or representative figures which suggest previously undreamed-o' possibilities of relation between sound and form. That some relation exists between the two was long ago demonstrated, and since the discovery of the physical method of the transmission of sound, might have been established independently of experiment by a priori reasoning. Interesting and conclusive experiments have, however, not been wanting. A century or more ago, as Mrs. Watts Hughes points out, Chladni "ascertained that the vibrations of plates in the act of giving forth musical notes (when set vibrating by drawing a violin-bow across their edges) caused powder strewn upon them to form regular patterns, and these have been known since as Chladni's figures." Much more recently, "Professor Sedley Taylor has exhibited by his phoneidoscope the crispations of a soap-film set in vibration by a vocal sound;" and Mrs. Watts Hughes might have mentioned the very different but not less sug- gestive phenomena exhibited by Professor Tyndall's " sensi- tive flames," the best description of which known to us is given in a singularly interesting letter written by Lady Pollock and published in the Correspondence of Sir Henry Taylor.

These voice-figures, however, represent a new departure in experiment; and though Mrs. Watts Hughes in her mono- graph confines herself strictly to a description of her methods of operation and of the results already achieved, it is im- possible not to feel that she has taken the first:steps into what may prove a new fairyland of wonder. In refraining from speculation concerning future possibilities of discovery or generalisation, Mrs. Watts Hughes displays the cautious reserve of the true scientific mind; and the only omission which can reasonably be regretted is the absence of any account of the primal suggestion—probably some happy accident—which had for its result the first of her long series • VoicaFigures. By Mrs. Watts Hughes. London : Haze% Watson, and Viney. t Speetabr, May 16th, 1881. of experiments,—the something which was to her what the

bath was to Archimedes, the apple to Newton.

Mrs. Watts Hughes has an advantage denied to us in being able to utilise both the pencil and the pen, for without the aid of pictorial illustration it is manifestly impossible to give anything like an adequate impression of the appearance pre- sented by the voice-figures ; but even an incomplete description of their prominent features will suffice as an introduction to what is at once a scientific exposition and a fascinating picture-gallery. Perhaps the point which first claims atten- tion is the entire absence from the processes of any arbitrary or chance element. The results attained are strictly scien-

tific, because constant, inevitable, calculable. By reproducing with exactitude given conditions of experiment, the precise

figure which was formed yesterday can be formed to-day or to-morrow ; and every variation between figures intended to be identical, records some difference "either in the character or quantity of the substance used ; in the form, the quality, or the tension of the elastic membrane the vibrations of which evoked it ; or in the pitch, intensity, or quality of the vocal note that created those vibrations." Of course, the perfect co-operation of these varying factors in bringing about a desired result can only be attained by often-repeated and carefully conducted experiments ; but when the required knowledge is attained, it would seem that the draughtsman- ship of the voice is not less certain, not less under absolute control, than the draughtsmanship of the pencil.

It is clear, however, that in the former the complexity of the conditions, so difficult to master, often results in disappoint- ments which have at first an appearance of inexplicability, though further experiment always suffices to bring the apparent

exception under the reign of law. In her account of experi- ments in which she employed as a vehicle lycopodium, the

impalpably fine seeds of the puff-ball, Mrs. Watts Hughes records a significantly interesting experience of initial failure and ultimate success :-

`° When, upon one occasion, singing notes with which I had many times previously produced figures with perfect ease, I witnessed a curious phenomenon. All at once the disc became unusually agitated, and instead of the customary figure appearing, the lycopodium flew hither and thither all about the surface of the disc, at one moment as if struggling to shape itself into the regular figure, and at another moment as if trying to form a different figure. While perplexed to account for this un- usual wavering of the disc another sustension of the same note abated the excitement, and left on the disc the figure I had looked for. I noticed, however, that thelintensity of the last note was less than that of my previous efforts. I therefore concluded that the cause of the unusual commotion was the presence of over- tones, through singing too loudly. Singing then the octave above, I at once saw before me the very figure which had been struggling for predominance with its companion octave below. By repeated experiments I have since found that every figure requires not only its exact pitch, but also its exact intensity, although such intensity will admit of a certain degree of crescendo and diminuendo. Any intensity beyond that requisite to cause the lycopodium to cover the whole of the vibrating circle is likely to excite over-tones, and so to prevent the accurate formation of the figure belonging to the tone itself."

This is very curious and interesting; but there is no part of Mrs. Watts Hughes's brief monograph which is devoid of fascination for those who love to follow the footsteps of pioneers in the unexplored territory of the wonderland of science. The plates represent specimens of all the various kinds of figures, both those which are produced directly by the action of the voice on the vibrating disc, and those which are, as it were, transferred—though that is hardly the right word —from the disc to a rigid surface. What may be called the representative figures have certainly in the greatest degree the charm of strangeness. Why, among all possible forms, the notes should wed themselves to some of the most familiar and lovely forms of Nature, is a question which may never be answered; or, on the other hand, it may some day receive an answer that will pour a flood of light upon the hidden methods by which God in the creative process works towards ends of beauty. At any rate, what Mrs. Watts Hughes has to tell and to show us is as rich in fascinating suggestiveness as in positive interest and instruction.