A Magic Concert

Note: original spelling has been maintained.

IT is now somewhat more than two years ago since a Parisian savant astonished a number of his friends by inviting them to a concert performed by musical instruments whose keys were obviously untouched by human hands. The invitations were accepted; and at the appointed time the guests, most of them of decidedly sceptical tendencies, assembled at their host’s apartments, where they were ushered into a drawing-room of very modest dimensions, and presenting a perfectly ordinary appearance, in one comer of the room stood a small piano; and in the centre, raised on wooden supports, were placed a harp, a violin, and a violoncello. The visitors were requested to examine the walls and the adjoining rooms, in order to satisfy themselves that no musicians were concealed in them.

When all were convinced that no imposition of any kind was possible, the host proposed that the concert should begin. Taking a conductor’s baton in his hand, he struck one of the supports with it, and then began to beat time—one, two, three. Instantly the windows shook, the room trembled, and the audience rose stupefied and bewildered. The instruments were untouched, yet the sounds they produced were deafening; the effect being that of an entire orchestra playing in the room. The overture to “William Tell” was performed with the utmost precision, to the extreme amazement of the hearers.

“ That is more noisy than you like, perhaps?” suggested the host. “If you prefer it, you shall hear a quartette.” The signal was given by the baton, and a beautiful quartette was exquisitely rendered by the  piano, violin, violoncello, and voice.

One of the guests inquired if the musicians were hid in the rooms either above or below that in which they were assembled. Permission to investigate was immediately granted, and a search followed, which was utterly unsuccessful. One fact, indeed, was then ascertained—namely, that the music, which was heard so distinctly in the drawing room, was inaudible elsewhere in the house. This one little room alone possessed the power of producing these mysterious sounds.

“In order to prove that these sounds are really engendered here, I have had these instruments placed as you see them. You shall now hear them play alternately.” Scarcely had the savant uttered these words before the harp and violin—standing on their wooden supports—began one of Mendelssohn’s “ Lieder ohne Worte,” arranged as a duet Their exquisite harmonies were hardly ended, before the piano began the overture to “ Tannhauser,” which it performed in an animated but somewhat noisy style. The effect was magical, and the guests were utterly astounded.

The philosopher next proposed to do something still more marvellous.

“ I can, if you wish it,” he said, “ even make these little boards perform. This plank can, at your desire, sing, recite, beat a drum, or imitate any musical sound.”

The piece of wood was scarcely placed in the position previously occupied by one of the instruments, before the loud beating of a drum—as if it were calling an army to assemble preparatory to a charge—was heard in the room. On the plank being removed, the sound ceased; but on its being replaced, the drum beat as loudly as ever.

The plank was then caused to speak, which it did with the harsh, grating tones of a ventriloquist. Its shouts of laughter filled the room. On its being removed from its place, there was perfect silence; but when it was returned to its former position, it made the air resound with a mocking and derisive laugh.

These extraordinary phenomena were frequently repeated in the course of the evening, and on each occasion, with increased success. The host had thoroughly fulfilled his promise. He had unquestionably accomplished what most of his guests had previously considered to be impossible.

The auditors, aided by a heated imagination, were only too ready to attribute these phenomena to the intervention of some supernatural agency; while, in truth, the whole secret of the wonderful performance was to be found in well-known acoustic laws. It was based on the fact that sound travels with much greater rapidity-through solids than through air. Under ordinary circumstances, sound will travel through about 372 yards of air per second; while through the fibres of a piece of wood, in the same time, it would travel nearly 4,360 yards. The rapidity of its transmission varies considerably in the different kinds of wood. Thus, through acacia, it passes at the rate of 5,142 yards per second; through deal, 3,630 yards; through poplar, 4,670 yards; through oak, 4,200 yards; and through ash, 5,090 yards in the same time. Through some metals, the rapidity is still greater. An iron wire, for example, transmits it at the rate of 5,363 yards, and cast-steel at the rate of 5,436 yards, per second; while through brass its velocity is only 3,888 yards. In consequence of this rapid and accurately determined transmission of sounds through solids, the slightest vibratory motion applied to the end of a piece of wood is instantly communicated to its other extremity. The fact of the ticking of a watch, held at one end of a piece of wood, being distinctly audible at the other end, suffices to illustrate this principle.

Two persons at a considerable distance from each other can carry on a conversation, without even raising their voices, by means of a wire or a wooden rod, if the ends are held between the teeth of the speakers. Her hold, a Dane, frequently excited the curiosity of his friends by enabling them, with their ears stopped, to hear music from an harmonium played 250 yards distant from them. This he succeeded in doing by stretching a wire from the instrument to the hearer, who had to hold it in his teeth.

Laths of wood transmit sounds communicated to them, not only with great rapidity, but also without the slightest modification of pitch. Thus, if a lath, ten yards in length, is placed against the front of a house, and a tuning fork is struck and applied to its lower end, a similar tuning fork at its upper extremity will give exactly the same sound as the first. Fifty such forks may be used instead of two, and the lath may be of any length, and still the same results will be obtained. Consequently, every time that a wooden rod or lath is applied to the sounding-board of an instrument, it will transmit any notes produced by the instrument, causing the auditors to hear the sounds as clearly as if they were produced in their immediate vicinity.

A knowledge of these facts serves to explain the mystery of the Magic Concert. A small orchestra had been concealed in the area, and rods of deal connected the instruments there employed with those in the drawing-room where the guests were assembled — the wooden supports which have been mentioned being placed there as coverings to the upper ends of the rods. The guests, by these means, heard in the drawing-room upstairs the pieces of music which were performed in the area, the effect being precisely the same as if the musicians had been playing in their presence. This, briefly, is the explanation of this curious Parisian concert.

There is, however, one thing we should like to know—viz., was the ingenious host present at any of the lectures “On Sound,” delivered, in 1866, at the Royal Institution, by Professor Tyndall?

Can the following paragraphs from the concluding portion of Professor Tyndall's second lecture have suggested to the French philosopher the first idea of his Magic Concert?

“In a room underneath this, and separated from it by two floors, is a piano. Through the two floors passes a tin tube, 2 inches in diameter, and along the axis of this tube passes a rod of deal, the end of which emerges from the floor in front of the lecture table. The rod is clasped by india rubber bands, which entirely close the tin tube. The lower end of the rod rests upon the sound-board of the piano, its upper end being exposed before you. An artist is at this moment engaged at the instrument, but you hear no sound. I place this violin upon the end of the rod; the violin becomes instantly musical—not, however, with the vibrations of its own strings, but with those of the piano. I remove the violin: the sound ceases. I put in its place a guitar, and the music revives. For the violin and guitar I substitute this plain wooden tray: it is also rendered musical. Here, finally, is a harp, against the sound-board of which I cause the end of the deal rod to press: every note of the piano is reproduced before you. I lift the harp, so as to break its connection with the piano: the sound ceases; but the moment I cause the sound-board to press upon the rod, the music is restored. The sound of the piano so far resembles that of the harp, that it is hard to resist the impression that the music you hear is that of the latter instrument..

“What a curious transference of action is here presented to the mind! At the command of the musician's will, his fingers strike the keys; the hammers strike the strings, by which the rude mechanical shock is shivered into tremors; the vibrations are communicated to the sound-board of the piano; upon that board rests the end of the deal rod, thinned off to a sharp edge, to make it fit more easily between the wires. Through the edge, and afterwards along the rod are poured, with unfailing precision, the entangled pulsations produced by the shocks of those ten agile fingers. To the soundboard of the harp before you the rod faithfully delivers up the vibrations of which it is the vehicle. This second sound-board transfers the motion to the air, carving it and chasing it into forms so transcendentally complicated, that confusion alone could be anticipated from the shock and jostle of the sonorous waves. But the marvellous human ear accepts every feature of the motion; and all the strife, and struggle, and confusion melt finally into music upon the brain.”

We must leave our readers to draw their own conclusions. Unfortunately, the scientific world of France is generally so totally ignorant of the labours of German and English philosophers, that a plagiarism might be attempted with almost certain immunity from detection.