Some years after Chanot’s Violin had been consigned to the department of the museum specially devoted to this object, Felix Savart, a physicist of eminence, struck with the discoveries of Chladni on the communication of vibrations and regularity of sonorous waves, devoted himself with great ardour to the application of these discoveries in the construction of bow instruments, and after several experiments, made with great sagacity, he arrived at the following deductions:—1st, When two or a larger number of bodies, whatever they may be, come into immediate contact, and one is directly put into motion, they all produce the same number of vibrations at the same time; 2nd, All these vibrations follow parallel directions; 3rd, The increase of the sound of any kind of body—for example of a string—depends upon the simultaneity of the vibrations of the bodies with which this string is in contact; and this increase is carried to its highest point when the bodies put into motion by communication are in such conditions that, if they were directly put into motion, they would produce the same number of vibrations as the body acted upon in the first instance.
The chief consequences of these principles are, that the vibrations produced by the strings of the Violin are communicated to the belly by the bridge, from the belly to the back by the sounding-post; and that the oscillations, in equal number, of all these bodies, cause equal vibration, and, by similar numbers of oscillations, to the mass of air held in suspension within the body of the instrument; hence it follows that the object in the construction of this sonorous box is to favour as much as possible the communication of the sound-waves, and to bring them into harmony. In seeking the application of this theory to the manufacture of bow instruments, Savart fell into error in the first pamphlet he wrote upon this subject,[B] when he expressed the opinion that the curves, the angles, and the raised belly adopted by the old manufacturers could only have proceeded from the prejudices of routine; but he discovered this error while prosecuting the continuation of his studies, and he ultimately extolled the proportions of Stradiuari, which he first believed to be only favourable to good effects from considerations which the celebrated maker had not perceived.
A manufacturer of the greatest intelligence, M. Vuillaume, sen., born at Mirecourt, and settled in Paris, devoted himself to the principles of constructing bow instruments, at the very time Savart was occupied in endeavouring to discover them. These two ingenious men, in constant communication with each other on this subject, reciprocally aided each other. The artist brought to the man of science the tribute of his experience, and the man of science to the artist the result of his meditations. Vuillaume had been for a lengthened period engaged in experiments on the density, homogeneity, and the elasticity of various woods, convinced of the importance of this matter for the solution of most of the problems of acoustics relative to the sonorous quality of instruments. He was thus enabled to discover the most suitable wood to be used in the repairing of ancient instruments, as regards their quality or their defects, and the most signal success crowned his researches. Many instruments of great price, after having been deteriorated by unskilful hands, recovered their former value through the ability of this distinguished maker. What he acquired in this respect, he applied to all instruments of his own manufacture, and his deep study of the proportions of the best ancient instruments, joined to his knowledge of the special nature of woods, and the laws of vibration, has enabled him to produce a multitude of very superior instruments, which require only time to be stamped with excellence.
It will be seen, from what has been said, that the art of constructing bow instruments has departed from the prejudices of routine, working in the dark, and by imitation, to pursue the wake of science, of observation, and of calculation. There can be no doubt that this is a real progress; but to shield this progress from all contestation, the effect of time is requisite. To bring a good instrument to that state of equilibrium which will make its qualities manifest, on the one hand it is necessary that the materials employed in its construction should, for a lengthened period, be submitted to the action of the various states of temperature and atmosphere; and on the other, that the elasticity of its various parts should have been put for a long time into action, to acquire all its development.
