180 ANNUAL OF SCIENTIFIC DISCOVERT. 



VIBRATIONS OF SOUND RENDERED VISIBLE. 



M. Treves has made the follo^^^ng curious mechanical experi- 

 ment : Two steel tuning-forks, brought to the same pitch, were 

 topped with small mirrors, and placed opposite to each other in 

 2 vertical planes at right angles. One of them, No. 1, was, 

 moreover, surrounded with a strong coil of wire, receiving an 

 electric current from a nitric acid pile composed of 4 elements. 

 A fiddlestick being now drawn across each of the tuning-forks, 

 the vibrations commenced, and immediately a perfectly motion- 

 less luminous circle was produced in the mirror of No. 2. But no 

 sooner was No. 1 magnetized by the admission of the current, 

 than the circle became an ellipse, and swayed to and fro, denoting 

 the action of a new vibratory motion. As soon as the current 

 ceased the figure became a fixed circle again. This experiment 

 may serve to investigate the vibratory powers of iron and steel 

 according to their composition and physical state. — Galignani. 



INSTRUMENT FOR ANALYZING SOUNDS. 



An instrument has been exhibited before the Academy of Sci- 

 ences, called by its inventor, M. Daguin, an "analyzing cornet." 

 Wliat we describe as noise is of course made ujj of an infinite 

 number of musical notes, and these the cornet is designed to ana- 

 Ij'ze, just as a prism separates a ray of white light into its colored 

 components. In appearance the instrument resembles a trumpet, 

 having a nozzle to fit into the ear instead of a mouth-piece, and 

 furnished with holes like a clarionet. Provided with one of these 

 instruments, the roaring of a cataract or the howling of the win- 

 ter's blast may be resolved by the listener, skilled in the neces- 

 sary fingering, into the softest melody, which, of course, is heard 

 only by himself. 



MUSICAL TELEGRAPH. 



Mr. Wm. Boyd, of Cambridge, Mass., has invented and matured 

 a system of telegraphy by sound, which may yet be brought into 

 famihar use. The special feature of the scheme is the adoption 

 of the 4 sounds of the common chord of the natural major key (or 

 the corresponding notes of any other major key), namely, C, E, 

 G, C, or do, mi, sol, do, or 1, 3, 5, 8 ; the last being the mode by 

 which they are designated in this alphabet. These 4 sound letters, 

 never more than 3 being used at once, admit of a variety of 84 

 combinations, representing the letters, points, marks, figures, and 

 word-contractions which compose the alphabet. The letters and 

 points most frequently used are represented by the lowest num- 

 bers, and consequently the fewest sounds. For instance, the 

 letter E is represented by the tone 1 or C ; T, by the tone 3 or G ; 

 O is made by the combination 11 or CC; K requires 3 sounds, 



