THE PHONOGRAPH, OR VOICE-RECORDER. 295 



they inherit from savage and brutal ancestors. But here- 

 after, when the representatives of the brutality and savagery 

 of our nature are held in proper disesteem, and those who 

 have added new enjoyments to life are justly valued, a high 

 place in the esteem of men will be accorded to him who has 

 answered one half of the poet's aspiration, 



" Oh for the touch of a vanished hand, 

 And the sound of a voice that is still I " 



NOTE. Since the present paper was written, M. Aurel deRatti has 

 made some experiments which he regards as tending to show that there 

 is no mechanical vibration. Thus, " when the cavities above and below 

 the iron disc of an ordinary telephone are filled with wadding, the 

 instrument will transmit and speak with undiminished clearness. On 

 placing a finger on the iron disc opposite the magnet, the instrument 

 will transmit and speak distinctly, only ceasing to act when sufficient 

 'pressure is applied to bring plate and magnet into contact. Connecting 

 the centre of the disc by means of a short thread with an extremely 

 sensitive membrane, no sound is given out by the latter when a message 

 is transmitted. Bringing the iron cores of the double telephone in con- 

 tact with the disc, and pressing with the fingers against the plate on the 

 other side, a weak current from a Daniell cell produced a distinct click 

 in the plate, and on drawing a wire from the cell over a file which 

 formed part of the circuit, a rattling noise was produced in the instru- 

 ment." If these experiments had been made before the phonograph 

 was invented, they would have suggested the impracticability of con- 

 structing any instrument which would do what the phonograph actually 

 does, viz. , cause sounds to be repeated by exciting a merely mechanical 

 vibration of the central part of a thin metallic disc. But as the phono- 

 graph proves that this can actually be done, we must conclude that M. 

 Aurel de Ratti's experiments will not bear the interpretation he places 

 upon them. They show, nevertheless, that exceedingly minute vibra- 

 tions of probably a very small portion of the telephonic disc suffice foi 

 the distinct transmission of vocal sounds. This might indeed be inferred 

 from the experiments of M. Demozet, of Nantes, who finds that the 

 vibrations of the transmitting telephone are in amplitude little more than 

 i -zoooth those of the receiving telephone. 



