Bell's- Telephonic Researches 



forks of different pitch to vibrate simultaneously 

 by means of an electric current. Mr. Ellis was 

 kind enough to grant me an interview for the 

 purpose of explaining the apparatus employed 

 by Helmholtz in producing these extraordinary 

 effects, and I spent the greater part of a delight- 

 ful day with him in investigating the subject. 

 At that time, however, I was too slightly ac- 

 quainted with the laws of electricity fully to 

 understand the explanations given; but the in- 

 terview had the effect of arousing my interest in 

 the subjects of sound and electricity, and I did 

 not rest until I had obtained possession of a copy 

 of Helmholtz 's great work " The Theory of Tone, " 

 and had attempted, in a crude and imperfect 

 manner, it is true, to reproduce his results. While 

 reflecting upon the possibilities of the production 

 of sound by electrical means, it struck me that 

 the principle of vibrating a tuning fork by the 

 intermittent attraction of an electro-magnet 

 might be applied to the electrical production of 

 music. 



I imagined to myself a series of tuning forks 

 of different pitches, arranged to vibrate auto- 

 matically in the manner shown by Helmholtz 

 each fork interrupting, at every vibration, a 

 voltaic current and the thought occurred, Why 

 should not the depression of a key like that of a 

 piano direct the interrupted current from any 

 one of these forks, through a telegraph wire, to 

 a series of electro-magnets operating the strings 

 of a piano or other musical instrument, in which 

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