Masterpieces of Science 



core, for the effects were equally audible when the 

 battery was omitted and a rod of magnetized 

 steel substituted for the iron core of the magnet. 

 It was my original intention, as shown in Fig.3, 

 and it was always claimed by me, that the final 

 form of telephone would be operated by perma- 

 nent magnets in place of batteries, and numer- 

 ous experiments had been carried on by Mr. 



Fig. ii 



Watson and myself privately for the purpose of 

 producing this effect. 



At the time the instruments were first exhibited 

 in public the results obtained with permanent 

 magnets were not nearly so striking as when a 

 voltaic battery was employed, wherefore we 

 thought it best to exhibit only the latter form of 

 instrument. 



The interest excited by the first published ac- 

 counts of the operation of the telephone led many 

 persons to investigate the subject, and I doubt 

 not that numbers of experimenters have inde- 

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