fcow tbe {Telephone aath0. 149 



methods of transmission. One is the magneto 

 method the one we have described and the 

 other is effected by varying the resistance of 

 a battery current. The former will work with- 

 out a battery, as the voice acting on the wire 

 around the magnet through the diaphragm 

 creates the current; in the latter the current 

 is created by the battery but molded by the 

 voice. In the latter method the current passes 

 through carbon contacts that are moved by the 

 diaphragm. Carbon is the best substance, be- 

 cause it will bear a wider separation of con- 

 tact without actually breaking the current. 

 When carbon points are separated that have 

 an electric current passing through them, there 

 is an arc formed on the same principle as the 

 electric arc-light. 



Great improvements in details have been 

 made in the telephone since its first use, but 

 no new principles have been discovered as ap- 

 plied to transmission. 



\\V have spoken in another place regarding 

 the various claimants to the invention of the 

 telephone, but here is one that has been over- 

 looked. A young man from the country was 

 in a telegraph-office at one time and was left 

 alone while the operator went to dinner. Sud- 

 denlv the Bunder -tarted up and rattled away 

 at such a rate that the countryman thought 

 hin^ -hoiiM he dune. Ho leaned down 

 close to i h- iiMnnnent and shouted as loudly 



