THE TELEPHONE AND HOW IT WORKS. 569 



dangerous practice of ' tapping the wires,' which may make it useful 

 or dangerous, according as it is used for proper or improper purposes. 

 It might be an important addition for a military commander to make 

 to his flying cavalry ; as an expert sound-reader, accompanying a col- 

 umn sent to cut off the enemy's telegraph-connections, might precede 

 the act of destruction by robbing him of some of his secrets. The 

 rapidity and simplicity of the means by which a wire could be 

 ' milked,' without being cut or put out of circuit, struck the whole of 

 the party engaged in the various trials that are described above. Of 

 course, the process of tapping by telephone could not be carried out 

 if the instrument in use was an A B C or single needle, or if the wire 

 was being worked duplex or with a fast-speed Morse, for in these 

 cases the sounds are too rapid or too indefinite to be read by ear. 

 The danger is thus limited to ordinary sounder or Morse telegraphs ; 

 but these still form the mainstay of every public system. 



" Since the trials above described were made, the newspapers have 

 recorded a beautiful application, by Sir William Thomson, of the elec- 

 tric part of the telephone to exhibit at a distance the motions of an 

 anemometer; the object being to show the force of air-currents in 

 coal-mines. This is a useful application of an electric fact, and doubt- 

 less points the way to further discoveries. But it is to be noticed 

 that the experiment, interesting as it is, hardly comes under the head 

 of a telephone, what is reproduced at a distance being not sound but 

 motion. 



" Obviously the invention cannot rest where it is ; and no one 

 more readily than the practical telegraphist will welcome an instru- 

 ment at once simple, direct, and reliable. Even in its present form 

 the telephone may be successfully used where its wire is absolutely 

 isolated from all other telegraph-wires. But the general impression is 

 that its power of reproducing the sound must be intensified before its 

 use can become general, or come up to the popular expectation." 



The realization of so marvelous a device as the telephone cannot 

 fail to stimulate speculation as to where such wonders will stop. 

 If words may be converted into electricity and back again into 

 words, what is to hinder their being converted into something more 

 lasting than electricity something that will endure, so that spoken 

 words may be reproduced in the future exactly as spoken now; that 

 persons, though dead, may yet speak? What is to hinder? Nothing ! 

 The thing is already done ; the spirit of the Phonograph has taken 

 on more than a shadowy form, as will be explained to our readers 

 next month. And what next ? 



" Ah ! Science, give us one more link, 

 That we may hear our neighbors think." 



