PROFESSOR JOSEPH HENRY'S INVEN- 

 TION OF THE ELECTRIC TELEGRAPH 



[In 1855 the Regents of the Smithsonian Institution, 

 Washington, D. C., at the instance of their secretary, Pro- 

 fessor Joseph Henry, took evidence with respect to his 

 claims as inventor of the electric telegraph. The essential 

 paragraphs of Professor Henry's statement are taken from 

 the Proceedings of the Board of Regents of the Smithsonian 

 Institution, Washington, 18573 



THERE are several forms of the electric tele- 

 graph; first, that in which fractional electricity 

 has been proposed to produce sparks and motion 

 of pith balls at a distance. 



Second, that in which galvanism has been em- 

 ployed to produce signals by means of bubbles 

 of gas from the decomposition of water. 



Third, that in which electro-magnetism is the 

 motive power to produce motion at a distance; 

 and again, of the latter there are two kinds of 

 telegraphs, those in which the intelligence is in- 

 dicated by the motion of a magnetic needle, and 

 those in which sounds and permanent signs are 

 made by the attraction of an electro-magnet. 

 The latter is the class to which Mr. Morse's in- 

 vention belongs. The following is a brief ex- 

 position of the several steps which led to this 

 form of the telegraph. 



The first essential fact which rendered the 

 electro-magnetic telegraph possible was dis- 

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