245 



Tho paper gave rise to a discussion on the popular de- 

 lusions of the day, and especially on the so-called system 

 of spiritualism, in which Prof. Henry, Dr. Hough, Prof. 

 McCoy and others took part. 



Prof. Hall called attention to the fact in connection with 

 the visit of Prof. Henry, that in 1832 he had witnessed in 

 this building, illustrations by Prof. Henry of his results in 

 electro-magnetism. He saw here a wire of great length, 

 through which Prof. Henry transmitted a current of gal- 

 vanic-electricity, and made the current to exert its power 

 in ringing a bell at the extremity of the wire. This was 

 certainly the first establishment of the practicability of 

 the magnetic telegraph. 



Prof. Henry stated that he felt himself gratified at this 

 public recognition of his early labors and discoveries in re- 

 ference to the electric telegraph, especially as he had been 

 subjected to unjust imputations as to his claims. For him- 

 self he had always been ready to accord most cheerfully to 

 Prof. Morse the credit of contriving the most convenient 

 and simple kind of a telegraph. To the attacks on himself 

 he had not replied for reasons which would appear here- 

 after. But he begged his friends to be assured that he did 

 Hot mean to suffer such a stain to remain on his memory. 

 In due time a full exposition and vindication would appear. 



The Institute then adjourned. 



January 19, 1858. 



The Institute met, the president in the chair. 



John E. Gavit, in reference to the discussion at the last 

 meeting in regard to Prof. Henry's agency in the discovery 

 of the magnetic telegraph, proceeded to explain that Prof. 

 Barlow of Woolwich, England, in 1824, had announced to 

 the scientific world, that it was impossible to force the 

 galvanic current through a wire longer than three miles. 

 Prof. Henry by his experiments in 1829 and 30, showed this 

 conclusion to be false, that by using a battery of intensity 

 instead of quantity, a current could be projected through a 



[Trans, iv.] 33 



