JOSEPH HENRY, LL.D. 287 



The electro-magnetic telegraph was first invented 

 by me, in Albany, in 1830. ... At the time of 

 making my original experiments on electro-mag- 

 netism in Albany, I was urged by a friend to take 

 out a patent, both for its application to machinery 

 and to the telegraph ; but this I declined, on the 

 ground that I did not then consider it compatible 

 with the dignity of science to confine the benefits 

 which might be derived from it to the exclusive 

 use of any individual. In this perhaps I was too 

 fastidious." 



Professor Asa Gray well said, " For the tele- 

 graph and for electro-magnetic machines, what 

 was now wanted was not discovery, but invention ; 

 not the ascertainment of principles, but the devis- 

 ing of methods." Morse is not to be less honored 

 because somebody discovered the principle, which 

 he and others utilized for the race, any more 

 than Edison, Bell, and others, because Faraday 

 and Henry helped to make their grand work 

 possible. 



"My next investigation, after being settled at 

 Princeton," says Professor Henry, " was in relation 

 to electro-dynamic induction. Mr. Faraday had dis- 

 covered that when a current of galvanic electricity 

 was passed through a wire from a battery, a cur- 

 rent in an opposite direction was induced in a wire 

 arranged parallel to this conductor. I discovered 

 that an induction of a similar kind took place in 

 the primary conducting wire itself, so that a cur- 

 rent which, in its passage through a short wire 



