42 PROFESSOR HENRY AND THE 



" of a current from a trough is at least not sensibly 

 " diminished by passing through a long wire, is 

 11 directly applicable to Mr. Barlow's project of 

 " forming an electro-magnetic telegraph."* This 

 reference was to Barlow's paper of 1824, in 

 which he had demonstrated the impracticability 

 of the telegraph. 



Had these things been done in the Royal Institu- 

 tion, and read before the Royal Society, Wheatstone 

 would not have been found, in 1837, denying the 

 possibility of an electro-magnetic telegraph ; and 

 Faraday would have been able to answer Cooke's 

 question, without sending him to Wheatstone for 

 the information. In those days, however, the 

 United States were held in no higher estimation in 

 Europe, than Nazareth was in former days in 

 Jerusalem ; and no one in England read an 

 American book. 



But not content with having reasoned out, and 

 demonstrated, that distance was no longer the sole 

 impediment in the way of the magnetic telegraph, 

 Henry, in 1831, established the first electro- 

 magnetic telegraph that ever existed. In the 

 Albany academy he strung a mile of line wire, 

 and with an "intensity battery " at one end, and his 

 spool of long fine wire at the other, he operated the 

 armature of the first sounding telegraph of any 

 kind. When the armature was attracted by 



* See Appendix, Note R. 



