94 nature's 



telegraphing at a distance. This paper stim- 

 ulated others, and it was reserved for our own 

 Joseph Henry, already referred to, to show not 

 only how to construct a magnet for long-dis- 

 tance telegraphy, but also how to adapt the 

 battery to the distance. He showed us that 

 by insulating the wire and using several layers 

 of whirls, instead of one, and by using enough 

 cells of battery coupled up in series to get 

 more voltage, as we now express it, it was 

 possible to transmit signals to a distance. He 

 not only set forth the theory, but he con- 

 structed a line of bell-wire 1060 feet lon^r ;m<l 

 worked his magnet by making the armature 

 strike a bell for the signals, which is the basis 

 of the modern " sounder." 



Nothing was needed but to construct a line 

 and devise a code to be read by sound, to have 

 practically our modern Morse telegraph. This 

 line Ww8 constructed in 1831. In 1835 Henry, 

 who was then at Princeton, constructed a line 

 and worked it as it is to-day worked, with a re- 

 lay and local circuit, so that at that period all 

 the problems had been worked out. But, like 

 the speaking-telephone in its early inception, 

 no one appreciated its real importance. II< nry 

 himself did not think it worth while to take 

 out a patent. Two years later the Secretary 

 of the Treasury sent out a circular letter of 

 inquiry to know if some system of telegraphic 

 communication could not be devised. The 



