into action a second galvanic circuit. ... I informed him that I had devised another 

 method of producing effects somewhat similar. This consisted in opening the 

 circuit of my large quantity magnet at Princeton, when loaded with many hundred 

 pounds weight, by attracting upward a small piece of moveable wire, with a small 

 intensity magnet, connected with a long wire circuit. When the circuit of the large 

 battery was thus broken by an action from a distance, the weights would fall, and 

 great mechanical effect could thus be produced, such as the ringing of church bells 

 at a distance of a hundred miles or more, an illustration which I had previously 

 given to my class at Princeton. . . . The object of Prof. Wheatstone, as I under- 

 stood it, in bringing into action a second circuit, was to provide a remedy for the 

 diminution of force in a long circuit. My object, in the process described by me, was 

 to bring into operation a large quantity magnet, connected with a quantity battery 

 in a local circuit, by means of a small intensity magnet, and an intensity battery at 

 a distance." " 



Under date of March 16, 1857, Henry transmitted to the Board of 

 Regents of the Smithsonian Institution a "statement in relation to the 

 history of the electro-magnetic telegraph" for the investigation of their 

 special committee. Referring in his letter to his 1849 deposition he 

 stated : 



" My testimony was given with the statement that I was not a willing witness, and 

 that I labored under the disadvantage of not having access to my notes and papers, 

 which were in Washington. The testimony, however, I now reaffirm to be true in 

 every essential particular." ^^ 



As a result of its investigations the Committee reported as follows: 



"We have shown . . . that Mr. Henry's deposition of 1849 ... is strictly cor- 

 rect in all the historical details, and that, so far as it relates to Mr. Henry's own claim 

 as a discoverer, it is within what he might have claimed with entire justice. . . . " ^^ 



7. Non-inductive Winding 

 The earliest reference to the use of the non-inductive winding by 

 Henry was in a verbal communication made by him January 16, 1835, 

 before the American Philosophical Society, a report on which was 

 published March, 1835. He described it in more detail in a paper 

 read February 6, 1835, as follows: 



"One of these ribbons was next doubled into two equal strands, and then rolled 

 into a double spiral with the point of doubling at the centre. By this arrangement 

 the electricity, in passing through the spiral, would move in opposite directions in each 

 contiguous spire, and it was supposed that in this case the opposite actions which 

 might be produced would neutralize each other. The result was in accordance with 

 the anticipation; the double spiral gave no spark whatever, while the other ribbon 

 coiled into a single spiral produced as before a loud snap. Lest the effect might be 

 due to some accidental touching of the different spires, the double spiral was covered 

 with an additional coating of silk, and also the other ribbon was coiled in the same 

 manner; the effect with both was the same." -" 



Faraday, in his paper read before the Royal Society January 29, 



^* Annual Report of Smithsonian Institution, 1857, pp. 111-112. 

 ^^ Annual Report of Smithsonian Institution 1857, p. 87. 

 ^^ Annual Report of Smithsonian Institution 1857, p. 98. 

 " SW, Vol. 1, p. 94. 



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