178 INDUCTION WRITING TELEGRAPH. 



In Germany however many of the views of Faraday, 

 particularly those of electrical distribution by molecular 

 induction, being incompatible with prevailing theories, 

 obtained but little credence. This induced me to study, 

 without regard to existing theories, the question of 

 electro-static induction, which was of extreme impor- 

 tance for telegraphy according to my earlier experience. 

 I finally obtained a complete confirmation of the views 

 of Faraday, for the correctness of which I was fortunate 

 enough to find new proofs. Unhappily being oftentimes 

 interrupted in my labours by my strenuous technical 

 activity I could not conclude my experiments before the 

 spring of 1857, when I summarised their results in a 

 paper published in Poggendorff's Annalen >k '0n electro- 

 static induction and the retardation of the current in 

 jar wires". 



It became clear to me from these experiments, 

 that only by employing short intermittent currents was 

 there any prospect of corresponding quickly on longer 

 cable-lines. In a paper "The induction writing-telegraph 

 of Siemens and Halske'' published in 1857 I described 

 the mechanical expedients for accomplishing this task. 

 They consisted essentially of a magnetically polarized 

 relay, which was so constructed that its armature, when 

 moved by a short impulse of current to the contact, 

 remained attached to this, until a short current in the 

 opposite direction carried it back to the insulated stop. 

 The short intermittent currents were generated in the 

 secondary coil of an inductor by the telegraphic cur- 

 rents being sent through the primary coils of the same. 



