SCIENTIFIC AND TECHNICAL LABOURS TO 1860. 233 



truths. Indeed I can only think with a certain sense 

 of shame of the circumstance that, after establishing 

 the principle of the dynamo machine. I did not at 

 once hit upon the parallel connection of the two 

 halves of the coils with opposed induction, employed 

 in the "plate" machine, but was only led to it several 

 years later by Pacinotti's example. 



In the year 1854 telegraph engineers were greatly 

 excited by a statement which appeared in the Leipzig 

 Polytechnic Centralblatt. The statement was to the 

 effect that the Austrian telegraph official Dr. Gintl had 

 succeeded in telegraphing between Prague and Vienna 

 by means of the Morse apparatus simultaneously in 

 opposite directions through the same conducting wire. 

 This was said to have been accomplished by providing 

 the relays with two coils, through one of which the 

 main current passed, while at the same time an equally 

 strong local current passed through in the opposite 

 direction. This second circuit had to be closed by a 

 separate contact at the same moment as the main 

 current. Dr. Grintl however soon found that this path 

 did not lead to the desired end. because it was im- 

 possible to let two contacts actually occur at the same 

 moment, and because the interruption of the main cur- 

 rent taking place at the end of each signal could not 

 but disturb the current coming from the other side. 



o 



Gintl therefore abandoned this method and tried to 

 solve the problem by making use of Bain's electro- 

 chemical telegraph. His experiments then yielded a 

 better result, and betrayed him into the belief that two 



