32 * . THE ELECTRIC TELEGRAPH. 



35. Ga.uss and Weber's line, as has been said, was 

 erected between the Physical Cabinet and the observatories 

 of Gottingen for other than telegraph purposes. It was for 

 this reason that Gauss, unable to afford the time necessary 

 to perfecting the system, which he believed capable, with 

 modifications, of leading to brilliant results, requested Pro- 

 fessor Steinheil, of Munich, to simplify the apparatus and 

 endow it with a practical application. 



The perfection to which this ingenious inventor brought 

 Gauss and Weber's telegraph has rendered it as much or 

 more his than theirs. He studied thoroughly the subject 

 of magneto- electricity, and made experiments, discoveries, 

 and suggestions which earned for him the name of the 

 founder of electro-magnetic telegraphy. 



A description of this telegraph by its inventor is to be 

 found in Dingler's Journal, 70, p. 292. 



It consists principally of three parts the inductor, the 

 receiving apparatus, and the line. 



The compound permanent magnet employed by Steinheil in 

 his apparatus consisted of seventeen horseshoe magnets, 

 weighing together 60 Ibs., capable of lifting about five times 

 its own weight. Two induction coils, of together 15,000 con- 

 volutions of insulated copper wire, turned on an arbor, and 

 presented in rotation the axes of the coils to the poles of 

 the magnet, so that when one coil was under the north 

 end of the magnet, the other would be under the south 

 end. The commutator in connection with these coils was 

 so constructed that, in turning them from right to left, 

 the alternate currents, or all those going in one direction 

 only, passed through the line, and, on turning them back- 

 wards or from left to right, only those currents in the 

 opposite direction were let into the circuit, the others being 

 cut off. 



Steinheil was careful to admit his currents for the shortest 

 possible space of time, and for this purpose, allowed the 

 contact springs of his commutator to make contact with 

 the lines only at the moment when the induced current was 

 at its maximum. Fig. 15 represents the contact plate to 



