80 L. Scliwendler — Discharge of long Telegraph lines. [No. 1, 



events, produce points instead of bars at the receiving station, 

 thereby causing considerable delay and confusion. 



It is true that in principle the arrangement in use at terminal 

 stations might also be applied at translation stations, where the 

 armatures of the sounders, or any other receiving instruments, act 

 as keys ; but there are many mechanical difficulties in the way, 

 especially the very small play of these armatures which would 

 make such a method unsafe. It was, therefore, decided to use for 

 translation stations another discharging arrangement, which I will 

 now describe. This arrangement consists of a Siemens' polarized 

 relay with comparatively small resistance, and of a small bobbin 

 of wire acting as a shunt to the coils of the relay, which latter may 

 appropriately be called the " Discharging relay." The parallel 

 circuit of discharging relay and bobbin of wire is interposed be- 

 tween the line to be discharged after each signal and the sending 

 battery. 



The contact screw of the discharging relay is connected with one 

 end of the receiving relay, while the axis of the tongue of the dis- 

 charging relay is in connection with the other end of the receiving 

 relay, i. e. the earth. Such an arrangement may be of course 

 applied equally well for terminal stations in place of a discharging 

 key, and as the telegraph circuit for two terminal stations is of 

 a simpler nature than the translation circuit, it will be clearer to 

 explain the action of this discharging arrangement for two terminal 

 stations working direct with each other, as for instance, Calcutta 

 and Agra. 



The following diagram (Fig. 1) will give all the necessary con- 

 nections. 



CALCUTTA 



Ti£:l 



