Belgium 



79 



berghe system compels the adoption of a few special features, such 

 as the phonic call and alarm, wi W2 are the two wires of a metallic 

 circuit coming from the condensers of a Van Rysselberghe tele- 

 graph line, wi leads through the jack ji and thence through the 

 coil PI of the phonic call to the plug FI and, by its base contact, 

 through the secondary coil TI of the translator to earth. W2 goes 



FIG. 17 



through the jack J2, the coil P2 of the phonic coil, the plug F2 and 

 its base contact to the other secondary T2 of the translator to 

 earth. A calling current from a distant station splits between 

 the two wires and follows the course indicated. A branch is 

 taken off at a through the Dewar key DI to the indicator MI 

 (which is wound to 1,000 ohms and is unaffected by the phonic 

 call currents) and the base contact strip of the plug FI. De- 



