France 161 



M. Berthon has likewise devised a novel self-restoring drop, 

 in which the solenoid principle is utilised, perhaps for the first 

 time in telephonic work. The plan has not, however, received a 

 practical application. 



HOURS OF SERVICE 



These, as a rule, correspond with the hours of telegraphic 

 service, which are continuous in Paris and eleven of the other chief 

 towns, and generally extend from 7 or 8 A.M. till 8 or 9 P.M. in 

 the smaller places. But Aix, St.-Etienne, and Chalons are open 

 till midnight, and Rheims and Pauillac till 10 P.M. 



SUBSCRIBERS' INSTRUMENTS 



The arrangement by which subscribers were left to purchase 

 their own instruments has produced some curious results. Except 

 within very wide limits the type was not denned until recently, 

 anything that would work in with the existing switching arrange- 

 ments being at first admitted. The methods of switching prac- 

 tised by the Societe Generale des Telephones required battery 

 and not magneto ringers at the subscribers' offices, so that that 

 system obtained such a hold that it has had perforce to be con- 

 tinued, much to the dissatisfaction of the present engineers, who 

 would change it if they could on account of the great expense of 

 maintaining so many voltaic cells scattered over a large area. 

 There being 14,000 subscribers in Paris and suburbs, each using six 

 Leclanche cells, it follows that there are 14,000 x 6 = 84,000 cells 

 to maintain. This would be bad enough if they were collected 

 in one building, but when distributed irregularly over some sixty 

 square miles, the task is recognised as a formidable one. While 

 the Societe Generale held the ground, the subscribers' choice of 

 instruments was limited, since it would not allow any but those 

 of its own manufacture to be used ; but this restriction vanished 

 when the State took over the system, and the field was thrown 

 open to all. The wide market thus created gave rise to keen 

 competition between manufacturers and to a great multiplication 

 of types of instruments. Each maker had a type of his own, 

 which he pushed as the best, so that the uninstructed subscribers 



M 



