310 Telephone Systems of the Continent of Ettrope 



SWITCHING ARRANGEMENTS AND SUBSCRIBERS' 

 INSTRUMENTS 



The necessity for multiple boards has not yet been felt 

 [traffic is small in Portugal, the calls averaging only two per line 

 per day at Lisbon, and four at Oporto], and the service is carried 

 on by simple boards manufactured by the Consolidated Tele- 

 phone Construction and Maintenance Company, London. These 

 are of three types : (i) a 5o-line modified cross-bar, peg com- 

 mutator, mounted vertically, with the indicators above ; (2) a 



FIG. 105 



FIG. 106 



FIG. 107 



ioo-line board of the same nature, but mounted horizontally, 

 with the indicators on a vertical board at the back ; (3) a ioo-line 

 spring-jack and plug and cord board, the general arrangement 

 of which resembles that of the Western Electric Standard board, 

 but without ring-off indicators. The first and third are used at 

 Lisbon, the second at Oporto. In all three speaking has to be 

 carried on through two indicators, which both fall when a ring 

 through or ring off is given. Each operator usually attends to 

 seventy-five subscribers, but in Oporto during the busy hours this 

 number is reduced to fifty. Magneto ringers are exclusively used. 



