DEVELOPMENT IN TELEPHONE SERVICE 



2 39 



stations. A small electric bell is placed in each subscriber's house or office, 

 having a hook projecting from its base on which the hand telephone is hung 



when not in use (Fig. 20). When the telephone is 

 removed this hook can be thrown either to the right 

 or left. When thrown to the right the line wire 

 on one side of the station is connected through the 

 telephones to the ground and the line on the other 

 side is opened, preventing any one on that side hear- 

 ing what is said. When thrown to the left the re- 

 verse is true. It is obvious that no person between 

 the two that are conversing can put his telephone in 

 circuit without breaking the line, and consequently, 

 interrupting the conversation. All other stations 

 on the circuit are notified that the line is being 

 used by the striker being away from the bell. In 

 this case the subscriber must not attempt to call or 

 use the telephone. The signaling is done by pressing 

 and releasing a knob the requisite number of 

 times. . . . 



On June 12, 1879, the parent Bell com- 

 pany sent out photographs and a circular de- 

 scribing ' our No. 1 standard central office strip 

 switch arranged for seventy-five circuits.' 



In November, 1881, Mr. T. D. Loekwood 



said : 



To make a good telephone exchange switchboard, 

 however, out of an ordinary telegraph switch, we 

 concede that considerable remodelling is necessary; 

 and after the first heat of invention was over, prac- 

 tical men began to look about them, to see the disad- 

 vantages they were laboring under and endeavor to 

 overcome them. It was seen that time and money 

 were, in telephone offices, the two main articles to be 

 economized. Time, because speed of connection is the 

 very life-blood of the business. Money, because in 

 many of the exchanges the telephone business was 

 managed and owned by men of little or no capital; 

 and, in others, the expense, in any case, would be great, and economy was neces- 

 sary to make anything at all out of the business. Soon, therefore, it became 

 obvious that the telephone switch must be compact; all the apparatus must be 

 easily and quickly under control; everything about it must be well made and 

 well put together; the motions required in a connection must be reduced to a 

 minimum, and yet the apparatus must be cheap. The cry of cheapness for a 

 long time obscured the vision of the practical man. 



In 1881 came the first of the multiple switchboards. This inno- 

 vation was arranged for grounded and later for metallic circuits, and 

 was designed to eliminate many of the causes tending to slow down the 

 service. Under the previous system each operator was compelled to 

 act as information bureau, and subscribers called by name rather than 

 by number. The introduction of the mutiple board made necessary the 

 assignment of numbers to subscribers, and many an urgent request to 

 call by number rather than by name. Thus the multiple-board operator 

 made connections only in response to requests giving numbers. If 

 complaints were made or information requested, the caller was 

 quickly switched to the information desk presided over by a special 

 operator. In the same manner the toll calls were handled at a toll 



Fig. 20. 



