MACHINE SWITCHING TELEPHONE SYSTEM 59 



quired to introduce the new system completely, we can expect little 

 or no reduction in the present operating forces for some time to come, 

 and no operator will find herseli out ot employment on account of the 

 introduction of the machine switching system. 



Machine Switching 



It is the purpose of this paper to describe this system sufficiently 

 in detail to give a general picture of it, but because of the limitation 

 as to space no attempt will be made to go into the intricacies of cir- 

 cuits and apparatus, which doubtless would be of interest only to the 

 telephone engineering specialists. 



Among other requirements, the following must receive special 

 consideration in the design of a machine switching system. 



The functions to be performed by the telephone subscriber in getting 

 a connection must be simple and easily understood. 



It must work efficiently and with accuracy and speed, and, of 

 course, must be capable of handling the various types of calls that the 

 subscriber wishes to make. 



The system must not require modifications in the existing rate 

 structure, otherwise than desirable. If the rate structure calls for 

 message register operation, coin boxes, etc., means must be provided 

 for automatically operating the register and collecting the' coins on 

 such calls, and for preventing a charge on calls not answered, calls 

 for free lin?s, busy lines, etc. 



The system should employ, as nearly as practicable, the conven- 

 tional numbering scheme. 



It should work with the existing telephone network, so that its 

 introduction does not require wholesale number changes and extensive 

 rearrangement or the abandonment of existing switchboards or other 

 plant. Its introduction must, of necessity, be on a gradual basis. 



It must be sufficiently flexible in design to care for growth and such 

 changing traffic conditions as occur from time to time. 



In large telephone areas, such as the New York Metropolitan area, 

 there is a great variety of calls to be handled and many different classes 

 of service furnished the public, such as message rate, flat rate, official, 

 coin box, non-attended pay station, attended pay station, special 

 services such as information, etc. Not only individual lines but party 

 lines, and private branch exchanges must be cared for, and provision 

 must be made for thousands of toll messages which must be recorded, 

 supervised and timed. 



A call originating in a machine switching office in New York City 

 may have as its destination any one of a great number of points. It 



