File:Bell telephone magazine (1922) (14756315972).jpg

Identifier: belltelephonemag19amerrich (find matches)
Title: Bell telephone magazine
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company American Telephone and Telegraph Company. Information Dept
Subjects: Telephone
Publisher: (New York, American Telephone and Telegraph Co., etc.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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doubtedly be Chicago.The illustration is interesting as show-ing the extent to which the primaryoutlets already are connected directlywith Chicago, over one-half of themhaving such direct connection. Future growth will doubtless leadto an increase in the number of tollcenters connected directly to a re-gional center. By this process therewould be a continued growth in thenumber of toll centers which can beinterconnected with a maximum oftwo intermediate switches. JLooKiNG to the future, an increas-ing amount of the outgoing traffic willbe handled by operators in the localcentral offices, reaching the toll lineover toll tandem trunks. It is evi-dent, however, that the ultimate solu-tion of the problem will involve theuse of machine methods for the selec-tion of the toll line by the operators,as is now done in certain segregatedtoll tandem systems. The entire trend of recent yearsis thus to decrease the differences be-tween the handling of exchange mes-sages and of toll messages. At the
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FIGURE 6 Direct circuits radiating from Chicago 56 Bell Telephone Quarterly JANUARY present time more than 90 per centof the toll messages are completedwhile the subscriber remains at thetelephone, with speeds of completiononly slightly slower than those ofexchange messages. Transmissionstandards, while naturally somewhatbetter for the shorter distances in-volved in exchange messages, are,nevertheless, rapidly becoming verycomparable. The present view oftrends for the future is for continua-tion of this process, perhaps even tothe use of similar types of machineequipment at central offices forswitching the various classes of mes-sages. Transcontinental Routes and theDevelopment of Carrier Systems In order to justify the reference totranscontinental telephony which iscontained in the title of this talk, Imust return to it from time to time. Ido so again at this point to mentionthat the original line with three cir-cuits has now become four routes withabout 170 circuits. You have doubt-

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