Identifier: bell00systemvol31techniamerrich (find matches)
Title: The Bell System technical journal
Year: 1922 (1920s)
Authors: American Telephone and Telegraph Company
Subjects: Telecommunication Electric engineering Communication Electronics Science Technology
Publisher: (Short Hills, N.J., etc., American Telephone and Telegraph Co.)
Contributing Library: Prelinger Library
Digitizing Sponsor: Internet Archive

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y other office in the same numbering plan area. Thus each ofthe 50,000,000 telephones in the United States and Canada will have, fortoll dialing purposes, a distinct identity consisting of ten digits; a three-digit area code, an office code of two letters of an office name and anumeral, and four digits of the station number within the office. Typicalnumbers for toll dialing would therefore be 601-CA3-4567 or 317-MA7-6789. As with operator toll dialing, on a toll call which terminates in thesame numbering plan area in which it originates, the area code will beomitted and the office code and station number^—a, total of seven digitswill be used. With this universal 2-5 type of number, local calls in and about thelarger and medium sized exchanges will be completed by dialing theentire seven-digit number. For many of the smaller places in the moreisolated sections, 5-digit or 4-digit dialing will frequently be employedwhere this number of digits will be adequate for all of the telephones
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