Historical Telephone Numbers
Should you find an old Springfield document or a newspaper in the attic that has no dates but does include a phone number, the following may help you narrow down the years that it was created.
Telephone numbers ranging from 1-3 digits first appear in the 1892-1893 City Directory.
Telephone numbers ranging up to 4 digits first appear in the 1905 City Directory.
Telephone numbers ranging up to 5 digits first appear in the 1917 City Directory.
Telephone numbers with standard 5 digits first appear in the 1950 City Directory.
Telephone numbers with a combination of two letters and five digits first appear in 1958.
Telephone numbers with numbers only first appear in 1968.
For more information about the telephone and Alexander Grahme Bell read The telephone gambit: chasing Alexander Graham Bell's secret by Seth Shulman.
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