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Path: utzoo!watmath!clyde!burl!ulysses!gamma!exodus!bambi!schatz
From: schatz@bambi.UUCP (Bruce R. Schatz)
Newsgroups: net.games.trivia
Subject: Re: phone-number taxonomy
Message-ID: <34@bambi.UUCP>
Date: Wed, 4-Jul-84 02:03:05 EDT
Article-I.D.: bambi.34
Posted: Wed Jul  4 02:03:05 1984
Date-Received: Mon, 9-Jul-84 00:56:14 EDT
References: <248@homxa.UUCP>, <3738@fortune.UUCP>
Organization: Bell Communications Research;  Short Hills, NJ
Lines: 10

according to the official source
"Engineering and Operations in the Bell System"
from which all we old telephone engineers learned our
stuff, telephone numbers are divided into two parts:
 exchange (3 digits) and line (4 digits).
as mentioned in earlier messages, station is a variant name of line.
the exchange identifies the central office and the line
identifies the subscriber line.
the old alphabetic code were indeed cheery but didn't correspond to
the internal use which was always 3 and 4 not 2 and 5.