Telephone exchange names
A telephone exchange name was a distinguishing and memorable name assigned to a telephone exchange. In multi-exchange service areas, exchange names identified the central office to which a telephone was connected. Each exchange served a maximum of 10,000 subscriber lines identified by the last 4 digits of the telephone number. Areas or cities with more subscribers were served by multiple exchanges, possibly hosted in the same central office building. Abbreviations of the exchange names were used as leading components of telephone numbers, so that each telephone number in an area was unique.
In exchange areas with dial service, the leading letters of exchange names were mapped to digits. The letters were typically displayed on the telephone dial by grouping the letters around each digit. Several systematic coding schemes for telephone numbers existed in various communities, sometimes evolving over time as the subscriber base outgrew older telephone numbering plans. A widely used numbering plan was a system of using two letters from the exchange name with five digits, which was designated as 2L-5N. In 1917, W. G. Blauvelt of AT&T proposed a mapping system that displayed three letters above the digits 2 through 9 on the dial.
Telephone directories or any other telephone number displays typically listed the telephone number showing the significant letters of the exchange name in bold capital letters, followed by the digits that identified the subscriber line. On the telephone instrument's number card, the exchange name was typically shown in full, but only the significant letters were capitalized, while the rest of the name was shown in lower case, or as small caps (as TAylor 4725).
The system of telephone exchange names was over time retired after the introduction of area codes in the United States and other similar all-number calling systems around the world, such as the British all-figure dialling.
United States and Canada
In the United States, major cities such as New York, Philadelphia, Boston, and Chicago first used a system designated 3L-4N, using three letters and four digits. These numbers were converted to the later system of 2L-4N. Eventually these were changed to 2L-5N. For example, under this system, a number in New York City was shown as PEnnsylvania 6-5000.
From the early 1920s through the 1930s, the Bell System installed the Panel switch in large metropolitan areas and by the 1950s twenty cities were served by this type of office. The prototype panel exchanges were installed in New Jersey (Mulberry and Waverley) in 1915. Initially the technology appeared, from the telephone user's viewpoint, as no change at all from the customary way of making a call; the customer asked an operator to ring their called party. However, unbeknownst to the caller, on her switchboard, the operator was keying the number into the panel equipment.
From the time of these first conversions to automated equipment in the 1920s, through the conversions of most manual equipment by the 1960s, it was necessary for telephone numbers to be represented in a uniform way. Bell System policy was that customers should never need to be concerned about whether they were calling an automated or a manual exchange. The 2L-5N system became the North American standard, as customer-dialed long distance service, known as Direct Distance Dialing, came into use in the 1950s.
The standard format for displaying telephone numbers which used exchange names was to capitalize the first few letters which were dialed, for example:
- BALdwin 6828 (typical urban North American before move to two-digit exchange names)
- MArket 7032 (typical urban North American six-digit phone number, from the 1920s through the 1950s; phased out throughout the 1950s)
- MUrray Hill 5-9975 (one of the Ricardos' numbers on I Love Lucy. Note that the H in Hill, although not dialed, is still capitalized)
- ENglewood 3-1234 (typical North American, gradually implemented continent-wide, from the late 1940s)
In print, such as on business cards or in advertisements, the full exchange name was often abbreviated, with a period used to indicate the abbreviated form, an example being:
- TEmpleton 1-6400 would appear as TE 1-6400.
If the letters were not dialed, it was common to capitalize only the first letter of the exchange name (e.g., "Main 600W" or "Fairmont 33"). Such numbers could be of non-standard length, because they were not dialed, but quoted to an operator who manually connected the customer to the appropriate line. However, in general such short numbers were used only in the smallest areas.
A large city with coexisting manual and dial areas would generally standardize numbering. For example, when the last San Francisco manual exchange was converted to dial in 1953, the numbers had for several years been in the format of JUniper 6-5833. Customers calling from JUniper 4 to JUniper 6 would dial the number, which was then displayed to the incoming B-board operator, who'd manually complete the connection. A caller in the manual JUniper 6 office returning the call to the JUniper 4 office would lift the receiver and wait for the operator, who would plug a cord into her multiple, and dial the number.
During the 1950s, cities using six-digit numbers converted to seven-digit dialing. Typically, several six-digit (2L-4N) exchanges were co-located in one building already, with new ones added as old ones had filled up. After the conversion, They were then combined into a new 2L-5N exchange. For example, the CHerry, FIllmore, ATwater, and KLondike exchanges might be converted to OXford 1, 3, 6, and 7. Usually customers would keep the same line numbers.
|2||A B C|
|3||D E F|
|4||G H I|
|5||J K L|
|6||M N O|
|7||P R S|
|8||T U V|
|9||W X Y|
In 1955, AT&T distributed a list of recommended exchange names that were the result of studies to minimize misunderstandings when spoken. The recommendation was intended for newly established exchanges, and did not mandate any renaming of existing historical names. The number sequences 55x, 57x, 95x, and 97x had no exchange names specified, as the mappings for the digits 5, 7, and 9 had no vowels, thus making it difficult finding names with those consonant combinations. As a result, those numbers were originally never assigned to exchanges. On the telephone dial, letters were mapped to digits using the assignments in the table (right).
The recommended list of exchange names was:
- 22x: ACademy, BAldwin, CApital, CAstle
- 23x: ADams, BElmont, BEverly, CEdar, CEnter, CEntral
- 24x: CHapel, CHerry, CHestnut, CHurchill, CIrcle
- 25x: ALpine, BLackburn, CLearbrook, CLearwater, CLifford, CLinton
- 26x: AMherst, ANdrew, COlfax, COlony, COngress
- 27x: BRidge, BRoad(way), BRown(ing), CRestview, CRestwood
- 28x: ATlantic, ATlas, ATwater, ATwood, AVenue, BUtler
- 29x: AXminster, AXtel, CYpress
- 32x: DAvenport, DAvis, EAst(gate), FAculty, FAirfax, FAirview
- 33x: DEerfield, DEwey, EDgewater, EDgewood, EDison, FEderal
- 34x: DIamond, DIckens, FIeldbrook, FIeldstone, FIllmore, FIrestone
- 35x: ELgin, ELliot, ELmwood, FLanders, FLeetwood
- 36x: EMerson, EMpire, ENdicott, FOrest, FOxcroft
- 37x: DRake, DRexel, ESsex, FRanklin, FRontier
- 38x: DUdley, DUnkirk, DUpont, EVergreen, FUlton
- 39x: EXbrook, EXeter, EXport, EXpress
- 42x: GArden, GArfield, HAmilton, HArrison, HAzel
- 43x: GEneral, GEneva, HEmlock, HEmpstead, IDlewood
- 44x: GIbson, GIlbert, HIckman, HIckory, HIllcrest, HIlltop
- 45x: GLadstone, GLencourt, GLendale, GLenview, GLobe
- 46x: HObart, HOmestead, HOpkins, HOward, INgersoll
- 47x: GRanite, GReenfield, GReenleaf, GReenwood, GRidley, GRover
- 48x: HUbbard, HUdson, HUnter, HUntley, HUxley, IVanhoe
- 49x: GYpsy, HYacinth, HYatt
- 52x: JAckson, LAfayette, LAkeside, LAkeview, LAmbert, LAwrence
- 53x: JEfferson, KEllogg, KEystone, LEhigh, LEnox
- 54x: KImball, KIngsdale, KIngswood, LIberty, LIncoln, LInden
- 56x: JOhn, JOrdan, LOcust, LOgan, LOwell
- 58x: JUniper, JUno, JUstice, LUdlow, LUther
- 59x: LYceum, LYndhurst, LYnwood, LYric
- 62x: MAdison, MAin, MArket, MAyfair, NAtional
- 63x: MEdford, MElrose, MErcury, NEptune, NEwton, NEwtown
- 64x: MIdway, MIlton, MIssion, MItchell, NIagra
- 65x: OLdfield, OLive, OLiver, OLympia, OLympic
- 66x: MOhawk, MOntrose, MOrris, NOrmandy, NOrth(field)
- 67x: ORange, ORchard, ORiole, ORleans, OSborne
- 68x: MUrdock, MUrray, MUseum, MUtual, OVerbrook, OVerland
- 69x: MYrtle, OWen, OXbow, OXford
- 72x: PAlace, PArk(view), PArk(way), RAndolph, RAymond, SAratoga
- 73x: PErshing, REd(field), REd(wood), REgent, REpublic
- 74x: PIlgrim, PIoneer, RIver(side), RIver(view), SHadyside, SHerwood
- 75x: PLateau, PLaza, PLeasant, PLymouth, SKyline
- 76x: POplar, POrter, ROckwell, ROger(s), SOuth(field)
- 77x: PRescott, PResident, PRospect, SPring, SPruce
- 78x: STate, STerling, STillwell, STory, SUffolk, SUnset,
- 79x: PYramid, SWathmore, SWift, SWinburne, SYcamore
- 82x: TAlbot, TAlmadge, TAylor, VAlley, VAndyke
- 83x: TEmple(ton), TEnnyson, TErminal, TErrace, VErnon
- 84x: THornwell, TIlden, VIctor(ia), VIking, VInewood
- 85x: ULrick, ULster, ULysses
- 86x: TOwnsend, UNderhill, UNion, UNiversity, VOlunteer
- 87x: TRemont, TRiangle, TRinity, TRojan, UPtown
- 88x: TUcker, TUlip, TUrner, TUxedo
- 89x: TWilight, TWinbrook, TWining, TWinoaks
- 92x: WAbash, WAlker, WAlnut, WArwick, WAverly
- 93x: WEbster, WEllington, WElls, WEst(more), YEllowstone
- 94x: WHitehall, WHitney, WIlliam(s), WIlson, WIndsor
- 96x: WOodland, WOodlawn, WOodward, WOrth, YOrktown
- 98x: YUkon
- 99x: WYandotte, WYman, WYndown
Fictitious phone numbers starting with 55 used the fictitious exchange name KLondike (55). The letters Q and Z were never used in the naming system, but Z was often mapped on the telephone dial to the digit 0 (zero).
As demand for phone service grew in the post-World-War-II period, it was foreseeable that it would exceed the addressing capacity of the existing system of using memorable telephone exchange names as prefixes for telephone numbers. Several letter combinations had no pronounceable or memorable names and could not be used. Several North American area codes were split to enable reuse of numbers. However, as the growth accelerated, the Bell System decided to switch to all-number calling (ANC) and to deprecate the use of exchange names. This extended the usable numbering plan and only two area code splits became necessary between 1962 and 1981. All-number calling was phased in slowly starting in 1958. Most areas had adopted it fully by the late 1960s, though it did not become universal until the 1980s. The Bell System published and distributed area code handbooks yearly which compiled the towns available for calling using an area code.
The transition was slow in its implementation, taking the better part of the 1970s and even into the early 1980s to complete. Thus, telephone exchange names were still in use with telephone numbers well after the introduction of area codes.
AT&T employed a gradual strategy to ease the transition for customers. Originally, directory listings were printed with the exchange names spelled out in full, e.g.,
- Jones John 123 Anystreet............BUtterfield 5-1212
- Jones John Paul 5 Revolution Rd......ANdrew 3-2368
First stage was to print only the dialed letters:
- Jones John 123 Anystreet....................BU 5-1212
- Jones John Paul 5 Revolution Rd..........AN 3-2368
Second stage was to assign a selected letters combination in communities being converted from five- or fewer dialed digits to seven; no name was associated with the letters:
- Ramsay Betty 12 Connecticut Rd...........LT 1-5225
Third stage was to assign ANC to smaller communities converting to seven-digit numbers.
- Appleby Charles 1210 MacGill Lane.........553-0086
AT&T proceeded to convert existing named exchanges to all-number calling, starting in smaller communities. No significant opposition arose until conversion began in major cities. In some cities such as San Francisco, opposition was organized; the opposition group in San Francisco was called the Anti Digit Dialing League, of which S. I. Hayakawa was a notable member. The opposition caused AT&T to slow down the conversion process, and names continued to be used in cities such as New York, which went to ANC only in 1978. Philadelphia had named exchanges in the Bell of Pennsylvania telephone book as late as 1983, long after AT&T had hoped to complete the conversion. A company in Philadelphia still letters its dump trucks with the DE 3 exchange as of 2009. Also, a company in Kansas City, Missouri still shows commercials using the WE Westport exchange in its phone number.
Bell Canada, Alberta Government Telephones, and B.C. Tel completed most conversions of existing numbers during the first half of the 1960s. Typically in larger communities, conversions would be timed with issues of the telephone directory.
For example, in London, Ontario, three conversions took place starting in February 1962 and completing in September 1963. GEneral 2, 3, and 9 were converted first; later GLadstone 1 and 5, and finally GEneral 4 and 8.
An example from Montreal, Quebec, on August 4, 1957:
- WIlbank became WEllington 2
- WEllington became WEllington 3 (a rare example of keeping the exchange name)
- FItzroy became WEllington 5
- GLenview became WEllington 7
- VEndome became DUpont 7
- HEmlock became POntiac 7
- TRenmore became POntiac 8
- HArbour became VIctor 5
- MArquette became VIctor 9
The use of letters in exchange names resulted in the placement of letters on the telephone dial, even outside the areas using the letter/number combinations. Some Canadian areas at first used original letter schemes (notably Calgary, Alberta) until later standardization within North America.
Two of the most notable cities using the first three letters, four digits system (3L-4N), with the 3L digits comprising the first three letters of the (local) exchange name were Paris and London. They are examples of the “big-city” problem, with a large city served by many manual exchanges, which could only be converted to automatic gradually, and necessitating operation with a mixture of manual and automatic exchanges for some years.
Telephone directories showed the first three letters of the exchange in bold caps if all seven digits were to be dialled; for example, a subscriber's number on London's Whitehall exchange was shown thus: "WHItehall 1212" (the number of Scotland Yard).
If the first three letters were in capitals but not bold capitals, e.g. HAYes 1295, the caller would dial the first three digits (the ABC digits) only, and when connected to Hayes ask the Hayes local operator for the local number (here 1295). Later call indicator working equipment was installed at some manual exchanges so that the caller could dial all seven digits, and the required number would be displayed to the local operator.
In the United Kingdom, the first Director exchange in London, Holborn Tandem, was cutover in 1927; preceded by any necessary changes in the London area, e.g. changing some exchange names and making all local numbers (4N) 4-digit. As each digit represents three letters the same network cannot have exchanges called BRIxton and CRIcklewood, which both correspond to 274. In smaller director areas some A-digit levels were combined so that local director exchange would only need four or less groups of directors instead of eight. But if (say) A-digit levels 7 and 8 were combined it would not be possible to have both PERivale and TERminus exchanges in the same network.
The other main UK conurbations followed suit, namely Manchester in 1930 (e.g., DEAnsgate 3414, the number for Kendals department store), Birmingham (in 1931), Glasgow (in 1937), and later Liverpool and Edinburgh (c1950).
The standards for converting exchange name letters in Europe varied, notably in the placement of the letters O, Q and Z.
The switchover to all figure dialling began in the UK in 1966 following the successful conversion of telephone numbers in Paris, in 1963, which until then had also used the 3L-4N combinations. For example, POMpadour became 706, LOUvre was 508, and PIGalle was replaced by 744.
In popular culture
At least four popular songs use old telephone exchanges in their names: "PEnnsylvania 6-5000" (PE 6-5000), recorded by Glenn Miller (the inspiration for that song, the Hotel Pennsylvania in New York City, still holds that phone number as of 2013, but it is now dialed as +1-212-736-5000); "BEechwood 4-5789", by The Marvelettes; "LOnesome 7-7203 by Hawkshaw Hawkins; and "ECho Valley 2-6809" by The Partridge Family. PEnnsylvania 6-5000 was later spoofed in the Bugs Bunny cartoon Transylvania 6-5000 and the horror/comedy film Transylvania 6-5000.
The title of BUtterfield 8, the 1935 John O'Hara novel whose film adaptation won Elizabeth Taylor an Academy Award for Best Actress, refers to the exchange of the characters' telephone numbers (on the Upper East Side of Manhattan).
Artie Shaw And His Gramercy 5 - Artie Shaw named his band the Gramercy Five after his home telephone exchange in Greenwich Village. In 1940 the original Gramercy Five pressed eight records, then dissolved this band in early 1941.
- A History of Engineering and Science in the Bell System: The Early Years (1875-1925) p578 by M. D. Fagen (editor) & Bell Labs technical staff (1975, Bell Telephone Laboratories)
- AT&T, Notes on Nationwide Dialing (1955)
- Bell System recommended exchange names (MIT source)
- "Customs: Give Me Liberty", TIME Magazine, 1962-07-13, retrieved 2009-11-22
- Common keypads. International and historical assignments of letters to numbers
- White, John. Artie Shaw. Continuum International Publishing Group, 2004. ISBN 0-8264-6915-9
- Privateline.com Telephone History: EXchange Names
- Telephone EXchange Name Project
- Official listing of Ma Bell's recommended names
- Old London Telephone Exchange Names
- Notes on Nationwide Dialing, AT&T - 1955. Section II Appendix A is a List of Suitable Central Office Names