Subscriber trunk dialling
Subscriber trunk dialling is a telephone system allowing subscribers to dial trunk calls without operator assistance. The term was introduced when it first became possible for long-distance calls to be dialled directly, is now used where calls to any destination can be dialled; the term subscriber trunk dialling is used in the United Kingdom, the Republic of Ireland, Australia and South East Asia. The corresponding term in the North American Numbering Plan, e.g. in the United States and Canada, is direct distance dialing. The term was extended when, on 8 March 1963, subscribers in London were able to directly dial Paris using international direct dialling; the introduction in the UK of subscriber dialling of long distance calls removed the distinction that had existed between trunk and toll calls. This term however, is still prevalent in India to describe any national call made outside one's local unit. A "subscriber" is someone who subscribes to, i.e. rents, a telephone line and a "trunk call" is one made over a trunk line, i.e. a telephone line connecting two exchanges a long distance apart.
Now that all calls may be dialled direct, the term has fallen into disuse. When telephone systems were first introduced, subscribers called a telephone exchange and asked a human operator to connect the call to another subscriber on the same exchange, it became possible to dial numbers on the same exchange. When subscribers in one area became able to dial non-local subscribers, the term used for the innovation was subscriber trunk dialling. In the UK, STD started before 5 December 1958 when the Queen, in Bristol, publicized it by dialling Edinburgh – the farthest distance a call could be directly dialled; the STD system was completed in 1979. The system required that a new STD code, which could be dialled by subscribers, be allocated to each area. With the introduction of subscriber trunk dialling each city with a Director system was assigned a 3-digit code, in which the second digit corresponded to the first letter of the city name on the telephone dial, with the exception of London which had the two-digit code 01.
Codes were changed. 01 London 021 Birmingham 031 Edinburgh 041 Glasgow 051 Liverpool 061 Manchester Until 1992, calls to these cities from the Republic of Ireland required the following codes: 031 London 032 Birmingham 033 Edinburgh 034 Glasgow 035 Liverpool 036 ManchesterIn that year, this changed to dialling in the international format 0044, the 03 range was withdrawn from use. Trunk prefix Telephone numbers in the United Kingdom Telephone numbers in India Telephone numbers in Australia Telephone numbers in New Zealand List of country calling codes The archives of BT including archives of its predecessor organizations: information relating to the history of the telephone system in the UK. Archive news article from the BBC on the introduction of Subscriber Trunk Dialing BBC video of first call taking place
Boston
Boston is the capital and most populous city of the Commonwealth of Massachusetts in the United States. The city proper covers 48 square miles with an estimated population of 685,094 in 2017, making it the most populous city in New England. Boston is the seat of Suffolk County as well, although the county government was disbanded on July 1, 1999; the city is the economic and cultural anchor of a larger metropolitan area known as Greater Boston, a metropolitan statistical area home to a census-estimated 4.8 million people in 2016 and ranking as the tenth-largest such area in the country. As a combined statistical area, this wider commuting region is home to some 8.2 million people, making it the sixth-largest in the United States. Boston is one of the oldest cities in the United States, founded on the Shawmut Peninsula in 1630 by Puritan settlers from England, it was the scene of several key events of the American Revolution, such as the Boston Massacre, the Boston Tea Party, the Battle of Bunker Hill, the Siege of Boston.
Upon gaining U. S. independence from Great Britain, it continued to be an important port and manufacturing hub as well as a center for education and culture. The city has expanded beyond the original peninsula through land reclamation and municipal annexation, its rich history attracts many tourists, with Faneuil Hall alone drawing more than 20 million visitors per year. Boston's many firsts include the United States' first public park, first public or state school and first subway system; the Boston area's many colleges and universities make it an international center of higher education, including law, medicine and business, the city is considered to be a world leader in innovation and entrepreneurship, with nearly 2,000 startups. Boston's economic base includes finance and business services, information technology, government activities. Households in the city claim the highest average rate of philanthropy in the United States; the city has one of the highest costs of living in the United States as it has undergone gentrification, though it remains high on world livability rankings.
Boston's early European settlers had first called the area Trimountaine but renamed it Boston after Boston, England, the origin of several prominent colonists. The renaming on September 7, 1630, was by Puritan colonists from England who had moved over from Charlestown earlier that year in quest for fresh water, their settlement was limited to the Shawmut Peninsula, at that time surrounded by the Massachusetts Bay and Charles River and connected to the mainland by a narrow isthmus. The peninsula is thought to have been inhabited as early as 5000 BC. In 1629, the Massachusetts Bay Colony's first governor John Winthrop led the signing of the Cambridge Agreement, a key founding document of the city. Puritan ethics and their focus on education influenced its early history. Over the next 130 years, the city participated in four French and Indian Wars, until the British defeated the French and their Indian allies in North America. Boston was the largest town in British America until Philadelphia grew larger in the mid-18th century.
Boston's oceanfront location made it a lively port, the city engaged in shipping and fishing during its colonial days. However, Boston stagnated in the decades prior to the Revolution. By the mid-18th century, New York City and Philadelphia surpassed Boston in wealth. Boston encountered financial difficulties as other cities in New England grew rapidly. Many of the crucial events of the American Revolution occurred near Boston. Boston's penchant for mob action along with the colonists' growing distrust in Britain fostered a revolutionary spirit in the city; when the British government passed the Stamp Act in 1765, a Boston mob ravaged the homes of Andrew Oliver, the official tasked with enforcing the Act, Thomas Hutchinson the Lieutenant Governor of Massachusetts. The British sent two regiments to Boston in 1768 in an attempt to quell the angry colonists; this did not sit well with the colonists. In 1770, during the Boston Massacre, the army killed several people in response to a mob in Boston.
The colonists compelled the British to withdraw their troops. The event was publicized and fueled a revolutionary movement in America. In 1773, Britain passed the Tea Act. Many of the colonists saw the act as an attempt to force them to accept the taxes established by the Townshend Acts; the act prompted the Boston Tea Party, where a group of rebels threw an entire shipment of tea sent by the British East India Company into Boston Harbor. The Boston Tea Party was a key event leading up to the revolution, as the British government responded furiously with the Intolerable Acts, demanding compensation for the lost tea from the rebels; this led to the American Revolutionary War. The war began in the area surrounding Boston with the Battles of Concord. Boston itself was besieged for a year during the Siege of Boston, which began on April 19, 1775; the New England militia impeded the movement of the British Army. William Howe, 5th Viscount Howe the commander-in-chief of the British forces in North America, led the British army in the siege.
On June 17, the British captured the Charlestown peninsula in Boston, during the Battle of Bunker Hill. The British army outnumbered the militia stationed there, but it was a Py
Telephone exchange names
A telephone exchange name or central office name was a distinguishing and memorable name assigned to a central office. It identified the switching system; each central office served a maximum of 10,000 subscriber lines identified by the last four digits of the telephone number. Areas or cities with more subscribers were served by multiple central offices hosted in the same building; the leading letters of a central office name were used as the leading components of the telephone number representation, so that each telephone number in an area was unique. These letters were mapped to digits, indicated visibly on a dial telephone. Several systematic telephone numbering plans existed in various communities evolving over time as the subscriber base outgrew older numbering schemes. A used numbering plan was a system of using two letters from the central office name with four or five digits, designated as 2L-4N or 2L-5N, or 2–4 and 2–5 but some large cities selected plans with three letters. In 1917, W. G. Blauvelt of AT&T proposed a mapping system that displayed three letters each with the digits 2 through 9 on the dial.
Telephone directories or other telephone number displays, such as in advertising listed the telephone number showing the significant letters of the central office name in bold capital letters, followed by the digits that identified the subscriber line. On the number card of the telephone instrument, the name was shown in full, but only the significant letters to be dialed were capitalized, while the rest of the name was shown in lower case. Telephone exchange names were used in many countries, but were phased out for numeric systems by the 1960s. In the United States, the demand for telephone service outpaced the scalability of the alphanumeric system and after introduction of area codes for direct-distance dialing, all-number calling became necessary. Similar developments followed around the world, such as the British all-figure dialling. In the United States, the most-populous cities, such as New York City, Philadelphia and Chicago implemented dial service with telephone numbers consisting of three letters and four digits according to a system developed by W. G. Blauvelt of AT&T in 1917.
This system mapped the letter of the telephone number to the digits on the telephone dial. Most other major Canadian and US cities, such as Toronto and Atlanta, were converted from manual exchanges using four digits to a local 2L-4N numbering plan. For example, in Montréal, ATwater 1234 was dialed as six pulls on the dial to send the digit sequence 281234. Starting in the late 1940s, all local numbering plans were changed to the 2L-5N system to prepare for nationwide Direct Distance Dialing. For example, under this system, a well-known number in New York City was listed as PEnnsylvania 6-5000. In small towns with a single central office, local calls required dialing only four or five-digits at most, without using named exchanges. A toll call required the assistance of an operator, who asked for the name of the town and the local station number; some independent telephone companies, not part of the Bell System did not implement central office names. In 1915, newly developed panel switching systems were tested in the Mulberry and Waverly exchanges in Newark, New Jersey.
When the technology first appeared in the Mulberry exchange, subscribers had no dials on their telephones and the new system was transparent to them — they asked an operator to ring their called party as usual. However, the operator keyed the number into the panel equipment, instead of making cord connections manually; the panel switch was from the early 1920s through the 1930s, installed in large metropolitan areas in the Bell System. By the 1950s twenty cities were served by this type of office. 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 uniformly across the nation. By Bell System policy, customers never needed to be concerned about whether they were calling an automatic or a manual exchange; the 2L-5N system became the North American standard, as customer-dialed long distance service came into use in the 1950s. Several standard formats of telephone numbers, based on central office names, capitalized the leading letters that were dialed, for example: BALdwin 6828 is a typical urban North American 3L-4N example, used in only large cities before conversion to two-letter central office names.
MArket 7032 is a typical North American six-digit telephone number. This format was in use from the 1920s through the 1950s, was phased out by ca. 1960. ENglewood 3-1234 is an example of the 2L-5N format implemented continent-wide starting in the 1940s, in preparation for DDD. MUrray Hill 5-9975 is another example of the 2L-5N format, one of the Ricardos' numbers on I Love Lucy; the H in Hill, although not dialed, is still capitalized as the first letter of the second word. In print, such as on business cards or in advertisements, the full central office name was shown only by the two letters: TEmpleton 1-6400 would appear as TE 1-6400. If the central office was known by a name, but no letters were dialed, it was common to capitalize only the first letter of the central office, e.g. Main 600W or Fairmont 33; such numbers were assigned in manual offices, the name would be spoken by a subscriber when requesting a destination. These were geographically significant names, such as the town's name. In large cities with coexisting manual and dial areas, the numbering was standardized to one format.
For example, when the last ma
Punched card
A punched card or punch card is a piece of stiff paper that can be used to contain digital data represented by the presence or absence of holes in predefined positions. Digital data can be used for data processing applications or, in earlier examples, used to directly control automated machinery. Punched cards were used through much of the 20th century in the data processing industry, where specialized and complex unit record machines, organized into semiautomatic data processing systems, used punched cards for data input and storage. Many early digital computers used punched cards prepared using keypunch machines, as the primary medium for input of both computer programs and data. While punched cards are now obsolete as a storage medium, as of 2012, some voting machines still use punched cards to record votes. Basile Bouchon developed the control of a loom by punched holes in paper tape in 1725; the design was improved by his assistant Jean-Baptiste Falcon and Jacques Vaucanson Although these improvements controlled the patterns woven, they still required an assistant to operate the mechanism.
In 1804 Joseph Marie Jacquard demonstrated a mechanism to automate loom operation. A number of punched cards were linked into a chain of any length; each card held the instructions for selecting the shuttle for a single pass. It is considered an important step in the history of computing hardware. Semyon Korsakov was reputedly the first to propose punched cards in informatics for information store and search. Korsakov announced his new method and machines in September 1832. Charles Babbage proposed the use of "Number Cards", "pierced with certain holes and stand opposite levers connected with a set of figure wheels... advanced they push in those levers opposite to which there are no holes on the cards and thus transfer that number together with its sign" in his description of the Calculating Engine's Store. In 1881 Jules Carpentier developed a method of recording and playing back performances on a harmonium using punched cards; the system was called the Mélographe Répétiteur and “writes down ordinary music played on the keyboard dans la langage de Jacquard”, as holes punched in a series of cards.
By 1887 Carpentier had separated the mechanism into the Melograph which recorded the player's key presses and the Melotrope which played the music. At the end of the 1800s Herman Hollerith invented the recording of data on a medium that could be read by a machine. "After some initial trials with paper tape, he settled on punched cards...", developing punched card data processing technology for the 1890 US census. His tabulating machines read and summarized data stored on punched cards and they began use for government and commercial data processing; these electromechanical machines only counted holes, but by the 1920s they had units for carrying out basic arithmetic operations. Hollerith founded the Tabulating Machine Company, one of four companies that were amalgamated to form a fifth company, Computing-Tabulating-Recording Company renamed International Business Machines Corporation. Other companies entering the punched card business included The Tabulator Limited, Deutsche Hollerith-Maschinen Gesellschaft mbH, Powers Accounting Machine Company, Remington Rand, H.
W. Egli Bull; these companies, others and marketed a variety of punched cards and unit record machines for creating and tabulating punched cards after the development of electronic computers in the 1950s. Both IBM and Remington Rand tied punched card purchases to machine leases, a violation of the 1914 Clayton Antitrust Act. In 1932, the US government took both to court on this issue. Remington Rand settled quickly. IBM viewed its business as providing a service. IBM fought all the way to the Supreme Court and lost in 1936. IBM had 32 presses at work in Endicott, N. Y. printing and stacking five to 10 million punched cards every day." Punched cards were used as legal documents, such as U. S. Government checks and savings bonds. During WW II punched card equipment was used by the Allies in some of their efforts to decrypt Axis communications. See, for example, Central Bureau in Australia. At Bletchley Park in England, 2,000,000 punched cards were used each week for storing decrypted German messages.
Punched card technology developed into a powerful tool for business data-processing. By 1950 punched cards had become ubiquitous in government. "Do not fold, spindle or mutilate," a generalized version of the warning that appeared on some punched cards, became a motto for the post-World War II era. In 1955 IBM signed a consent decree requiring, amongst other things, that IBM would by 1962 have no more than one-half of the punched card manufacturing capacity in the United States. Tom Watson Jr.'s decision to sign this decree, where IBM saw the punched card provisions as the most significant point, completed the transfer of power to him from Thomas Watson, Sr. The UNITYPER introduced magnetic tape for data entry in the 1950s. During the 1960s, the punched card was replaced as the primary means for data storage by magnetic tape, as better, more capable computers became available. Mohawk Data Sciences introduced a magnetic tape encoder in 1965, a system marketed as a keypunch replacement, somewhat successful.
Punched cards were still c
Pittsburgh
Pittsburgh is a city in the Commonwealth of Pennsylvania in the United States, is the county seat of Allegheny County. As of 2018, a population of 308,144 lives within the city limits, making it the 63rd-largest city in the U. S; the metropolitan population of 2,362,453, is the largest in both the Ohio Valley and Appalachia, the second-largest in Pennsylvania, the 26th-largest in the U. S. Pittsburgh is located in the south west of the state, at the confluence of the Allegheny and Ohio rivers. Pittsburgh is known both as "the Steel City" for its more than 300 steel-related businesses and as the "City of Bridges" for its 446 bridges; the city features 30 skyscrapers, two inclined railways, a pre-revolutionary fortification and the Point State Park at the confluence of the rivers. The city developed as a vital link of the Atlantic coast and Midwest, as the mineral-rich Allegheny Mountains made the area coveted by the French and British empires, Whiskey Rebels, Civil War raiders. Aside from steel, Pittsburgh has led in manufacturing of aluminum, shipbuilding, foods, transportation, computing and electronics.
For part of the 20th century, Pittsburgh was behind only New York and Chicago in corporate headquarters employment. S. stockholders per capita. America's 1980s deindustrialization laid off area blue-collar workers and thousands of downtown white-collar workers when the longtime Pittsburgh-based world headquarters moved out; this heritage left the area with renowned museums, medical centers, research centers, a diverse cultural district. Today, Apple Inc. Bosch, Uber, Autodesk, Microsoft and IBM are among 1,600 technology firms generating $20.7 billion in annual Pittsburgh payrolls. The area has served as the long-time federal agency headquarters for cyber defense, software engineering, energy research and the nuclear navy; the area is home to 68 colleges and universities, including research and development leaders Carnegie Mellon University and the University of Pittsburgh. The nation's eighth-largest bank, eight Fortune 500 companies, six of the top 300 U. S. law firms make their global headquarters in the area, while RAND, BNY Mellon, FedEx, Bayer and NIOSH have regional bases that helped Pittsburgh become the sixth-best area for U.
S. job growth. In 2015, Pittsburgh was listed among the "eleven most livable cities in the world"; the region is a hub for Environmental Design and energy extraction. In 2019, Pittsburgh was deemed “Food City of the Year” by the San Francisco-based restaurant and hospitality consulting firm af&co. Many restaurants were mentioned favorable, among them were Superior Motors in Braddock, Driftwood Oven in Lawrenceville, Spork in Bloomfield, Fish nor Fowl in Garfield and Bitter Ends Garden & Luncheonette in Bloomfield. Pittsburgh was named in 1758 by General John Forbes, in honor of British statesman William Pitt, 1st Earl of Chatham; as Forbes was a Scot, he pronounced the name PITS-bər-ə. Pittsburgh was incorporated as a borough on April 22, 1794, with the following Act: "Be it enacted by the Pennsylvania State Senate and Pennsylvania House of Representatives of the Commonwealth of Pennsylvania... by the authority of the same, that the said town of Pittsburgh shall be... erected into a borough, which shall be called the borough of Pittsburgh for ever."
From 1891 to 1911, the city's name was federally recognized as "Pittsburg", though use of the final h was retained during this period by the city government and other local organizations. After a public campaign, the federal decision to drop the h was reversed; the area of the Ohio headwaters was long inhabited by the Shawnee and several other settled groups of Native Americans. The first known European to enter the region was the French explorer/trader Robert de La Salle from Quebec during his 1669 expedition down the Ohio River. European pioneers Dutch, followed in the early 18th century. Michael Bezallion was the first to describe the forks of the Ohio in a 1717 manuscript, that year European fur traders established area posts and settlements. In 1749, French soldiers from Quebec launched an expedition to the forks to unite Canada with French Louisiana via the rivers. During 1753–54, the British hastily built Fort Prince George before a larger French force drove them off; the French built Fort Duquesne based on LaSalle's 1669 claims.
The French and Indian War, the North American front of the Seven Years' War, began with the future Pittsburgh as its center. British General Edward Braddock was dispatched with Major George Washington as his aide to take Fort Duquesne; the British and colonial force were defeated at Braddock's Field. General John Forbes took the forks in 1758. Forbes began construction on Fort Pitt, named after William Pitt the Elder while the settlement was named "Pittsborough". During Pontiac's Rebellion, native tribes conducted a siege of Fort Pitt for two months until Colonel Henry Bouquet relieved it after the Battle of Bushy Run. Fort Pitt is notable as the site of an early use of smallpox for biological warfare. Lord Jeffery Amherst ordered blankets contaminated from smallpox victims to be distributed in 1763 to the tribes surrounding the fort; the disease spread into other areas, infected other tribes, killed hundreds of thousands. During this period, the powerful nations of the Iroquois Confederacy, based in New York, had maintained control of much of the Ohio Valley as hunting grounds by right of conquest after defeating other tribes.
By the terms of the 1768 Treaty of
Area code 312
Area code 312 is the telephone area code for downtown Chicago, which includes the Chicago Loop and its immediate environs. The plan area is surrounded by area code 773, which serves the rest of Chicago. Both area codes are overlaid with area code 872. 312 similar to area code 514 in Montreal and area code 210 in San Antonio. It is bounded by North Avenue on the north, Western Avenue on the west, 35th Street on the south, with Lake Michigan to the east. In terms of geographic area covered, 312 is one of the smallest area codes in the nation, encompassing only a few square miles. Area code 312 was assigned to one of the original 86 numbering plan areas created in 1947 for the North American Numbering Plan; as a result of Illinois' dense population in the north, the state was split between four NPAs, given that each NPA could only accommodate 500 central offices. Area code 312 served all of the Illinois side of the Chicago metropolitan area, except for portions of Grundy, Kankakee, McHenry, Will counties in the area code for the rest of northern Illinois, 815.
On November 11, 1989, the suburbs were assigned area code 312 was reduced to Chicago. The 1989 split was intended as a long-term solution to relieve exchanges in one of the largest toll-free calling zones in the nation. However, within only five years, 312 was on the verge of exhaustion once again due to the proliferation of cell phones and fax machines in the 1990s; as a solution, all of the city outside of the downtown area was split off as area code 773 on October 11, 1996, making Chicago one of the few cities in the nation to be split between multiple area codes, along with New York City and Los Angeles. Since November 7, 2009, both 312 and 773 have been overlaid by 872. With the implementation of 872 local calls in Chicago require 10-digit dialing, in addition to the prefix'1'; the first production #4ESS toll switch was installed in Chicago in January 1976. Goose Island Brewery brews an ale named "312 Urban Wheat Ale" and "312 Urban Pale Ale". A restaurant at the Kimpton Hotels operated Hotel Allegro, at LaSalle and Randolph Streets in the Loop, is named "312 Chicago".
The Chicago-based Christian rock group Resurrection Band released a song called "Area 312" on their 1982 album DMZ Portions of the film RoboCop 2 were filmed in the Chicago area. A telephone number written on an abandoned building is 555-7890; the Snoop Dogg song "That's That", contains the lyrics: "Girl if you in the 312, holla at a playa". The Ludacris song "Area Codes" has 312 as one of the 43 area codes mentioned; the music project Radio Flyer used as a track title. The Kanye West song "New God Flow," contains the lyrics: "What has the world come to, I'm from the 312, where cops don't come through, dreams don't come true." The Disney Channel show Shake It Up, starring Bella Thorne, as Cecelia Grace "CeCe" Jones, Zendaya, as Raquel "Rocky" Oprah Blue, mentions 312 as both Rocky and Cece's area code. A 1960s AT&T commercial promoted calling long distance with the jingle "3-1-2.. 3-1-2 That toddlin town, that toddlin town", this jingle playing upon "Chicago" a popular song written by Fred Fisher, cleverly taught the nation this Chicago area code.
The Chicago hacking conference, started in 2009, known as THOTCON derived its name from the area code. The first two letters of the word “three”, the first letter of “one”, the first letter of “two”. List of Illinois area codes List of North American Numbering Plan area codes Map of Illinois area codes at North American Numbering Plan Administration's website List of exchanges from AreaCodeDownload.com, 312 Area Code
Long-distance calling
In telecommunications, a long-distance call or trunk call is a telephone call made to a location outside a defined local calling area. Long-distance calls are charged a higher billing rate than local calls; the term is not synonymous with placing calls to another telephone area code. Long-distance calls are classified into two categories: national or domestic calls which connect two points within the same country, international calls which connect two points in different countries. Within the United States there is a further division into long distance calls within a single state and interstate calls, which are subject to different regulations. Not all interstate calls are long distance calls. Since 1984 there has been a distinction between intra-local access and transport area calls and those between different LATAs, whose boundaries are not state boundaries. Before direct distance dialing, all long distance calls were established by special switchboard operators in exchanges where calls within the local exchange were dialed directly.
Completion of long distance calls was time-consuming and costly as each call was handled by multiple operators in multiple cities. Recordkeeping was more complex, as the duration of every toll call had to be manually recorded for billing purposes. In many less-developed countries, such as Spain, Mexico and Egypt, calls were placed at a central office the caller went to, filled out a paper slip, sometimes paid in advance for the call, waited for it to be connected. In Spain these were known as locutorios "a place to talk". In towns too small to support a phone office, placing long distance calls was a sideline for some businesses with telephones, such as pharmacies. In some countries, such as Canada and the United States, long-distance rates were kept artificially high to subsidize unprofitable flat-rate local residential services. Intense competition between long-distance telephone companies narrowed these gaps in most developed nations in the late 20th century; the cost of international calls varies among countries.
The receiving country has total discretion in specifying what the caller should be charged for the cost of connecting the incoming international call with the destination customer anywhere in the receiving country. This has only a loose, in some cases no, relation to the actual cost; some less-developed countries, or their telephone company, use these fees as a revenue source. In 1892, AT&T built an interconnected long-distance telephone network, which reached from New York to Chicago, the technological limit for non-amplified wiring. Users did not use their own phone for such connections, but made an appointment to use a special long-distance telephone booth or "silence cabinet" equipped with 4-wire telephones and other advanced technology; the invention of loading coils extended the range to Denver in 1911, again reaching a technological limit. A major research venture and contest led to the development of the audion—originally invented by Lee De Forest and improved by others in the years between 1907 and 1914—which provided the means for telephone signals to reach from coast to coast.
Such transcontinental calling was made possible in 1914 but was not showcased until early 1915, as a promotion for the upcoming Panama–Pacific International Exposition in San Francisco in the spring of the same year. On January 25, 1915, Alexander Graham Bell ceremonially sent the first transcontinental telephone call from 15 Dey Street in New York City, received by his former assistant Thomas A. Watson at 333 Grant Avenue in San Francisco; this process involved five intermediary telephone operators and took 23 minutes to connect by manually patching in the route of the call. "On October 9, 1876, Alexander Graham Bell and Thomas A. Watson talked by telephone to each other over a two-mile wire stretched between Cambridge and Boston, it was the first wire conversation held. Yesterday afternoon the same two men talked by telephone to each other over a 3,400-mile wire between New York and San Francisco. Dr. Bell, the veteran inventor of the telephone, was in New York, Mr. Watson, his former associate, was on the other side of the continent.
They heard each other much more distinctly than they did in their first talk thirty-eight years ago." On November 10, 1951, the first direct dial long-distance telephone call in North America was placed from Mayor M. Leslie Denning of Englewood, New Jersey to Mayor Frank Osborne of Alameda, California via AT&T's Bell System; the ten digit call was connected automatically within 18 seconds. The first subscriber trunk dialling in the United Kingdom was deployed December 5, 1958 with Elizabeth II placing a call from Bristol to Edinburgh. International calling After World War II, priority was given by AT&T in the USA and the various PTT entities in Europe to automating switching on the toll networks in their respective countries. Thus, when TAT-1 was opened for service, it was connected to international gateway offices at White Plains, NY and London that were automated for domestic calls; these were designed to be able to automatically switch outward and inward international circuits as soon as common signalling standards could be negotiated.
However, at the outset, to set up an international call, multiple operators were required: one to originate the call and
This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C" (in support of MIL-STD-188).
This article incorporates 
