Telegraphy is the long-distance transmission of
written messages without physical transport of letters. It is a
compound term formed from the
Greek
words
tele (τηλε) = far and
graphein (γραφειν) = write.
Radiotelegraphy or
wireless telegraphy transmits
messages using
radio. Telegraphy includes
recent forms of
data transmission such as
fax,
email,
telephone networks and
computer networks in general.
Terminology
A
telegraph is a device for transmitting and
receiving messages over long distances, i.e., for telegraphy. The
word telegraph alone now generally refers to an
electrical telegraph. Wireless
telegraphy is also known as "CW", for
continuous wave (a carrier modulated by
on-off keying), as opposed to the earlier radio technique of using
a
spark gap.
A
telegraph message sent by an
electrical telegraph operator (or
telegrapher) using
Morse code, or a
printing telegraph operator using
plain text was known as a
telegram or
cablegram, often shortened to a
cable or
a
wire message. Later, a telegram sent by a
Telex network, a switched network of
teleprinters similar to a telephone
network, was known as a
Telex message.
Before long distance telephone services were readily available or
affordable, telegram services were very popular and the only way to
convey information speedily over very long distances. Telegrams
were often used to confirm business dealings and were commonly used
to create binding legal documents for business dealings.
A
wire picture or
wire photo was
a newspaper picture that was sent from a remote location by a
facsimile telegraph.
The
teleostereograph machine, a forerunner to the modern
electronic fax, was developed by AT&T's Bell Labs
in the 1920s; however the first commercial use of
image facsimile telegraph devices date back to the
1800s.
Optical telegraph
- Main articles: Semaphore line
(visual telegraphy using signal arms or shutters), Flag semaphore (using hand-held flags),
Signal lamp (visual naval
communications) and Heliograph (visual
communications using reflected sunlight)
The first telegraphs came in the form of
optical telegraphs, including the use of
smoke signals,
beacons or
reflected light,
which have existed since ancient times. A
semaphore network invented by
Claude Chappe operated in France from 1792
through 1846. It helped
Napoleon enough to
be widely imitated in Europe and the U.S. The
Prussian system was put into
effect in the 1830s. The last commercial semaphore link ceased
operation in Sweden in 1880.
Semaphores were able to convey information more precisely than
smoke signals and beacons, and consumed no fuel. Messages could be
sent at much greater speed than
post
riders and could serve entire regions. However, like beacons,
smoke and
reflected light signals they
were highly dependent on good weather and daylight to work
(practical
electrical
lighting was not available until about 1880). They required
operators and towers every 30 km (20 mi), and could only
accommodate about two words per minute. This was useful to
governments, but too expensive for most commercial uses other than
commodity price information.
Electric telegraphs were to reduce the
cost of sending a message thirtyfold compared to semaphores, and
could be utilized non-stop, 24 hours per day, independent of the
weather or daylight.
Elevated
locations where optical telegraphs were placed for maximum
visibility were renamed to Telegraph Hill, such as
Telegraph Hill,
San Francisco
, and Telegraph Hill in the PNC Bank Arts
Center
in New
Jersey
.
Electrical telegraphs
One very
early experiment in electrical telegraphy was an
electrochemical telegraph created by the German physician, anatomist and inventor Samuel Thomas von Sömmering
in 1809, based on an earlier, less robust design of 1804 by
Catalan
polymath and scientist
Francisco Salvá i
Campillo. Both their designs employed multiple wires (up
to 35) in order to visually represent most Latin letters and
numerals. Thus, messages could be conveyed electrically up to a few
kilometers (in von Sömmering's design), with each of the telegraph
receiver's wires immersed in a separate glass tube of acid. As an
electrical current was applied by the sender representing each
digit of a message, it would at the recipient's end electrolyse the
acid in its corresponding tube, releasing a stream of hydrogen
bubbles next to its associated letter or numeral. The telegraph
receiver's operator would visually observe the bubbles and could
then record the transmitted message, albeit at a very low
baud rate.
One of the earliest
electromagnetic telegraph designs
was created by
Baron Schilling in
1832.
Carl Friedrich Gauss and Wilhelm Weber built and first used for
regular communication the electromagnetic telegraph in
1833 in Göttingen
, connecting Göttingen Observatory and the Institute
of Physics, covering a distance of about 1 km . The setup
consisted of a coil which could be moved up and down over the end
of two magnetic steel bars. The resulting induction current was
transmitted through two wires to the receiver, consisting of a
galvanometer. The direction of the
current could be reversed by commuting the two wires in a special
switch. Therefore, Gauß and Weber chose to encode the alphabet in a
binary code, using positive current and negative as the two
states.
A replica
commissioned by Weber for the 1873 World Fair based on his
original designs is on display in the collection of historical
instruments in the Department of Physics at University of
Göttingen
.There are two versions of the first message
sent by Gauß and Weber: the more official one is based on a note in
Gauss's own handwriting stating that "Wissen vor meinen – Sein vor
scheinen" ("knowing before opining, being before seeming") was the
first message sent over the electromagnetic telegraph. The more
anecdotal version told in Göttingen observatory is that the first
message was sent to notify Weber that the observatory's servant was
on the way to the institute of physics, and just read "Michelmann
kömmt" ("Michelmann is on his way"), possibly as a test who would
arrive first.
The first
commercial electrical
telegraph was constructed by Sir William Fothergill Cooke and
Sir Charles Wheatstone and
entered use on the Great Western
Railway in Britain
. It ran for from Paddington station
to West
Drayton
and came into operation on 9 July 1839.
It was
patented in the United Kingdom
in 1837. In 1843 Scottish inventor
Alexander Bain invented a device
that could be considered the first
facsimile machine. He called his invention
a "recording telegraph". Bain's telegraph was able to transmit
images by electrical wires. In 1855 an Italian abbot,
Giovanni Caselli, also created an electric
telegraph that could transmit images. Caselli called his invention
"
Pantelegraph".
Pantelegraph was
successfully tested and approved for a telegraph line between
Paris
and Lyon
.
Morse telegraph

A Morse key
An
electrical telegraph was independently developed and patented in
the United
States
in 1837 by Samuel
F. B. Morse. His assistant,
Alfred Vail, developed the Morse code signaling
alphabet with Morse.
America's first
telegram was sent by Morse on 6 January 1838, across two miles
(3 km) of wire at Speedwell Ironworks
near Morristown, New Jersey
. The message read "A patient waiter is no
loser."
On 24 May 1844, he sent the message
"What hath God wrought"
(quoting Numbers 23:23) from the Old
Supreme Court Chamber in the Capitol
in Washington to the old
Mt.
Clare Depot
in Baltimore
. This message was chosen by Annie Ellsworth
of Lafayette, Indiana, the daughter of Patent Commissioner
Henry Leavitt Ellsworth. The
Morse/Vail telegraph was quickly deployed in the following two
decades; the overland telegraph connected the west coast of the
continent to the east coast by 24 October 1861, bringing an end to
the
Pony Express.

The famous telegram sent by Samuel
F.
Morse from the Capitol in Washington to Alfred Vail in
Baltimore in 1844: "What hath God wrought"
Oceanic telegraph cables
The first commercially successful
transatlantic telegraph cable
was successfully completed on 18 July 1866. Earlier transatlantic
submarine cables installations were
attempted in 1857, 1858 and 1865. The 1857 cable only operated
intermittently for a few days or weeks before it failed. The study
of underwater telegraph cables accelerated interest in mathematical
analysis of very long
transmission
lines. The telegraph lines from Britain to India were connected
in 1870 (those several companies combined to form the
Eastern
Telegraph Company in 1872).

Major telegraph lines in 1891
Australia was first linked to the rest of the world in October 1872
by a submarine telegraph cable at Darwin. This brought news
reportage from the rest of the world.
Further advancements in telegraph technology occurred in the early
1870s, when
Thomas Edison devised a
full duplex two-way telegraph and then
doubled its capacity with the invention of
quadruplex telegraphy in 1874. Edison
filed for a U.S. patent on the duplex telegraph on 1 September 1874
and received on 9 August 1892.
The telegraph across the Pacific was completed in 1902, finally
encircling the world.
Wireless telegraphy
Nikola Tesla and other scientists and
inventors showed the usefulness of
wireless telegraphy, radiotelegraphy, or
radio, beginning in the 1890s.
Alexander Stepanovich Popov
demonstrated to the public his
wireless
radio receiver, which was also used as a lightning
detector, on 7 May 1895. before a group of
reporters on a stormy August evening in 1895 he proudly
demonstrated his wireless receiver. It was attached to a long 30
foot pole that he held aloft to maximize the signal. When asked by
one of the reporters if it was a good idea to hold this metal rod
in the middle of a storm he replied that all was well. After being
struck (and nearly killed) by a bolt of lightning he proudly
announced to the world that his invention also served as a
'lightning detector'.
Albert Turpain sent and received his first
radio signal, using Morse code, in France
, up to 25
meters in 1895.
Guglielmo Marconi sent and received his
first radio signal in Italy
up to 6
kilometres in 1896. On 13 May 1897, Marconi, assisted by George
Kemp, a Cardiff
Post Office engineer, transmitted the first
wireless signals over water to Lavernock
(near Penarth
in Wales
) from
Flat
Holm
. Having failed to interest the Italian
government, the twenty-two year old inventor
brought his telegraphy system to Britain and met William Preece, a Welshman, who was a major
figure in the field and Chief Engineer of the General Post Office. A pair of
masts about high were erected, at Lavernock Point and on Flat Holm.
The receiving mast at Lavernock Point was a high pole topped with a
cylindrical cap of zinc connected to a detector with insulated
copper wire. At Flat Holm the sending equipment included a
Ruhmkorff coil with an eight-cell battery.
The first trial on 11 and 12 May failed but on the 13th the mast at
Lavernock was extended to and the signals, in Morse code, were
received clearly. The message sent was "ARE YOU READY"; the Morse
slip signed by Marconi and Kemp is now in the
National Museum of Wales.
In 1898 Popov accomplished successful experiments of wireless
communication between a naval base and a
battleship.
In 1900
the crew of the Russian coast defense ship General-Admiral Graf
Apraksin as well as stranded Finnish fishermen were saved in
the Gulf of
Finland
because of exchange of distress telegrams between
two radiostations, located at Hogland island
and inside a Russian naval
base in Kotka
. Both
stations of wireless telegraphy were built under Popov's
instructions.
In 1901,
Marconi radiotelegraphed the letter "S" across the Atlantic
Ocean
from his station in Poldhu, Cornwall
to St.
John's, Newfoundland
.
Radiotelegraphy proved effective for rescue work in sea
disasters by enabling effective communication
between ships and from ship to shore.
Telegraphic improvements
A continuing goal in telegraphy has been to reduce the cost per
message by reducing hand-work, or increasing the sending rate.
There were many experiments with moving pointers, and various
electrical encodings. However, most systems were too complicated
and unreliable. A successful expedient to increase the sending rate
was the development of
telegraphese.
Other research focused on the
multiplexing of telegraph connections. By
passing several simultaneous connections through an existing copper
wire, capacity could be upgraded without the laying of new cable, a
process which remained very costly. Several technologies were
developed like
Frequency-division
multiplexing. Long
submarine communications
cables became possible in segments with
vacuum
tube amplifiers between them.
With the invention of the
teletypewriter, telegraphic encoding became
fully automated. Early teletypewriters used the ITA-1
Baudot code, a five-bit code. This yielded only
thirty-two codes, so it was over-defined into two "shifts,"
"letters" and "figures". An explicit, unshared shift code prefaced
each set of letters and figures.
The airline industry remains one of the last users of teletype and
in a few situations still sends messages over the
SITA or
AFTN networks. For example,
The
British Airways operations
computer system (
FICO) still
used teletype to communicate with other airline computer systems.
The same goes for
PARS (Programmed Airline
Reservation System) and IPARS that used a similar shifted six-bit
Teletype code, because it requires only eight bits per character,
saving bandwidth and money. A teletype message is often much
smaller than the equivalent
EDIFACT or
XML message. In recent years as airlines have
had access to improved bandwidth in remote locations,
IATA standard
XML is replacing
Teletype as well as
EDI.

CN Telegraph and Cable office
The first electrical telegraph developed a standard signaling
system for telecommunications. The "mark" state was defined as the
powered state of the wire. In this way, it was immediately apparent
when the line itself failed. The moving pointer telegraphs started
the pointer's motion with a "start bit" that pulled the line to the
unpowered "space" state. In early Telex machines, the start bit
triggered a wheeled commutator run by a motor with a precise speed
(later, digital electronics). The commutator distributed the bits
from the line to a series of relays that would "capture" the bits.
A "stop bit" was then sent at the powered "mark state" to assure
that the commutator would have time to stop, and be ready for the
next character. The stop bit triggered the printing mechanism. Stop
bits initially lasted 1.42 baud times (later extended to two as
signaling rates increased), in order to give the mechanism time to
finish and stop vibrating. Hence an ITA-2
Murray code symbol took 1 start, 5 data, and
1.42 stop (total 7.42) baud times to transmit.
Telex
By 1935, message routing was the last great barrier to full
automation. Large telegraphy providers began to develop systems
that used
telephone-like rotary
dialing to connect teletypes. These machines were called
"Telex". Telex machines first performed rotary-telephone-style
pulse dialing for
circuit switching, and then sent data by
Baudot code. This "type A" Telex routing
functionally automated message routing.
The first
wide-coverage Telex network was implemented in Germany
during the 1930s as a network used to communicate
within the government.
At the rate of 45.45 (±0.5%)
baud — considered
speedy at the time — up to 25 telex channels could share a single
long-distance telephone channel by using
voice frequency
telegraphy multiplexing, making
telex the least expensive method of reliable long-distance
communication.
Canada-wide automatic teleprinter exchange service was introduced
by the
CPR Telegraph Company and
CN Telegraph in July 1957 (the two
companies, operated by rival
Canadian National Railway and
Canadian Pacific Railway
would join to form
CNCP
Telecommunications in 1967). This service supplemented the
existing international Telex service that was put in place in
November 1956. Canadian Telex customers could connect with nineteen
European countries in addition to eighteen Latin American, African,
and trans-Pacific countries.
The major exchanges were located in Montreal
(01), Toronto
(02), Winnipeg
(03).
In 1958, Western Union Telegraph Company started to build a Telex
network in the United States. This Telex network started as a
satellite exchange located in New York City and expanded to a
nationwide network. Western Union chose Siemens & Halske AG,
now Siemens AG, and ITT to supply the exchange equipment,
provisioned the exchange trunks via the Western Union national
microwave system and leased the exchange to customer site
facilities from the local telephone company. Teleprinter equipment
was originally provided by Siemens & Halske AG and later by
Teletype Corporation. Initial direct International Telex service
was offered by Western Union, via W.U. International, in the summer
of 1960 with limited service to London and Paris.
In 1962, the major exchanges were located in New York City (1),
Chicago (2), San Francisco (3), Kansas City (4) and Atlanta (5).
The Telex network expanded by adding the final parent exchanges
cities of Los Angeles (6), Dallas (7), Philadelphia (8) and Boston
(9) starting in 1966.
The Telex numbering plan, usually a six-digit number in the United
States, was based on the major exchange where the customer's Telex
machine terminated. For example, all Telex customers that
terminated in the New York City exchange were assigned a Telex
number that started with a first digit "1". Further, all Chicago
based customers had Telex numbers that started with a first digit
of "2". This numbering plan was maintained by Western Union as the
Telex exchanges proliferated to smaller cities in the United
States. The Western Union Telex network was built on three levels
of exchanges. The highest level was made up of the nine exchange
cities previously mentioned. Each of these cities had the dual
capability of terminating both Telex customer lines and setting up
trunk connections to multiple distant Telex exchanges. The second
level of exchanges, located in large cities such as Buffalo,
Cleveland, Miami, Newark, Pittsburgh and Seattle, were similar to
the highest level of exchanges in capability of terminating Telex
customer lines and setting up trunk connections. However, these
second level exchanges had a smaller customer line capacity and
only had trunk circuits to regional cities. The third level of
exchanges, located in small to medium sized cities, could terminate
Telex customer lines and had a single trunk group running to its
parent exchange.
Loop signaling was offered in two different configurations for
Western Union Telex in the United States. The first option,
sometimes called local or
loop service,
provided a 60 milliampere loop circuit from the exchange to the
customer teleprinter. The second option, sometimes called long
distance or polar was used when a 60 milliampere connection could
not be achieved, provided a ground return polar circuit using 35
milliamperes on separate send and receive wires. By the 1970s, and
under pressure from the Bell operating companies wanting to
modernize their cable plant and lower the adjacent circuit noise
that these Telex circuits sometimes caused, Western Union migrated
customers to a third option called F1F2. This F1F2 option replaced
the DC voltage of the local and long distance options with
modems at the
exchange and
subscriber ends of the Telex
circuit.
Western Union offered connections from Telex to the AT&T
Teletypewriter eXchange (TWX) system in May 1966 via its New York
Information Services Computer Center. These connections were
limited to those TWX machines that were equipped with automatic
answerback capability per CCITT standard.
In 1970,
Cuba
and Pakistan
were still running 45.5 baud type A Telex.
Telex is still widely used in some developing countries'
bureaucracies, probably because of its reliability and low cost.
The
UN asserted at one time that more
political entities were reliably available by Telex than by any
other single method.
Around 1960[?], some nations began to use the "figures" Baudot
codes to perform "Type B" Telex routing.
Telex grew around the world very rapidly. Long before automatic
telephony was available, most countries, even in central
Africa and
Asia, had at least a
few high-frequency (
shortwave) Telex
links. Often these radio links were first established by government
postal and telegraph services (PTTs). The most common radio
standard,
CCITT R.44 had error-corrected
retransmitting time-division multiplexing of radio channels. Most
impoverished PTTs operated their Telex-on-radio (TOR) channels
non-stop, to get the maximum value from them.
The cost of TOR equipment has continued to fall. Although initially
specialised equipment was required, many
amateur radio operators now operate TOR (also
known as
RTTY) with special software
and inexpensive hardware to adapt computer sound cards to
short-wave radios.
Modern "cablegrams" or "telegrams" actually operate over dedicated
Telex networks, using TOR whenever required.
Operation and applications
Telex messages are routed by addressing them to a Telex address,
e.g. "14910 ERIC S", where 14910 is the subscriber number, ERIC is
an abbreviation for the subscriber's name (in this case
Telefonaktiebolaget L.M. Ericsson in Sweden) and S is the country
code. Solutions also exist for the automatic routing of messages to
different Telex terminals within a subscriber organization, by
using different terminal identities, e.g. "+T148".
A major advantage of Telex is that the receipt of the message by
the recipient could be confirmed with a high degree of certainty by
the "answerback". At the beginning of the message, the sender would
transmit a WRU (Who aRe yoU) code, and the recipient machine would
automatically initiate a response which was usually encoded in a
rotating drum with pegs, much like a
music
box. The position of the pegs sent an unambiguous identifying
code to the sender, so the sender could verify connection to the
correct recipient. The WRU code would also be sent at the end of
the message, so a correct response would confirm that the
connection had remained unbroken during the message transmission.
This gave Telex a major advantage over less verifiable forms of
communications such as telephone and fax.
The usual method of operation was that the message would be
prepared off-line, using
paper tape. All
common Telex machines incorporated a 5-hole paper-tape punch and
reader. Once the paper tape had been prepared, the message could be
transmitted in minimum time. Telex billing was always by connected
duration, so minimizing the connected time saved money. However, it
was also possible to connect in "real time", where the sender and
the recipient could both type on the keyboard and these characters
would be immediately printed on the distant machine.
Telex could also be used as a rudimentary but functional carrier of
information from one IT system to another, in effect a primitive
forerunner of
Electronic
Data Interchange. The sending IT system would create an output
(e.g., an inventory list) on paper tape using a mutually agreed
format. The tape would be sent by Telex and collected on a
corresponding paper tape by the receiver and this tape could then
be read into the receiving IT system.
One use of Telex circuits, in use until the widescale adoption of
x.400 and
Internet
email, was to facilitate a message handling system, allowing local
email systems to exchange messages with other email and Telex
systems via a central routing operation, or switch. One of the
largest such switches was operated by
Royal Dutch Shell as recently as 1994,
permitting the exchange of messages between a number of IBM
Officevision,
Digital
Equipment Corporation All-In-One and
Microsoft Mail systems. In addition
to permitting email to be sent to Telex addresses, formal coding
conventions adopted in the composition of Telex messages enabled
automatic routing of Telexes to email recipients.
Teletypewriter eXchange
The Teletypewriter eXchange (TWX) was developed by the
Bell System in the United States and originally
ran at 45.45 baud or 60 words per minute, using five level
Baudot code. Bell later developed a second
generation of TWX called "four row" that ran at 110 baud, using
eight level
ASCII code. The Bell System
offered both "3-row" Baudot and "4-row" ASCII TWX service up to the
late 1970s.
TWX used the public switched telephone network. In addition to
having separate Area Codes (510, 610, 710 and 810) for the TWX
service, the TWX lines were also set up with a special Class of
Service to prevent connections to and from
POTS to TWX and vice
versa.
The code/speed conversion between "3-row" Baudot and "4-row" ASCII
TWX service was accomplished using a special Bell "10A/B board" via
a live operator. A TWX customer would place a call to the 10A/B
board operator for Baudot - ASCII calls, ASCII - Baudot calls and
also TWX Conference calls. The code / speed conversion was done by
a Western Electric unit that provided this capability. There were
multiple code / speed conversion units at each operator
position.
Western Union purchased the TWX system from AT&T in January
1969. The TWX system and the special area codes (510, 610, 710 and
810) continued right up to 1981 when Western Union completed the
conversion to the Western Union Telex II system. Any remaining
"3-row" Baudot customers were converted to Western Union Telex
service during the period 1979 to 1981.
The modem for this service was the Bell 101 dataset, which is the
direct ancestor of the Bell 103
modem that
launched computer
time-sharing. The 101
was revolutionary, because it ran on ordinary telephone subscriber
lines, allowing the Bell System to run TWX along with POTS on a
single public switched telephone network.
International Record Carriers
Bell's original consent agreement limited it to international dial
telephony. The
Western Union Telegraph
Company had given up its international telegraphic operation in a
1939 bid to monopolize U.S. telegraphy by taking over ITT's PTT
business. The result was a de-emphasis on Telex in the U.S. and a
"cat's cradle" of international Telex and telegraphy companies. The
Federal Communications Commission refered to these companies as
"International Record Carriers" (IRCs).
- Western Union Telegraph Company
developed a subsidiary named Western Union Cable System. This
company later was renamed as Western Union International (WUI) when
it was spun-off by Western Union as an independent company. WUI was
purchased by MCI Communications
in 1983 and operated as a subsidiary of MCI International.
- ITT's "World Communications" division (later known as ITT World
Communications) was amalgamated from many smaller companies:
"Federal Telegraph", "All American Cables and Radio", "Globe
Wireless", and the common carrier division of Mackay Marine. ITT
World Communications was purchased by Western Union in 1987.
- RCA Communications (later known as RCA Global Communications)
had specialized in global radiotelegraphic connections. In 1986 it
was purchased by MCI International.
- Before World War I, the Tropical Radiotelegraph Company (later
known as Tropical Radio Telecommunications, or TRT) put radio
telegraphs on ships for its owner, the United Fruit Company , to enable them
to deliver bananas to the best-paying markets. Communications
expanded to UFC's plantations, and were eventually provided to
local governments. TRT eventually became the national carrier for
many small Central American nations.
- The French Telegraph Cable Company (later known as FTC
Communications, or just FTCC), which was owned by French investors,
had always been in the U.S. It laid undersea cable from the U.S. to
France. It was formed by Monsieur Puyer-Quartier. International
telegrams routed via FTCC were routed using the telegraphic routing
ID "PQ", which are the initials of the founder of the company.
- Firestone
Rubber developed its own IRC, the "Trans-Liberia
Radiotelegraph Company". It operated shortwave from Akron, Ohio
to the rubber plantations in Liberia
. TL is still based in Akron.
Bell Telex users had to select which IRC to use, and then append
the necessary routing digits. The IRCs converted between TWX and
Western Union Telegraph Co.
standards.
Arrival of the Internet
- Main article: History of
the Internet. See also: E-mail
and ARPANET
Around 1965,
DARPA commissioned
a study of decentralized switching systems. Some of the ideas
developed in this study provided inspiration for the development of
the
ARPANET packet switching research network, which
later grew to become the public
Internet.
As the
PSTN became
a digital network,
T-carrier "synchronous"
networks became commonplace in the U.S. A T1 line has a "frame" of
193 bits that repeats 8000 times per second. The first bit, called
the "sync" bit, alternates between 1 and 0 to identify the start of
the frames. The rest of the frame provides 8 bits for each of 24
separate voice or data channels. Customarily, a T-1 link is sent
over a balanced twisted pair, isolated with transformers to prevent
current flow. Europeans adopted a similar system (E-1) of 32
channels (with one channel for frame synchronisation).
Later,
SONET and SDH
were adapted to combine carrier channels into groups that could be
sent over
optic fiber. The capacity of
an optic fiber is often extended with
wavelength division
multiplexing, rather than rerigging new fibre. Rigging several
fibres in the same structures as the first fibre is usually easy
and inexpensive, and many fibre installations include unused spare
"
dark fibre", "dark wavelengths", and
unused parts of the SONET frame, so-called "virtual
channels."
In 2002, the Internet was used by
Kevin
Warwick at the
University of
Reading to communicate neural signals, in purely electronic
form, telegraphically between the nervous systems of two humans,
potentially opening up a new form of communication combining the
Internet and telegraphy.
, the fastest well-defined communication channel used for telegraphy is the SONET standard OC-768, which sends about 40 gigabits per second.
The theoretical maximum capacity of an optic fiber is more than
10
12 bits (one
terabit or one
trillion bits) per second . In 2006, no existing encoding system
approached this theoretical limit, even with wavelength division
multiplexing.
Since the Internet operates over any digital transmission medium,
further evolution of telegraphic technology will be effectively
concealed from users.
As of 2007, the Internet carried the majority of telegraphic
messages in the form of e-mail .
E-mail displaces telegraphy
E-mail was first invented for
Multics in the late 1960s. At first, e-mail was
possible only between different accounts on the same computer
(typically a
mainframe).
UUCP allowed different computers to be connected to
allow e-mails to be relayed from computer to computer. With the
growth of the Internet, e-mail began to be possible between any two
computers with access to the Internet.
Various private networks like
UUNET (founded
1987),
the Well (1985), and
GEnie (1985) had e-mail from the 1970s, but
subscriptions were quite expensive for an individual, US$25 to
US$50 per month, just for e-mail. Internet use was then largely
limited to government, academia and other government contractors
until the net was opened to commercial use in the 1980s.
By the early 1990s,
modems made e-mail a
viable alternative to Telex systems in a business environment. But
individual e-mail accounts were not widely available until local
Internet service providers were in place, although demand grew
rapidly, as e-mail was seen as the Internet's
killer app. The broad user base created by the
demand for e-mail smoothed the way for the rapid acceptance of the
World Wide Web in the
mid-1990s.
On Monday, 12 July 1999, a final telegram was sent from the
National Liberty Ship Memorial, the
SS Jeremiah O'Brien, in San Francisco
Bay to President
Bill Clinton in the
White House. Officials of Globe Wireless reported that "The message
was 95 words, and it took six or eight minutes to copy it." They
then transmitted the message to the White House via e-mail. That
event was also used to mark the final commercial U.S. ship-to-shore
telegraph message transmitted from North America by Globe Wireless,
a company founded in 1911.
Sent from its wireless station at Half Moon
Bay, California
, the sign-off message was a repeat of Samuel
F. B. Morse's message 155 years earlier, "What hath God
wrought?"
Worldwide status of telegram services
Eircom, Ireland's largest telecommunication
company and former PTT, formally discontinued Telex services on 30
July 2002.Western Union announced the discontinuation of all of its
telegram services effective from 31 January 2006. Only 20,000
telegrams were sent in 2005, compared with 20 million in 1929.
According to Western Union, which still offers money transfer
services, its last telegram was sent Friday, 27 January 2006. The
company stated that this was its "final transition from a
communications company to a financial services company." Telegram
service in the United States and Canada is still available,
operated by
iTelegram and Globegram. Some
companies, like Swedish
TeliaSonera,
still deliver telegrams as
nostalgic
novelty items, rather than a primary means of communication.
In the Netherlands, the telegram service was sold by KPN to Unitel
Telegram Services in 2001
[5155]. On 9 February 2007, according to the online
edition of the Telegraaf newspaper, the Netherlands national
telecommunications company KPN pulled the plug on the last Telex
machine in the Netherlands after having operated a Telex network
since 1933. As their Telex service had only 200 remaining
customers, it was decided that it was no longer worthwhile to
continue to offer Telex within the Netherlands. It is, however,
still possible to send Telex messages to foreign customers through
the Internet. In Belgium, traditional telex operations ceased 28
February 2007. The Belgacom Telex services were replaced by
RealTelex, an internet based Telex alternative.
In Japan,
NTT
provides a telegram (
denpou) service that is today used
mainly for special occasions such as weddings, funerals,
graduations, etc. Local offices offer telegrams printed on special
decorated paper and envelopes.
In
New
Zealand
, while general public use telegrams have been
discontinued, a modern variant has arisen for businesses, mainly
utilities and the like, to send urgent confidential messages to
their customers, leveraging off the perception that these are
important messages. New Zealand
Post describes the service as "a cost effective debt collection
tool designed to help you to recover overdue money from your
customers. New Zealand Post Telegrams are delivered by a courier in
a Telegram branded envelope on Telegram branded paper. This has
proven to be an effective method to spur customers into immediate
action".
In the
United
Kingdom
, the international telegram service formerly
provided by British Telecom has been spun off as an independent
company which promotes the use of telegrams as a retro greeting
card or invitation.
In
Australia,
Australia Post's TELeGRAM service "combines
new age demands with old world charm to offer you a quick,
convenient way to send a message that matters." Messages can be
submitted online or by telephone, and can be printed on a range of
template designs. The printed telegrams are dispatched using
Express Post Mail Service or the Ordinary Mail Service. Orders
received before 15:00 are dispatched on the same day. The cost of
the service, being AUD4.50 for Ordinary and AUD8.50 for Express
Post Mail Services in comparison with AUD0.55 for an Australia-wide
postage fee, makes this service too expensive for day-to-day
communication.
In
Mexico
, the
telegram is still used as a low-cost communication service for
people who cannot afford or do not have the computer skills
required to send an e-mail.
In
Nepal
, the Telex service has been discontinued as of
January 1, 2009. Nepal Telecom states the reason for its
decision due to "availability of advanced technology in data
communication."
In Bahrain, Batelco still offers telegram services. They are
thought to be more formal than an email or a fax, but less so than
a letter. So should a death or anything of importance occur,
telegrams would be sent.
In Switzerland, UTS took over telegram services from the national
PTTs. Telegrams could still be sent to and from most countries,
also to those which are mentioned in this article.
Social implications
Prior to the
electrical
telegraph, all but very small amounts of information could be
moved only a few miles per hour, as fast as a human or animal could
travel. The telegraph freed communication from the constraints of
geography. It isolated the message (information) from the physical
movement of objects or the process.
Telegraphy allowed organizations to actively control physical
processes at a distance (for example: railroad signaling and
switching of rolling stock), multiplying the effectiveness and
functions of communication. "... Once space was, in the phrase
of the day, annihilated, once everyone was in the same place for
the purposes of trade, time as a new region of experience,
uncertainty, speculation, and exploration was opened up to the
forces of commerce."
Worldwide telegraphy changed the gathering of information for news
reporting. Since the same messages and information would now travel
far and wide, the telegraph demanded a language "stripped of the
local, the regional; and colloquial". Media language had to be
standardized, which led to the gradual disappearance of different
forms of speech and styles of
journalism
and storytelling. It is believed that objective journalism finds
its roots in the communicative strictures of the telegraph.
Names of periodicals
The word "Telegraph" still appears in the names of numerous
periodicals in various countries, a remnant of the long period when
Telegraphy was a major means for newspapers to obtain news
information (see
Telegraph ).
See also
References
- UK
Post Office Telegram - example of the paper used to send
telegrams
- US
Western Union Telegram - example of the paper used to receive
telegram
- Sample contract cancellation, itelegram.com
website
- Jones, R. Victor Samuel Thomas von Sömmering's "Space Multiplexed"
Electrochemical Telegraph (1808-10), Harvard University
website. Attributed to " Semaphore to Satellite" , International
Telecommunication Union, Geneva 1965. Retrieved 2009-05-01
- R.W. Pohl, Einführung in die Physik, Vol. 3, Göttingen
(Springer) 1924
- Hubbard, Geoffrey (1965) Cooke and Wheatstone and the
Invention of the Electric Telegraph, Routledge & Kegan
Paul, London p. 78
- Roswell, New Mexico was named after
Annie Ellsworth's future husband, Roswell Smith.
- Briggs, Asa and Burke, Peter: "A Social History of the Media:
From Gutenberg to the Internet," p110. Polity, Cambridge,
2005.
- Conley, David and Lamble, Stephen (2006) The Daily Miracle:
An introduction to Journalism,(Third Edition) Oxford
University Press, Australia pp. 305-307
- Briggs, Asa and Burke, Peter: "A Social History of the Media:
From Gutenberg to the Internet," p117. Polity, Cambridge,
2005.
- Hobbs, Allan G. Five-unit codes (1999) accessed
2007-12-20
- C.J. Colombo, “Telex in Canada”, Western Union Technical
Review, January 1958: 21
- Phillip R. Easterlin, “Telex in New York”, Western Union
Technical Review, April 1959: 47 figure 4
- Phillip R. Easterlin, "Telex in New York", Western Union
Technical Review, April 1959: 45
- Phillip R. Easterlin, "Telex in Private Wire Systems", Western
Union Technical Review, October 1960: 131
- James S. Chin and Jan J. Gomerman, "CSR4 Exchange", Western
Union Technical Review, July 1966: 142–149
- Fred W. Smith, "European Teleprinters", Western Union Technical
Review, October 1960: 172-174
- Fred W. Smith, "A New Line of Light-duty Teleprinters and ASR
Sets", Western Union Technical Review, January 1964: 18–31
- T.J. O’Sullivan, "TW 56 Concentrator", Western Union Technical
Review, July 1963: 111-112
- Phillip R. Easterlin, "Telex in the U.S.A.", Western Union
Technical Review, January 1962: 2-15
- Kenneth M. Jockers, "Planning Western Union Telex", Western
Union Technical Review, July 1966: 92-95
- Kenneth M. Jockers, "Planning Western Union Telex", Western
Union Technical Review, July 1966: 94 figure 2
- Sergio Wernikoff, "Information Services Computer Center",
Western Union Technical Review, July 1966: 130
- "WU to Buy AT&T TWX" |title=Western Union News Volume II,
No. 4, January 15, 1969
- Warwick,
K, Gasson,
M, Hutt, B, Goodhew, I, Kyberd, P, Schulzrinne, H and Wu, X: "Thought
Communication and Control: A First Step using Radiotelegraphy",
IEE Proceedings on Communications, 151(3), pp.185-189,
2004
-
http://telecomweb.com/databases/tarifica/tariffsonline/sample.pdf
Details of Eircom Services
- Western Union Telegrams
- "NPR: Western Union sends its last telegram" by
Robert Siegel, February 2 2006
- Telegram Passes Into History
- [1]
- TVNZ: Telegrams back in vogue
- New
Zealand Post: Telegrams
- Telegrams Online
- http://www.auspost.com.au/telegram/
-
http://www.telecomm.net.mx/telegraficos/telegrama_nacional.htm
- http://www.ntc.net.np/
- Carey, James (1989) Communication as Culture,
Routledge, New York and London, pp.204
- Wark, McKenzie (1997) "The Virtual Republic," Allen &
Unwin, St. Leonards.
- Carey, James (1989) Communication as Culture,
Routledge, New York and London, pp.201-30
- Carey, James (1989). Communication as Culture,
Routledge, New York and London, p.210
- Carey, James (1989) Communication as Culture,
Routledge, New York and London
Further reading
- Dargan, J., The Railway Telegraph, Australian Railway Historical Society
Bulletin, March, 1985 pp49–71
- Kieve, Jeffrey L. — The Electric Telegraph: a Social
and Economic History David and Charles (1973) ISBN
0-7153-5883-9
- Standard, Tom — The Victorian Internet Berkley
Trade, (1998) ISBN 0-425-17169-8
- Wilson, Geoffrey, The Old Telegraphs, Phillimore &
Co Ltd 1976 ISBN 0900592796
External links
- The
Porthcurno Telegraph Museum The biggest Telegraph station in
the world, now a museum
- History of the U.S. Telegraphic Industry from Economic
History.net
- Distant
Writing — The History of the Telegraph Companies in
Britain between 1838 and 1868
- Royal Engineers Museum — Telegraph
Services
- Anglo-American Telegraph Company, Ltd. Records, 1866 – 1947 Archives Center, National
Museum of American History, Smithsonian Institution.
- Western Union Telegraph Company Records,
1820–1995 Archives Center, National Museum of American History,
Smithsonian Institution.
- Early telegraphy and fax engineering, still operable in a
German computer museum
- "Telegram Falls Silent Stop Era Ends Stop", The
New York Times, February 6, 2006