The History of the Telephone - Alexander Graham Bell
**Alexander Graham Bell and Elisha Gray raced to invent the telephone.
In the 1870s, two inventors, Elisha Gray
and Alexander Graham Bell, both independently designed devices that could
transmit speech electrically (the telephone). Both men rushed their respective
designs to the patent office within hours of each other. Bell patented
his telephone first. Gray and Bell entered into a famous legal battle over the
invention of the telephone, which Bell won.
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| This model of Bell's first telephone is a duplicate of the instrument through which speech sounds were first transmitted electrically (1875). |
Evolution of the Telegraph into the
Telephone
The telegraph
and telephone are both wire-based electrical systems, and Alexander GrahamBell's success with the telephone came as a direct result of his attempts to
improve the telegraph.
When Bell began experimenting with
electrical signals, the telegraph had been an established means of
communication for some 30 years. Although a highly successful system, the
telegraph, with its dot-and-dash Morse code, was basically limited to receiving
and sending one message at a time. Bell's extensive knowledge of the nature of
sound and his understanding of music enabled him to conjecture the possibility
of transmitting multiple messages over the same wire at the same time. Although
the idea of a multiple telegraph had been in existence for some time, Bell
offered his own musical or harmonic approach as a possible practical solution.
His "harmonic telegraph" was based on the principle that several
notes could be sent simultaneously along the same wire if the notes or signals
differed in pitch.
Talk with Electricity
By October 1874, Bell's research had
progressed to the extent that he could inform his future father-in-law, Boston
attorney Gardiner Greene Hubbard, about the possibility of a multiple
telegraph. Hubbard, who resented the absolute control then exerted by the
Western Union Telegraph Company, instantly saw the potential for breaking such
a monopoly and gave Bell the financial backing he needed.
Bell proceeded with his work on the
multiple telegraph, but he did not tell Hubbard that he and Thomas Watson, a
young electrician whose services he had enlisted, were also exploring an idea
that had occurred to him that summer - that of developing a device that would
transmit speech electrically.
While Alexander Graham Bell and
Thomas Watson worked on the harmonic telegraph at the insistent urging of
Hubbard and other backers, Bell nonetheless met in March 1875 with Joseph Henry,
the respected director of the Smithsonian Institution, who listened to Bell's
ideas for a telephone and offered encouraging words. Spurred on by Henry's
positive opinion, Bell and Watson continued their work. By June 1875 the goal
of creating a device that would transmit speech electrically was about to be realized.
They had proven that different tones would vary the strength of an electric
current in a wire. To achieve success, they, therefore, needed only to build a
working transmitter with a membrane capable of varying electronic currents and
a receiver that would reproduce these variations in audible frequencies.
First Sounds - Twang
On June 2, 1875, Bell while
experimenting with his technique called "harmonic telegraph"
discovered he could hear sound over a wire.
The sound was that of a twanging
clock spring.
Bell's greatest success was achieved
on March 10, 1876, which marked not only the birth of the telephone but the
death of the multiple telegraph as well. The communications potential contained
in his demonstration of being able to "talk with electricity" far
outweighed anything that simply increasing the capability of a dot-and-dash
system could imply.
First Voice - Mr. Watson ...
Bell's notebook entry of March 10,
1876, describes his successful experiment with the telephone. Speaking through
the instrument to his assistant, Thomas A. Watson, in the next room, Bell
utters these famous first words, "Mr. Watson -- come here -- I want to see
you."
Born on March 3, 1847, in Edinburgh,
Scotland, Alexander Graham Bell was the son and grandson of authorities in
elocution and the correction of speech.
Educated to pursue a career in the
same specialty, his knowledge of the nature of sound led him not only to teach
the deaf, but also to invent the telephone.
- More on the Life of Alexander Graham Bell
- Alexander Graham Bell Timeline
- Alexander Graham Bell - Biography
Other
Inventions
Bell's unceasing scientific
curiosity led to the invention of the photophone,
to significant commercial improvements in Thomas Edison's phonograph, and to
development of his own flying machine just six years after the Wright Brothers
launched their plane at Kitty Hawk. As President James Garfield lay dying of an
assassin's bullet in 1881, Bell hurriedly invented a metal detector
in an unsuccessful attempt to locate the fatal slug.
Continue > Spread of Public
Telephone Service
Service
Lines and Switchboards
In 1877, construction of the first
regular telephone line from Boston to Somerville, Massachusetts was completed.
By the end of 1880, there were 47,900 telephones in the United States. The
following year telephone service between Boston and Providence had been
established. Service between New York and Chicago started in 1892, and between
New York and Boston in 1894. Transcontinental service by overhead wire was not
inaugurated until 1915. The first switchboard was set up in Boston in 1877. On
January 17, 1882, Leroy Firman received the first patent for a telephone
switchboard.
Bell
Telephone
The first Bell telephone company
started in 1878. This is now known as the American Telephone and Telegraph
Company (AT&T), which was incorporated in 1885.
Erna Schneider Hoover began working
for Bell Labs in 1945, and in 1971 she patented the first computerized
telephone exchange.
The first regular telephone exchange
was established in New Haven in 1878. Early telephones were leased in pairs to
subscribers. The subscriber was required to put up his own line to connect with
another. In 1889, Almon B. Strowger a Kansas City undertaker, invented a switch
that could connect one line to any of 100 lines by using relays and sliders. This
switch became known as "The Strowger Switch" and was still in use in
some telephone offices well over 100 years later. Almon Strowger was issued a
patent on March 11, 1891 for the first automatic telephone exchange.
The first exchange using the Strowger
switch was opened in La Porte, Indiana in 1892 and initially subscribers had a
button on their telephone to produce the required number of pulses by tapping.
An associate of Strowgers' invented the rotary dial in 1896 which replaced the
button.
In 1943, Philadelphia was the last
major area to give up dual service (rotary and button).
Pay
Phones
In 1889, the first coin-operated
telephone or pay phone was patented William Gray of by Hartford, Connecticut.
Gray's pay phone was first installed and used in the Hartford Bank.
Continue
> Telephones Go Wireless
Touch-Tone
Phones
In 1941, the first touch-tone system
that used tones in the voice frequency range rather than pulses generated by
rotary dials was installed in Baltimore, MD.
Cordless
Phone
In the 1970s, the very first
cordless phones were introduced. In 1986, the Federal Communications Commission
or FCC granted the frequency range of 47-49 MHz for cordless phones. Granting a
greater frequency range allowed cordless phones to have less interference and need
less power to run.
In 1990, the FCC granted the frequency range of 900 MHz for
cordless phones.
In 1994, digital cordless phones and
in 1995, digital spread spectrum (DSS) were both respectively introduced. Both
developments were intended to increase the security of cordless phones and
decrease unwanted eavesdropping by enabling the phone conversation to be
digitally spreadout. In 1998, the FCC granted the frequency range of 2.4 GHz
for cordless phones and as of 2003 the upward range is now 5.8 gigahertz.
- How Cordless Telephones WorkHow cordless phones work and a brief history of cordless phones.
Cell
Phones
In 1947, research into cell phones
technology began with an examination of the limited mobile (car) phones of the
times. Scientists realized that by using small cells (range of service area)
with frequency reuse they might be able to increase the traffic capacity of
mobile phones substantially.
- History of Cellular or Mobile Phones
- PCS Technology: Digital Cellular Phones
- Phone-Card-Phone: Disposable Cell Phones
Continue
> Finding A Number
Telephone
Books
The first telephone book was
published in New Haven, by the New Haven District Telephone Company in February
1878. It was one page long and held fifty names - no numbers were listed as the
operator would connect you. The page was divided into four heading residential,
professional, miscellaneous, and essential service listings.
Yellow Pages
In 1886, Reuben H. Donnelly produced
the first Yellow Pages directory featuring business names and phone numbers,
categorized by the types of products and services provided.
911
The history of 911 or the American
emergency phone system.
Caller
ID
In 1982, a patent for Caller ID was
filed by Carolyn Doughty of Bell Labs.
Continue > Resources & How Phones Work
- Private Line's Telephone History A very well detailed and accurate website on the history of the telephone.
- The History of the Telephone An entire book written in 1910 on the history of the telephone up to that time.
- Understanding the Telephone Everyone knows what a telephone is, but how does it work?
- Invention of the Alexander Graham Bell Telephone Alexander Graham Bell's path to the invention of the Bell telephone.
- Telephone Instruments A look at how the instrument itself developed and changed.
- The History of Pagers In 1949, the very first telephone pager was patented by Al Gross
- The History of Answering Machines In 1898, Danish telephone engineer and inventor, Valdemar Poulsen, patented the telegraphone, an early prototype answering machine.
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