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Guglielmo Marconi
1874 - 1937

The Italian inventor Guglielmo Marconi designed and constructed
the first wireless telegraph. For this work he received a Nobel
Prize.
The son
of a wealthy Italian father and an Irish mother, Guglielmo
Marconi was born April 25, 1874, in Bologna. He was educated by
private tutors and attended the Livorno (Leghorn) technical
institute for a short time.
In 1894 Marconi began experiments on electromagnetics near
Bologna. Leaving aside the fundamental nature of electromagnetic
waves, he directed his attention to the distance over which they
could be detected with the possibility in mind that they might
be used in a telegraph. He repeated Heinrich Hertz's experiments
and rapidly extended the range of detection. Moving out of doors
in 1895, he introduced a transmitter sparking between an
elevated aerial and earth. For detection he used a "coherer" (a
glass tube containing metal filings which becomes, and remains,
conducting when an electrical discharge passes through it but
which loses its conductivity following mechanical shock),
similarly connected between an aerial and earth. By the end of
1895 he was able to detect wireless signals at ranges greater
than a mile and out of the line of sight. By interrupting the
spark signal, he was able to transmit Morse code. Marconi
patented his invention in 1896.
Marconi was unable to interest the Italian government in
wireless, so in 1896 he went to England, where he aroused
official interest and received support from the British Post
Office. Ranges attained by his instrument rose quickly, to 8
miles and then 25 miles and more. In 1899 signals across the
English Channel, between Boulogne and Dover, caused a sensation,
though the distance was less than that covered by other
transmissions. In 1900 Marconi determined to try sending
wireless signals across the Atlantic, despite the theoretical
conflict between rectilinear propagation of Hertz radiation and
the curvature of the earth. He had, however, already received
signals at 250-mile range. Using the Poldhu transmitter, an
established station in southwestern England, and a temporary
aerial supported by a kite on Signal Hill, St. John's,
Newfoundland, nearly 1,800 miles away, he received the first
transatlantic wireless signals on Dec. 12, 1901.
Also in 1901 Marconi patented his "four-circuit" tuning system.
Thus multiplex wireless telegraphy became possible, and the
interference of one signal with another was minimized. In 1902
Marconi patented a sensitive magnetic radiodetector to replace
the coherer and, in 1905, the horizontal directional aerial,
which at once brought improvements in signal strengths and
allowed the development of long-distance commercial wireless.
After 1905 Marconi spent much of his time as an entrepreneur,
surrounded by a talented staff of engineers and administrators,
developing wireless telegraphy. Attempts to introduce a
transatlantic wireless press service in 1903 had been premature,
but in 1907 commercial communication was established between
Marconi stations at Clifden in western Ireland and Glace Bay,
Nova Scotia.
During World War I Marconi began experiments on shortwave radio
and on aerials designed to transmit along narrow beams to
minimize detection by an enemy. The year 1917 saw him as a
member of the Italian mission to the United States on its entry
into the war, and in 1919 he was a signatory to the Paris Treaty
for Italy. He spent much of the next decade continuing the
shortwave investigations begun in wartime, making useful
discoveries, but none to compete with the great postwar
expansion of the radio networks consequent on the development of
radiotelephony and voice radio. He was hailed as the father of
radio, but, especially in the United States, the real progress
was made by a new generation.
Marconi died on July 20, 1937, in Rome of a heart attack. He was
a modest man of great scientific integrity, and his
uncorroborated word was perhaps more readily accepted than that
of any other inventor. He shared the 1909 Nobel Prize for
physics with K. F. Braun.
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The greatest strength of Guglielmo Marconi was not his ability
to innovate, but his mastery of synthesis. Assimilating the
ideas and inventions of others, Marconi brilliantly fashioned a
working technology. Born in Bologna, Italy, on April 25, 1874,
Marconi was the son of a wealthy Italian landowner and his
second wife. Educated by private tutors as a child, Marconi was
later sent to the Technical Institute in Leghorn, where he
studied physics and electromagnetism.
A number of key events set the stage for Marconi's experiments.
British physicist James Clerk Maxwell (1831-1879) had
established a theory about the existence and behaviour of
invisible electromagnetic radiation in the 1860s. About twenty
five years later, German physicist Heinrich Hertz successfully
generated such radiation, which he dubbed "Hertzian waves,"
using a spark-gap device. In 1894, English physicist Oliver
Lodge invented a "coherer " capable of detecting Hertzian waves
with relative efficiency, and a year later in Russia Aleksandr
Popov had devised an antenna circuit capable of boosting
reception and transmission.
In 1894, the year that Hertz died, Marconi came across a
technical magazine that discussed some of the possibilities of
Hertzian waves. Intrigued, he began to experiment with a
spark-gap generator at his family's estate. He made a key
improvement to the coherer, and devised an effective vertical
antenna consisting of an elevated metal plate connected to
another plate on the ground. Within a year, Marconi was
successful in sending wireless Morse code signals a distance of
more than 1.5 miles (2.4 km). Marconi also found that when he
attached sheets of metal to his antenna in certain
configurations, the radiated radio waves focused into a
directional beam. When Marconi was able to transmit and receive
over a hill that blocked the line of sight in September 1895,he
became convinced that the potential of radio as a means of
communication was far greater than anyone had anticipated.
Because the Italian government showed little interest in his
work, Marconi decided to move to London in 1896. Britain was the
naval power of the world, and he hoped to interest the British
navy in wireless communication. Assisted by Sir William Preece,
chief engineer of the British postal service, Marconi carried
out a series of demonstrations on land that covered distances of
up to nine miles (14.5 km), and generated an increasing amount
of attention.
Marconi demonstrated better business sense than many of his
contemporaries. Seeing the commercial potential of radio, he
began to protect the devices he used by taking out patents with
the help of his cousin, a British engineer. He received his
first patent for a radio transmitting apparatus on June 2, 1896.
Marconi also founded corporations both in Britain and the United
States, and continued to file important patents guaranteeing his
companies exclusive use of key devices.
Marconi continued to make improvements to his wireless system.
In 1899 he built a wireless station to communicate with one in
France, located 31 miles (50km) across the English Channel. He
also tested his system successfully on British and Italian naval
vessels. Was there any limit to how far the waves would travel?
Since radio waves, like light waves, seemed to move only in
straight lines, many experts felt that they would travel no
further than the distance to the horizon from an elevated
antenna, or two hundred miles (about 300 km). But on December
12, 1901, Marconi, proved such predictions wrong, and created a
major sensation when he successfully transmitted a signal 2,137
miles(3,440 km) across the Atlantic Ocean from Poldhu, Cornwall,
England to St. John's, Newfoundland, Canada. It was not
understood how this was accomplished until Arthur Kennelly
(1861-1939) and Oliver Heaviside (1850-1925) deduced that a
reflecting layer of charged particles in the upper atmosphere
had to be responsible. Radio waves evidently "bounced" off it
and back to earth, where they were received. This layer, called
the ionosphere, was proven to exist by Edward Appleton
(1892-1965) in 1924.
Marconi's demonstration that radio signals could cross vast
distances assured the future of radio as an important form of
communication. By 1902, regular messages were being send across
the Atlantic. In the subsequent years, Marconi helped to develop
radio as a viable industry with the companies he had
established, and in the process he created more important
devices, including a magnetic detector and a new directional
antenna. He also enlisted the help of scientists like John
Ambrose Fleming, whose invention of the vacuum tube further
cemented the position of radio as a practical technology.
Marconi explored the potential of shorter wavelengths for radio
communication into the 1930s. Once again, Marconi's intuition
proved sound, as it was found that such shortwave radio signals
could carry over tremendous distances using far less power than
the long waves originally used. Marconi shared the 1909 Nobel
Prize with Karl F. Braun for innovations in radio technology. He
died on July 20, 1937.
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Guglielmo Marconi was born at Bologna, Italy, on April 25, 1874,
the second son of Giuseppe Marconi, an Italian country
gentleman, and Annie Jameson, daughter of Andrew Jameson of
Daphne Castle in the County Wexford, Ireland. He was educated
privately at Bologna, Florence and Leghorn. Even as a boy he
took a keen interest in physical and electrical science and
studied the works of Maxwell, Hertz, Righi, Lodge and others. In
1895 he began laboratory experiments at his father's country
estate at Pontecchio where he succeeded in sending wireless
signals over a distance of one and a half miles.
In 1896 Marconi took his apparatus to England where he was
introduced to Mr. (later Sir) William Preece, Engineer-in-Chief
of the Post Office, and later that year was granted the world's
first patent for a system of wireless telegraphy. He
demonstrated his system successfully in London, on Salisbury
Plain and across the Bristol Channel, and in July 1897 formed
The Wireless Telegraph & Signal Company Limited (in 1900
re-named Marconi's Wireless Telegraph Company Limited). In the
same year he gave a demonstration to the Italian Government at
Spezia where wireless signals were sent over a distance of
twelve miles. In 1899 he established wireless communication
between France and England across the English Channel. He
erected permanent wireless stations at The Needles, Isle of
Wight, at Bournemouth and later at the Haven Hotel, Poole,
Dorset.
In 1900 he took out his famous patent No. 7777 for "tuned or
syntonic telegraphy" and, on an historic day in December 1901,
determined to prove that wireless waves were not affected by the
curvature of the Earth, he used his system for transmitting the
first wireless signals across the Atlantic between Poldhu,
Cornwall, and St. John's, Newfoundland, a distance of 2100
miles.
Between 1902 and 1912 he patented several new inventions. In
1902, during a voyage in the American liner "Philadelphia", he
first demonstrated "daylight effect" relative to wireless
communication and in the same year patented his magnetic
detector which then became the standard wireless receiver for
many years. In December 1902 he transmitted the first complete
messages to Poldhu from stations at Glace Bay, Nova Scotia, and
later Cape Cod, Massachusetts, these early tests culminating in
1907 in the opening of the first transatlantic commercial
service between Glace Bay and Clifden, Ireland, after the first
shorter-distance public service of wireless telegraphy had been
established between Bari in Italy and Avidari in Montenegro. In
1905 he patented his horizontal directional aerial and in 1912 a
"timed spark" system for generating continuous waves.
In 1914 he was commissioned in the Italian Army as a Lieutenant
being later promoted to Captain, and in 1916 transferred to the
Navy in the rank of Commander. He was a member of the Italian
Government mission to the United States in 1917 and in 1919 was
appointed Italian plenipotentiary delegate to the Paris Peace
Conference. He was awarded the Italian Military Medal in 1919 in
recognition of his war service.
During his war service in Italy he returned to his investigation
of short waves, which he had used in his first experiments.
After further tests by his collaborators in England, an
intensive series of trials was conducted in 1923 between
experimental installations at the Poldhu Station and in
Marconi's yacht "Elettra" cruising in the Atlantic and
Mediterranean, and this led to the establishment of the beam
system for long distance communication. Proposals to use this
system as a means of Imperial communications were accepted by
the British Government and the first beam station, linking
England and Canada, was opened in 1926, other stations being
added the following year.
In 1931 Marconi began research into the propagation
characteristics of still shorter waves, resulting in the opening
in 1932 of the world's first microwave radiotelephone link
between the Vatican City and the Pope's summer residence at
Castel Gandolfo. Two years later at Sestri Levante he
demonstrated his microwave radio beacon for ship navigation and
in 1935, again in Italy, gave a practical demonstration of the
principles of radar, the coming of which he had first foretold
in a lecture to the American Institute of Radio Engineers in New
York in 1922.
He has been the recipient of honorary doctorates of several
universities and many other international honours and awards,
among them the Nobel Prize for Physics, which in 1909 he shared
with Professor Karl Braun, the Albert Medal of the Royal Society
of Arts, the John Fritz Medal and the Kelvin Medal. He was
decorated by the Tsar of Russia with the Order of St. Anne, the
King of Italy created him Commander of the Order of St. Maurice
and St. Lazarus, and awarded him the Grand Cross of the Order of
the Crown of Italy in 1902. Marconi also received the freedom of
the City of Rome (1903), and was created Chevalier of the Civil
Order of Savoy in 1905. Many other distinctions of this kind
followed. In 1914 he was both created a Senatore in the Italian
Senate and appointed Honorary Knight Grand Cross of the Royal
Victorian Order in England. He received the hereditary title of
Marchese in 1929.
In 1905 he married the Hon. Beatrice O'Brien, daughter of the
14th Baron Inchiquin, the marriage being annulled in 1927, in
which year he married the Countess Bezzi-Scali of Rome. He had
one son and two daughters by his first and one daughter by his
second wife. His recreations were hunting, cycling and motoring.
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This web page was last updated on:
13 December, 2008
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