Guglielmo Marconi

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Guglielmo Marconi is generally characterized as the inventor of radio. For competing claims, see: History of radio, Invention of Radio.

Guglielmo Marchese Marconi, GCVO (25 April 1874-20 July 1937) was an Italian inventor, best known for his development of a practical radiotelegraph system, which served as the foundation for the establishment of numerous affiliated companies worldwide. He shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun, "in recognition of their contributions to the development of wireless telegraphy".

Birth and early years

Marconi was born near Bologna, Italy, the second son of Giuseppe Marconi, an Italian landowner, and his Irish wife, Annie Jameson, granddaughter of the founder of the Jameson Whiskey distillery. He had a brother Alfonso and a stepbrother Luigi. Marconi was educated in Bologna, Florence and, later, in Livorno. Baptized as a Catholic, he was brought up Protestant by his mother and was a member of the Anglican church. He formally converted to Catholicism after his second marriage.

Radio work

Growing up, Marconi had an intense interest in science, and was especially fascinated by electricity. One of the more important scientific developments during this era came from Heinrich Hertz, who, beginning in 1888, became the first person to demonstrate devices that could produce and detect electromagnetic radiation—now known as "radio waves", at the time more commonly called "Hertzian waves". Hertz's death in 1894 brought published reviews of his earlier discoveries, and a renewed interest on the part of Marconi. He was permitted to briefly study the subject under Augusto Righi, a University of Bologna physicist who had done research on Hertz's work.

Marconi began to conduct experiments, building much of his own equipment in the attic of his home at the Villa Griffone in Pontecchio, Italy. His goal became to find a way to use radio waves to create a practical system of "wireless telegraphy"—i.e. the transmission of telegraph messages without the need for the connecting wires used by the electric telegraph. (This was not a completely new idea—numerous investigators had been exploring various wireless telegraph technologies for over 50 years, but none had yet proven commercially successful). Marconi developed a system with the following main components:

  • A relatively simple spark-gap radio transmitter, which was closely modeled after one designed by Righi, which in turn was similar to what Hertz had used.
  • A telegraph key, used to operate the transmitter to send short and long pulses, corresponding to the dots-and-dashes of Morse code.
  • A coherer receiver, which was a modification of Edouard Branly's original device, with refinements that made it more sensitive and reliable.
  • A telegraph register, activated by the coherer, which recorded the transmitted Morse code dots-and-dashes onto a roll of paper tape.

Similar configurations using spark-gap transmitters plus coherer-receivers had been tried by other experimenters, but they had been unable to achieve transmission ranges of more than a few hundred metres. At first, Marconi could only signal over similarly limited distances. However, in the summer of 1895, he moved his experimentation outdoors. After increasing the length of the transmitter and receiver antennas, and arranging them vertically, he stumbled across the fact that when one end of each antenna was allowed to touch the ground, the transmission range increased significantly. (Although Marconi did not understand the reason at the time, these "ground connections" allowed the earth to act as a waveguide for the surface wave signal.) Soon he was able to transmit signals, over the crest of a hill, to a distance of approximately 1.5 kilometres (1 mile). At this point he became convinced that, with additional funding and research, his devices would become capable of spanning even greater distances, and thus would prove valuable both commercially and for military use.

Finding limited interest in his work in his native Italy, in early 1896, at the age of 21, Marconi traveled to London, England, accompanied by his mother. (Marconi spoke fluent English in addition to Italian.) While there, he gained the interest and support of William Preece, the Chief Electrical Engineer of the British Post Office. A series of demonstrations for the British government followed—by March, 1897, Marconi had transmitted Morse code signals over a distance of about 6 kilometres (4 miles) across the Salisbury Plain, and on 13 May 1897, spanned the Bristol Channel from Lavernock Point, South Wales to Brean Down, a distance of 14 kilometres (8.7 miles). Impressed by these and other demonstrations, Preece introduced Marconi's ongoing work to the general public at two important London lectures: "Telegraphy without Wires," at the Toynbee Hall on 11 December 1896; and "Signalling through Space without Wires," given to the Royal Institute on 4 June 1897.

Numerous additional demonstrations followed, and Marconi began to receive international attention. In July, 1897, he carried out a series of tests at La Spezia, in his home country, for the Italian government. A test for Lloyds between Ballycastle and Rathlin Island, Ireland, was conducted in May, 1898. The English channel was spanned on 27 March 1899, between Wimereux, France and South Foreland Lighthouse, England, and in the fall of 1899 the first demonstrations in the United States took place, with the reporting of the America's Cup international yacht races at New York.

Commercial development

Marconi and equipment, circa 1903

On 2 June 1896 Marconi filed a Provisional Specification with the British Patent Office for his work, followed by a Complete Specification on 2 March 1897. On 2 July 1897, he was awarded British Patent GB12039 for Improvements in transmitting electrical impulses and signals, and in apparatus therefor, which is sometimes recognised as the world's first patent in radio telecommunication. An offer by the British Post Office to purchase the rights to Marconi's work was declined, and on 20 July 1897, the London-based Wireless Telegraph and Signal Company, Ltd. was incorporated, with Marconi serving as a director and the company's Chief Engineer (In March, 1900, the company was renamed Marconi's Wireless Telegraph Company, Ltd).

Eventually numerous additional companies were established worldwide, including the Marconi Wireless Telegraph Company of America, Inc. on 8 November 1899 and The Marconi International Marine Communication Company, Ltd. on 25 April 1900, which outfitted ships internationally with Marconi equipment and operators (Passengers could send and receive wireless telegrams called "Marconigrams"). In November, 1897, Marconi's first permanent transmitting station was erected at The Needles, Alum Bay, Isle of Wight in the south of England, and the next year saw the opening of the world's first "wireless telegraph" factory in Hall Street, Chelmsford, England, employing around 50 people. With the formation of the operating company, Marconi hired numerous important associates, and over time became less involved in the technical side of the concern, although he did patent a magnetic receiver in 1902, and in the 1920s conducted extensive research in shortwave transmissions, aboard his personal yacht, Elettra.

The various Marconi companies lost money for a number of years while they were being established—publicity about the value of radio in saving lives after the sinking of the RMS Titanic in 1912, plus the ensuing regulations requiring radio transmitters on seagoing vessels, helped to make the ventures profitable. The Marconi companies quickly became dominant in the United Kingdom and its colonies, but faced significant competition from other companies, especially German-based Telefunken. In 1912, after absorbing the bankrupted United Wireless, American Marconi gained a near-monopoly position in the United States. However, responding to U.S. government pressure, on 20 November 1919 the American Marconi assets were sold to the General Electric Company, which used them to form the Radio Corporation of America, creating a formidable commercial competitor.

Transatlantic transmissions

A major advantage of radio is its ability to provide communication over water. Marconi quickly began to build high-powered stations on both sides of the Atlantic Ocean, in order to communicate with ships at sea (In 1904, a commercial service was established to transmit nightly news summaries to subscribing ocean-going ships, which could incorporate them into their on-board newspapers). At the same time, he was quietly investigating whether it was possible to signal completely across the Atlantic, in order to compete with the transatlantic telegraph cables.

Marconi watching associates raise kite antenna at St. John's, December, 1901

Marconi soon made the stunning announcement that on 12 December 1901, using a 122-metre (400-foot) kite-supported antenna for reception, he had personally received at Signal Hill in St John's, Newfoundland (now part of Canada), signals transmitted by the company's new high-power station at Poldhu, Cornwall. The distance between the two points was about 3,500 kilometres (2,100 miles). Although widely heralded as a great scientific advance, there was also some skepticism about this claim, in part because the signals had only been heard faintly and sporadically. In addition, there was no independent confirmation of the reported reception, and the transmission, which merely consisted of the three dots of the Morse code letter S sent repeatedly, came from a transmitter whose signals were difficult to differentiate from the noise made by atmospheric static discharges. (A detailed technical review of Marconi's early transatlantic work appears in John S. Belrose's 1995.)[1]

Feeling challenged by the doubters, Marconi prepared a better organized and documented test. In February, 1902, the S.S. Philadelphia sailed west from Great Britain with Marconi aboard, carefully recording signals sent daily from the Poldhu station. The test results produced coherer-tape reception up to 2,496 kilometres (1,551 miles), and audio reception up to 3,378 kilometres (2,099 miles). Interestingly, the maximum distances were achieved at night, and thus these tests were the first to show that, for mediumwave and longwave transmissions, radio signals travel much farther at night than during the day. During the daytime, signals had been received only up to about 1,125 kilometres (700 miles), which was less than half of the distance claimed earlier at Newfoundland, where the transmissions had also taken place during the day. Because of this, Marconi had not fully confirmed the Newfoundland claims, although he did successfully prove that radio signals could be sent for hundreds of kilometres, in spite of the fact that some scientists had believed they were essentially limited to line-of-sight distances.

On 17 December 1902, a transmission from the Marconi station in Glace Bay, Nova Scotia, Canada, became the first radio message to cross the Atlantic in an eastward direction. On 18 January 1903, a Marconi station built near Wellfleet, Massachusetts in 1901 sent a message of greetings from Theodore Roosevelt, the President of the United States, to King Edward VII of the United Kingdom, marking the first transatlantic radio transmission originating in the United States. However, consistent transatlantic signalling turned out to be very difficult to establish. A regular transatlantic radiotelegraph service was finally announced in 1907, but even after this the company struggled for many years to provide reliable communication.

Titanic disaster

There were two radio operators on-board the Titanic, who were not employed by the White Star Line, but instead were employees of the Marconi International Marine Communication Company. Following the sinking of the ocean liner, survivors were rescued by the Carpathia, which also had Marconi operators. When this ship docked in New York, Marconi went aboard with a reporter from the New York Times.[2] On 18 June 1912, Marconi gave evidence to the Court of Inquiry into the loss of the Titanic regarding the marine telegraphy's functions and the procedures for emergencies at sea.[3]

Patent disputes

As is true for all inventions, Marconi's work built upon the discoveries of numerous other scientists and experimenters. (For a more comprehensive review of these events, see invention of radio and history of radio.) His original "two-circuit" equipment, consisting of a simple spark-gap transmitter plus a coherer-receiver, was similar to what had been utilized by many other experimenters, and in particular with that employed by Oliver Lodge in a series of widely reported demonstrations in 1894. Marconi's main claim for novelty was that through his work he had been able to signal for much greater distances than anyone else had achieved when using the spark-gap and coherer combination. However, there was controversy whether this was a sufficient enough breakthrough to deserve patent protection, or if his devices were too close to the original ones developed by Hertz, Branley and Lodge to be patentable.

Moreover, while Marconi's initial demonstrations were groundbreaking for the time, his original equipment was severely limited by being essentially untuned, which greatly restricted the number of spark-gap radio transmitters which could operate simultaneously in a given geographical area without causing mutually disruptive interference. Marconi addressed this defect with a patent application for a much more sophisticated "four-circuit" design, which featured two tuned-circuits at both the transmitting and receiving antennas. This was issued as British patent number 7,777 on 26 April 1900. However, this patent came after significant earlier work had been done on electrical tuning by, among others, among others, Nikola Tesla, Lodge, Braun, and John Stone Stone. (As a defensive move, in 1911 the Marconi Company purchased the Lodge-Muirhead Syndicate, whose primary asset was Oliver Lodge's 1897 tuning patent.) Thus, the "four-sevens" patent, and its equivalents in other countries, was the subject of numerous legal challenges, with mixed rulings which varied by jurisdiction, from full validation of Marconi's tuning patent to complete nullification. For example, in 1911 Mr. Justice Parker of the British High Court of Justice upheld Marconi's "four-sevens" tuning patent, while in 1943 the United States Supreme Court overturned Marconi's corresponding U.S. patent. These proceedings made up only a part of a long series of legal struggles, as major corporations jostled for advantage in a new and important industry.

Continuing work

Over the years, the Marconi companies began to gain a reputation for being technically conservative, in particular by continuing to use relatively inefficient spark-transmitter technology, which could only be used for radiotelegraph operations, long after it was becoming apparent that the future of radio communication lay with continuous-wave transmissions, which were more efficient and could also be used to make audio transmissions. Somewhat belatedly, beginning in 1914 the company started to do significant work with continuous-wave equipment, after the introduction of the oscillating vacuum-tube (valve). In 1920, employing a vacuum-tube transmitter, the Chelmsford Marconi factory was the location for the first entertainment radio broadcasts transmitted in the United Kingdom—one of these featured Dame Nellie Melba. In 1922, regular entertainment broadcasts commenced from the Marconi Research Centre at Writtle near Chelmsford. When the British Broadcasting Company was formed in 1922, the Marconi company was a prominent participant.

Personal life, later years and death

On 16 March 1905, Marconi married Beatrice O'Brien, daughter of Edward Donough O'Brien, 14th Baron Inchiquin, Ireland. They had three daughters (one of whom lived only a few weeks), and a son. They divorced in 1924 and the marriage was annulled in 1927. On 15 June 1927, Marconi married Maria Cristina Bezzi-Scali—they would have a single daughter.

In 1914 Marconi was both made a Senatore in the Italian Senate, and appointed Honorary Knight Grand Cross of the Royal Victorian Order in the United Kingdom. During World War I, Italy joined the Allied side of the conflict, and Marconi was placed in charge of the Italian military's radio service. In 1924, he was made a marchese by King Victor Emmanuel III.

More controversially, Marconi joined the Italian Fascist party in 1923. In 1930, Italian dictator Benito Mussolini appointed him to be the President of the Accademia d'Italia, which also made Marconi a member of the Fascist Grand Council. In 1935, Italian forces occupied the African nation of Ethiopia, resulting in near universal condemnation of Italy. However, Marconi made numerous radio speeches supporting the unprovoked attack, becoming notorious enough in the process for the BBC to ban him from talking about the subject.

Following his death at age 63, Italy held a state funeral commemorating Marconi's life. And, as a tribute, radio stations throughout the world observed two minutes of silence.

Notes

  1. ↑ Fessenden and Marconi: Their Differing Technologies and Transatlantic Experiments During the First Decade of this Century
  2. ↑ John P. Eaton & Charles A. Haas Titanic - Triumph and Tragedy, A Chronicle in Words and Pictures. 1994
  3. ↑ Court of Inquiry Loss of the S.S. Titanic 1912

Further reading

Relatives and company publications
  • Marconi, Degna, My Father, Marconi, James Lorimer & Co, 1982. ISBN 0-919511-14-7
  • Marconi's Wireless Telegraph Company, Year book of wireless telegraphy and telephony, London : Published for the Marconi Press Agency Ltd., by the St. Catherine Press / Wireless Press. LCCN 14017875 sn 86035439
Other
  • Aitken, Hugh G. J., Syntony and Spark: The Origins of Radio, New York: John Wiley & Sons, 1976. ISBN 0-471-01816-3
  • Aitken, Hugh G. J., The Continuous Wave: Technology and American Radio, 1900-1932, Princeton, New Jersey: Princeton University Press, 1985. ISBN 0-691-08376-2.
  • Baker, W. J., A History of the Marconi Company, 1970.
  • Coe, Douglas and Kreigh Collins (ills), Marconi, pioneer of radio, New York, J. Messner, Inc., 1943. LCCN 43010048
  • Garratt, G. R. M., The early history of radio: from Faraday to Marconi, London, Institution of Electrical Engineers in association with the Science Museum, History of technology series, 1994. ISBN 0-85296-845-0 LCCN gb 94011611
  • Geddes, Keith, Guglielmo Marconi, 1874-1937, London : H.M.S.O., A Science Museum booklet, 1974. ISBN 0-11-290198-0 LCCN 75329825 (ed. Obtainable in the U.S.A. from Pendragon House Inc., Palo Alto, California.)
  • Hancock, Harry Edgar, Wireless at sea; the first fifty years: A history of the progress and development of marine wireless communications written to commemorate the jubilee of the Marconi International Marine Communication Company, Limited, Chelmsford, Eng., Marconi International Marine Communication Co., 1950. LCCN 51040529 /L
  • Jolly, W. P., Marconi, 1972.
  • Masini, Giancarlo, Guglielmo Marconi, Turin: Turinese typographical-publishing union, 1975. LCCN 77472455 (ed. Contains 32 tables outside of the text)
  • Weightman, Gavin, Signor Marconi's magic box: the most remarkable invention of the 19th century & the amateur inventor whose genius sparked a revolution, 1st Da Capo Press ed., Cambridge, MA : Da Capo Press, 2003. ISBN 0-306-81275-4

External links

General
Transatlantic "signals"
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