Marconi, Guglielmo

views updated May 11 2018

MARCONI, GUGLIELMO

MARCONI, GUGLIELMO (1874–1937), Italian physicist and inventor.

Guglielmo Marconi was born in Bologna on 25 April 1874, son of an Italian father (Giuseppe, a wealthy landowner) and an Irish mother (Annie Jameson). Because of frequent family moves during the winter months, first to England and then to Tuscany, Marconi did not receive traditional schooling. As a boy, Marconi developed a great interest in electrical science, which he furthered with Vincenzo Rosa, his tutor in Leghorn in the early 1890s, the only "teacher" figure Marconi later recognized. In the laboratory set up in his father's home in the Bolognese countryside, Villa Griffone, Marconi dedicated his time to experiments and readings and soon developed the ambition to become an inventor. Even his very first technical projects reflect his interest in real technological applications and their commercial potential.

In 1894 Marconi started experimenting with electromagnetic waves (the subject of research in many European research labs at that time) with the aim of signaling across space without wires. Following much experimentation, he managed to send signals over a distance of 2 kilometers (1.2 miles), beyond a hill situated between the transmission equipment (to which Marconi had added a grounded vertical antenna) and the reception apparatus (characterized by an extremely sensitive coherer, a device designed to pick up radio signals). These first wireless telegraphy experiments, in 1895, marked the beginnings of radio communications.

With the aim of developing his promising invention, Marconi decided to move to England, a country with a great interest in improving communication networks and home to his mother's family who were a great help in making the right contacts when he arrived in London in February 1896. Marconi had his first patent drawn up by top legal experts in June 1896 and began collaborating with William H. Preece, the chief engineer of the General Post Office, but after a long list of contacts and demonstrations decided to found a private company. In July 1897 the Wireless Telegraph and Signal Company (later known as Marconi's Wireless Telegraph Company) was registered in London.

In his role as technical director of the company, Marconi recruited top-class collaborators (among whom John Ambrose Fleming stands out, the future inventor of the diode valve) who worked with him on two main projects, increasing transmission capabilities and solving interference problems between stations. This latter issue was resolved with the renowned British patent No. 7777 for "Improvements in Apparatus for Wireless Telegraphy" (granted in 1900 and followed by lasting litigation), which covered a syntonic tuning device that considerably improved the communicative capabilities of radio.

Marconi proved adept at deciding which demonstrations to carry out and in making sure his every success was publicized. For example, the first radio-telegraphic media-oriented transmissions had a great success, carried out at two yachting events: the Kingstown Regatta near Dublin (1898) and the America's Cup competition off Sandy Hook, New Jersey (1899).

Among the fundamental milestones gained in the "distance conquest" (Marconi's main goal) were the setup of communication between England and France (50 kilometers [31 miles] in 1899) and the first transatlantic transmission (between England and Newfoundland, over 3,000 kilometers [1,860 miles] in December 1901). This last project was a real challenge for the scientific understandings of that time and involved a considerable economic gamble. Its success earned Marconi a great deal of fame and, at the same time, a great deal of hostility from cable companies who felt threatened by the enormous developments made in radiotelegraphy, and from a number of skeptics (many of whom were from the scientific community itself). Marconi defended himself by continuing to produce positive results, even as early as 1902, first from experiments conducted during a transatlantic voyage aboard the Philadelphia, and then onboard the Italian naval warship Carlo Alberto. That same year, Marconi completed a new kind of magnetic detector, which then became the standard wireless receiver for many years, replacing the coherer. In December 1902 he transmitted the first complete messages to Poldhu (located in Cornwall, England) from stations at Glace Bay, Nova Scotia, and later Cape Cod, Massachusetts. The transatlantic project culminated in 1907 with the opening of the first transatlantic commercial service between Glace Bay and Clifden, Ireland. One of the invention's main applications was for seafaring safety, and it is a well-known fact that the Titanic (1912) was fatefully fitted with Marconi wireless communication equipment.

From the beginning of World War I, Marconi began investigation of shortwaves (which he had used in his very first experiments), setting up new research projects that were mainly carried out onboard the Elettra, the yacht Marconi purchased in 1919, and transformed into a floating laboratory. Important experiments in 1923 led him to the establishment of the new high-speed beam system for long-distance communication: agreement was reached in 1924 to adopt this system throughout the British Empire. In 1926 his company built the first beam station, linking England and Canada, followed by further stations in subsequent years.

In 1923 Marconi joined the Fascist Party, and this led him to be given various prestigious public offices: in 1928 he was named as the National Research Council president, and in 1930 he took over the presidency at the Royal Italian Academy. Just a few years later his relationship with the Fascist Party started to weaken: Marconi was certainly among those who tried to dissuade the pro-German and anti-Jewish tendencies within the party and was one of the supporters of an alliance with Britain.

In 1931, having set up a shortwave station for the Vatican, Marconi supervised the pope's first broadcast to Catholics worldwide. In this same period he started studying microwaves, research on which the majority of modern radio systems are still based in the early twenty-first century. In 1934, at sea, aboard the Elettra, he used this technique for blind navigation by radio beacon.

Marconi was invited by many countries worldwide to demonstrate developments in radio communications—projects for which he had become a living icon. Among the numerous international honors and awards given to Marconi were sixteen honoris causa degrees and the Nobel prize for physics, which he shared with Karl Ferdinand Braun in 1909.

Marconi died in Rome on 20 July 1937. The world commemorated his death with an exceptional event: all radio stations observed a two-minute silence, during which time the ether fell silent—just like it had been in the pre-Marconi era.

See alsoItaly; Physics; Science and Technology.

bibliography

Bussey, Gordon. Marconi's Atlantic Leap. Coventry, U.K., 2000.

Dunlap, Orrin E., Jr. Marconi: The Man and His Wireless. New York, 1937. Reprint, New York, 1971.

Jensen, Peter R. In Marconi's Footsteps, 1894 to 1920: Early Radio. Kenthurst, N.S.W., Australia, 1994.

Jolly, W. P. Marconi. New York, 1972.

Weightman, Gavin. Signor Marconi's Magic Box: The Most Remarkable Invention of the Nineteenth Century and the Amateur Inventor Whose Genius Sparked a Revolution. Cambridge, Mass., 2003.

Barbara Valotti

Marconi, Guglielmo

views updated Jun 08 2018

MARCONI, GUGLIELMO

(b. Bologna, Italy, 25 April 1874; d. Rome, Italy, 20 July 1937)

engineering, physics.

Marconi was the second son of Giuseppe Marconi, a wealthy landowner, and his second wife, Annie Jameson, the daughter of an Irish whiskey distiller. His limited formal education, of early private tutoring followed by several years at the Leghorn lyceum, included special instruction in physics. His first wife, Beatrice O’Brien, was of an aristocratic Irish family; his second, Maria Bezzi-Scali, belonged to the papal nobility. Marconi was always a devoted citizen of Italy, and frequently acted in an official capacity for his government. Chief among the many honors awarded him was the Nobel Prize for physics, which he shared with K. F. Braun in 1909.

Marconi seems to have first learned in 1894 of Hertz’s laboratory experiments with electromagnetic waves. He was immediately curious as to how far the waves might travel, and began to experiment, with the assistance of Prof. A. Righi of Bologna. His initial apparatus resembled Hertz’s in its use of a Ruhm-korff-coil spark gap oscillator and dipole antennas with parabolic reflectors, but it replaced Hertz’s sparkring detector with the coherer that had been employed earlier by Branly and Lodge. Marconi quickly discovered that increased transmission distance could be obtained with larger antennas, and his first important invention was the use of sizable elevated antenna structures and ground connections at both transmitter and receiver, in place of Hertz’s dipoles. With this change he achieved in 1895 a transmission distance of 1.5 miles (the length of the family estate), and at about the same time conceived of “wireless telegraph” communication through keying the transmitter in telegraph code.

Marconi was unable to interest the Italian government in the practical potentialities of his work, however. In February 1896 he moved to London, where one of his Irish cousins; Henry Jameson Davis, helped him prepare a patent application. Davis, also arranged demonstrations of the wireless telegraph for government officials and in 1897 helped to form and finance the Wireless Telegraph and Signal Co., Ltd., which in 1900 became Marconi’s Wrieless Telegraph Co., Ltd. By the latter year Marconi had experimentally increased his signaling distance to 150 miles, and had decided to attempt transatlantic transmission. A powerful transmitter was built at Poldhu, Cornwall, England, and a large receiving antenna placed on Cape cod, Massachusetts. When the latter blew down in 1901, Marconi, who was anxious to forestall any competitors, sailed for Newfoundland where, using a kiteborne antenna and Solari’s carbon-on-stell detector with a telephone receiver, on 12 December he received the first transatlantic wireless communication, the three code dots signifying the letter “S.” Already well known, Marconi, at twenty-seven, became world famous overnight.

From 1902 Marconi devoted more of his time to managing his companies, which by 1914 held a commanding position in British and American maritime radio service. (The Radio Corporation of America was formed in 1919, partly to acquire his United States interests.) Throughout his career Marconi was exceptionally fortune in his ability to attract highly qualified employees and consultants; among them J. A. Fleming, inventor of the thermionic diode; H. J. Round, who developed the triode as a radio frequency oscillator and amplifier independently of De Forest; R. M. Vyvyan, who installed many of the early spark stations; and C. S. Franklin, designer of directional antennas. It was Franklin who—drawing upon Marconi’s earlier notion of exploring the communication potentialities of shortwaves by employing dipole antennas with highly directional reflectors— in 1920 developed such dipole antennas into a beamed radio-telephone circuit between London and Birmingham, operating at 20 MHz. Following a series of discoveries (made by radio amateurs, among others) that indicated the feasibility of establishing a 10,000-mile shortwave communication network, operable by both day and night, Marconi’s company completed a globegirdling system of shortwave beam stations in 1927.

From 1921 on Marconi had used his steam yacht Elettra as home, laboratory, and mobile receiving station in propagation experiments. In 1932 he discovered that still higher frequency waves (microwaves) could be received at a point much farther below the optical horizon than had been predicted by any theory. This phenomenon was exploited in later “scatter propagation” circuits, which added new reliability to communications in arctic regions.

BIBLIOGRAPHY

I. Original Works. Papers by Marconi are “Wireless Telegraphy,” in proceedings of the Institution of Electrical Engineers,28 , (1899), 273; “Wireless Telegraphy,” in Proceedings of the Royal Institution of Great Britain,16 (1899– 1901), 247–256; “Syntonic Wireless Telegraphy,” in Royal Society of Arts. Journal,49 (1901), 505; “The progress of Electric Space Telegraphy,” in Proceedings of the Royal Institution of Great Britain,17 (1902–1904), 195–210; “A Note on the Effect of Daylight Upon the Propagation of Electromagnetic Impulses over Long Distances,” in Procedings of the Royal Society,70 (1902), 344; and “Address on Wireless Telegraphy to Annual Dinner,” in Transactions of the American Institute of Electrical Engineers,19 (1902), 93–121.

See also “Recent Advances in Wireless Telegraphy,” in Proceedings of the Royal Institution of Great Britain,18 (1905–1907), 31–45; “Transatlantic Wireless Telegraphy,” ibid., 19 (1908–1910), 107–130; “Radiotelegraphy,” ibid., 20 (1911–1913), 193–209; “Radio Telegraphy,” in Proceedings of the Institute of Radio Engineers, 10 (1922), 215–238; “Results Obtained Over Very Long Distances by Short Wave Directional Wireless Telegraphy, More Generally Referred to as the Beam System,” in Royal Society of Arts. Journal, 72 (1924), 607; “Radio Communication” in Proceedings of the Institute of Radio Engineers, 16 (1928), 40–69; and “Radio Communication by Means of Very Short Electric Waves,” in Proceedings of the Royal Institution of Great Britain,27 (1931–1933), 509–544.

II. Secondary Literature. Fro information on Mar coni’s life and work, see B. L. Jacot de Boinod and D. M. B. Collier, Marconi—Master of Space (London, 1935); Douglas Coe, Marconi, Pioneer of Radio (New York, 1943); O. E. Dunlap, Jr., Marconi, The Man and His Wireless (New York, 1937); Degna Marconi, My Father, Marconi (New York, 1962); and W. P. Jolly, Marconi (New York, 1972).

Robert A. Chipman

Marconi, Guglielmo

views updated May 18 2018

Marconi, Guglielmo

Italian Physicist
18741937

Known as the father of radio, Guglielmo Marconi was born April 25, 1874 in Bologna, Italy. He was the younger son of an Italian landowner, Giuseppe Marconi, and Anne Jameson, whose father was the founder of the Jameson Irish whiskey distillery. As a youngster, Marconi spent the winter months in England or Florence, Italy, with his mother, brother, and English relatives. Schooling for the Marconi brothers was divided between their mother, who taught them English and religion, and a tutor, who provided instruction in Italian and other subjects. Perhaps through teaching her sons, Anne Marconi became aware her son's intellectual abilities and his determination to solve problems on his own. She supported Marconi's efforts throughout her life. He began exploring the properties of electricity at a young age by reading scientific publications and duplicating and modifying experiments. This exploration continued throughout his life resulting in the foundational work he did in the field of wireless technology and telecommunications.

Marconi attended primary and secondary schools. He was not noted for his scholarship. Instead of attending university, arrangements were made for him to study with Vincenzo Rosa, a professor of electrophysics. These sessions introduced Marconi to the work of Heinrich Hertz, James Clerk Maxwell, Oliver Joseph Lodge, and others conducting experiments to explain electromagnetic waves. Marconi approached the field with the idea of using these waves for wireless communication. His greatest contribution was applying theoretical and basic discoveries to develop useful applications. To test his ideas, Marconi built the necessary equipment from materials around the estate. His experiments were conducted in a laboratory at his home. The first hurdle to overcome was increasing the distance that a wireless transmission could travel. Marconi achieved greater distances by increasing the range of the transmitters, by improving the sensitivity of the receivers, and by using antennas. His standard message for testing equipment became the three-dot Morse code for the letter "S."

Once his messages were traveling more than a mile across the family estate, it was time to seek funding from the Italian government. His request was denied. The next logical place to apply was England because wireless telegraphy would benefit the country's naval and maritime activities. Also, his English relatives could and would help. In 1896, at age twenty-two, Marconi set out for England. He first applied for an English patent, then met with Sir William Peerce, chief engineer of the English Postal and Telegraph Services. Recognizing the value and potential of Marconi's work, Peerce became an advocate and close friend. Ship-to-ship and ship-to-shore wireless telegraphy was operational the following year and Marconi founded his first company, Wireless Telegraph and Signal Company Limited.

The next hurdle to overcome was sending a message across the Atlantic Ocean. The widely held theory was that the curvature of the Earth made the transmission impossible. Marconi enlisted the expertise of John Fleming to solve the technical problems related to his continuing experiments to transmit across the Atlantic. The first transatlantic transmission from Cornwall, England, to Newfoundland, Canada, occurred in 1901 proving that the curvature of the Earth did not limit transmissions. He solved the problem of messages going to multiple receivers by using different transmission frequencies and setting the sender and receiver to the same frequency. Marconi continued exploring the possibilities of radio waves for uses beyond telecommunications and is credited with proposing the use of microwaves as a form of physical therapy.

Marconi's approach to patents and business was very conservative. When applying for patents or support for his work, he would explain the function of his invention or outline the improvements over previous methods but did not include a full disclosure of the design until a patent was granted. He followed the same procedures when demonstrating his equipment. This method protected his work from others and allowed him more fully to realize the monetary value of his systems. Many honors were bestowed on him, including the Nobel Prize for Physics in 1909, which he shared with Karl Ferdinand Braun who modified Marconi's transmitters to increase their range and usefulness. Marconi's business empire stretched across Europe and the United States, and one result of his international reputation was his appointment to represent Italy at the Paris Peace Conference after World War I. (Marconi had served in the Italian Army and Navy during World War I.) He continued being productive until a few years before his death from a heart condition. Marconi died in Rome on July 20, 1937.

see also Geographic Information Systems; Telecommunication; Wireless Technology.

Bertha Kugelman Morimoto

Bibliography

Masini, Giancarlo. Marconi. New York: Marsilio Publishers, 1995.

Marconi, Guglielmo

views updated May 23 2018

Marconi, Guglielmo (1874–1937) Italian physicist who developed radio. By 1897, he was able to demonstrate radio telegraphy over a distance of 19km (12mi). In 1899, he established radio communication between France and England. By 1901, radio transmissions were being received across the Atlantic Ocean. He received the 1909 Nobel Prize in physics.

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