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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.


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.


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.











This web page was last updated on: 13 December, 2008