page_title: Guglielmo Marconi
section_title: The British become interested
hierarchical_section_title: Guglielmo Marconi / Biography / Radio work / The British become interested
caption_attribution_description: English: British Post Office engineers inspect Guglielmo Marconi's wireless telegraphy (radio) equipment, during a demonstration on Flat Holm island, 13 May 1897. This was the world's first demonstration of the transmission of radio signals over open sea, between Lavernock Point and Flat Holm Island, a distance of 3 miles. In the background is the spark-gap transmitter, an induction coil (right) that generates high voltage pulses that create sparks between the balls of the Righi spark gap (left), which excites oscillating currents in a wire antenna suspended aloft by the pole seen in the center, ratiating radio waves. Information is transmitted by switching the transmitter on and off rapidly using a switch called a telegraph key (not visible), spelling out text messages in Morse code. In the foreground is the receiver. When receiving from the Lavernock station, the oscillating voltage from the antenna is applied to a coherer; a primitive radio wave detector consisting of a small tube containing two electrodes with metal filings between them. When a radio wave from a distant transmitter strikes the antenna and is applied to the coherer, the filings clump together and conduct electricity. A second circuit is attached to the coherer consisting of a battery which operates a relay (cylindrical objects at sides), which in turn sends a pulse of current to a Morse paper tape recorder (center). When a radio wave turns on the coherer, it sends a pulse to the recorder, which makes a mark on a paper tape. The Morse code message from the remote transmitter can be read from the tape, as the seated man is doing. The relays are contained within cylindrical metal shields to prevent their sparks from interfering with the sensitive coherer. Information from Retrospective:Radio waves across the water, TheFreeLibrary.com]
context_page_description: Guglielmo Giovanni Maria Marconi, 1st Marquis of Marconi FRSA was an Italian inventor and electrical engineer, known for his pioneering work on long-distance radio transmission, development of Marconi's law, and a radio telegraph system. He is credited as the inventor of radio, and he shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun "in recognition of their contributions to the development of wireless telegraphy".
  Marconi was also an entrepreneur, businessman, and founder of The Wireless Telegraph & Signal Company in the United Kingdom in 1897. He succeeded in making an engineering and commercial success of radio by innovating and building on the work of previous experimenters and physicists. In 1929, Marconi was ennobled as a Marchese by King Victor Emmanuel III of Italy, and, in 1931, he set up Vatican Radio for Pope Pius XI.
context_section_description: Marconi made the first demonstration of his system for the British government in July 1896. A further series of demonstrations for the British followed, and, by March 1897, Marconi had transmitted Morse code signals over a distance of about 6 kilometres (3.7 mi) across Salisbury Plain. On 13 May 1897, Marconi sent the first ever wireless communication over open sea – a message was transmitted over the Bristol Channel from Flat Holm Island to Lavernock Point near Cardiff, a distance of 6 kilometres (3.7 mi). The message read "Are you ready". The transmitting equipment was almost immediately relocated to Brean Down Fort on the Somerset coast, stretching the range to 16 kilometres (9.9 mi).
  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 Institution 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, Northern Ireland, was conducted on 6 July 1898. A transmission across the English channel was accomplished on 27 March 1899, from Wimereux, France to South Foreland Lighthouse, England.  Marconi set up an experimental base at the Haven Hotel, Sandbanks, Poole Harbour, Dorset, where he erected a 100-foot high mast.  He became friends with the van Raaltes, the owners of Brownsea Island in Poole Harbour, and his sailing boat, the Elettra, was often moored on Brownsea or at the Haven Hotel when he was not conducting experiments at sea.
  In December 1898, the British lightship service authorized the establishment of wireless communication between the South Foreland lighthouse at Dover and the East Goodwin lightship, twelve miles distant. On 17 March 1899, the East Goodwin lightship sent the first SOS message, a signal on behalf of the merchant vessel Elbe which had run aground on Goodwin Sands. The message was received by the radio operator of the South Foreland lighthouse, who summoned the aid of the Ramsgate lifeboat.
  In the autumn of 1899, the first demonstrations in the United States took place. Marconi had sailed to the U.S. at the invitation of the New York Herald newspaper to cover the America's Cup international yacht races off Sandy Hook, New Jersey. The transmission was done aboard the SS Ponce, a passenger ship of the Porto Rico Line. Marconi left for England on 8 November 1899 on the American Line's SS Saint Paul, and he and his assistants installed wireless equipment aboard during the voyage. On 15 November Saint Paul became the first ocean liner to report her imminent return to Great Britain by wireless when Marconi's Royal Needles Hotel radio station contacted her 66 nautical miles off the English coast.
caption: British Post Office engineers inspect Marconi's radio equipment during a demonstration on Flat Holm Island, 13 May 1897.  The transmitter is at centre, the coherer receiver below it, and the pole supporting the wire antenna is visible at top.
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