Wireless World Without Wires

BROAD SHEET 25th April to 1st October 2006 communicates the work of the Museum of the History of Science, Oxford. It is posted on the Museum’s website, sold in the shop, and distributed to members of the mailing list, see www.mhs.ox.ac.uk. £1.00 T e l e g r a p h y that the universe was filled with a distance had been extended to over Wireless World Without Wires. homogeneous, continuous, elastic eight miles. The system was now -Last night, at medium which transmitted heat, to be put in operation officially n 2004 the Marconi Collection was presented to the University M y d d l e t o n - h a l l , light, electricity, and other forms between Sark and the other Channel of Oxford by the Marconi Corporation. This large and of energy from Islands, and in a short Upper-street, Islington, Mr. Marconi unrivalled archive of objects and documents records the Mr. W.H. Preece one point of space time a telegraph office I work of Guglielmo Marconi and the wireless telegraph to another. This had produced would be opened there “ delivered a lecture on company he founded. The documents are kept in the medium was ether, an instrument and messages would be “Telegraphy without Wires.” The Bodleian Library and the objects in the Museum of proceeds of the lecture are to be not air; and the which he had received and transmitted the History of Science. This exhibition of material devoted to the funds of the Islington discovery of its no hesitation without the aid of any real existence was communicating wires. from the collection presents the first decades of Wesleyan Circuit. There was a large in describing attendance, and Mr. Watson Surr one of the greatest He believed that this the history of radio (or ‘wireless’), from Marconi’s occupied the chair. Among those scientific events as the most new system would in the pioneering experiments and demonstrations at the present on the platform was Mr. of the Victorian delicate electrical near future prove of great end of the 19th century to the beginning of public Marconi, the inventor of the new era. What ether instrument they commercial and naval radio broadcasting in the 1920s. system of telegraphy. The lecturer was they did not possessed. and military value. Even recapitulated the facts and details know. But this if it turned out that it was agency was utilized in the new impossible to communicate over very Wireless transformed the modern world. At first it of the discovery as recorded in The was a means of individual communication, for sending Times of Monday last. He had, he means of telegraphy. Mr. Marconi long distances, could they estimate said, spent 47 years of his life in had produced an instrument which the value of the system as a means telegraphic messages in Morse code without the need the study of electricity. Not a day he had no hesitation in describing of communication between ship and for connecting cables, hence the name ‘wire-less’. Two passed that he did not come across as the most delicate electrical ship, or ship and shore? decades later radio signals were also being ‘broadcast’. something new and interesting, but instrument they possessed. The Mr. Marconi briefly Radio was entering the home, bringing information and he ventured to say that the system distance to which signals could be addressed the audience. entertainment, and anyone could ‘listen in’. The commonly of telegraphy he was there to explain sent by Mr. Marconi’s system was used expression ‘listening in’ perfectly captured the shift from was the greatest and most important remarkable. On Salisbury Plain a private and individual communication to public broadcasting distance of four miles had been discovery that had yet been made in accessible to everyone. this branch of science. They knew covered. In the Bristol Channel the The Times, Friday ”11 June 1897 The parabolic transmitter and receiver used by Marconi for his demonstration on Salisbury Plain in 1896. arconi began his research on radio Mwaves while at home in Bologna, inspired by the possibilities he saw in the n the final years of the 19th century work of early pioneers such as Heinrich IMarconi worked to extend the range Coherer Receiver, by Guglielmo of his radio signals and to demonstrate Hertz, Augusto Righi and Oliver Lodge. He Marconi, 1896. A coherer was linked Tuned Transmitter, by Marconi’s brought his vision and his enthusiasm to to a device such as a recorder or a their practical value. He established Tuned Transmitter, by Guglielmo Marconi, Wireless Telegraph Co. Ltd., c.1900. England in 1896, in search of support and bell to register the signal and to a stations on the south coast and the 1899. Marconi’s first tuned transmitter, com- A commercial version of the ‘tapper’. A mechanical tap to the pleted at the Haven Hotel, Poole. The square experimental tuned transmitter. commercial application, and in the same Isle of Wight, successfully exchanged wooden frame carries two windings, one coherer released its metal filings, signals with ships at sea and in March year applied for a patent for a system of making it non-conductive and ready to linked to the Leyden jar and the brass balls wireless telegraphy. receive the next signal. This example 1899 transmitted the first wireless that form a spark-gap. The single turn of the was used by Marconi in his famous message across the English Channel. He second winding was connected between an aerial and earth. Having demonstrated his system to the public demonstration of wireless in had not neglected the commercial side, Navy, Army and representatives of the London’s Toynbee Hall in 1896. establishing a factory in Chelmsford in Post Office in trials on Salisbury Plain, December 1898. Marconi arranged a demonstration to accompany a public lecture on telegraphy Once he went beyond simple by William Preece, chief engineer to Righi Oscillator or Spark-Gap, 1895. demonstrations of radio transmission the General Post Office. This was held An instrument for generating radio and reception, Marconi had to tackle the waves invented by Augusto Righi problem of interference between signals. in Toynbee Hall, the educational and of Bologna, who was influential charitable institution in London’s East in directing Marconi’s scientific The answer was ‘tuning’ – the ability to End, in December 1896. Preece operated interests. In 1896 Marconi brought transmit waves of a particular frequency the transmitter and whenever he created this example to England, where he and to adjust the receiver to accept one used it in demonstrations for the frequency at a time. an electric spark, a bell rang on a box Post Office. Marconi took to any part of the lecture In June 1898, Lord Kelvin visited Marconi room. There was no visible connection Morse Key, c.1900. This key was used by on the Isle of Wight and insisted on paying between the two. The demonstration Marconi during his experiments on tuned for the sending of messages by wireless circuits at the Haven Hotel, Poole in telegraphy and onward by cable, thus caused a sensation and made Marconi a c.1900. It was the first type of key designed challenging the General Post Office’s celebrity. specifically for wireless work. monopoly on telegraphy. Here he records the ‘ether’ or wireless message he sent. Experimental Valve, by J.A. Fleming, c.1889. This appears to be one of some 14 valves Fleming used for his experiments on the Edison effect in 1889-90. arconi’s most audacious December and, although the Kite, by G.C. Spencer & Telephone Receiver, by Collier- early ambition was to send balloons failed and one of the kites Sons, Balloon Makers, Hol- Marr Telephone & Electrical M loway, London, c.1901. One Manufacturing Co. Ltd., arconi’s method of a radio signal across the Atlantic. was blown away, after an anxious separating signals of the large linen kites, with Manchester, 1901. This was used M It was generally believed that wait they finally detected the pre- bamboo poles, Marconi to receive the first transatlantic through ‘tuning’ was the curvature of the earth made arranged signal from Poldhu. On and his assistants took to signal, the three dots of Morse granted a patent in April this impossible, because the 12 December they heard the three Newfoundland to raise the code for the letter ‘S’. After 1900 and by good fortune Draft, in Marconi’s hand, of the waves were expected to travel in dots – the letter ‘S’ in Morse – on aerial wires of his receiver struggling either to record or happened to be allocated specification for the patent at Signal Hill. recognise a signal, Marconi relating to tuning, 7777/1900. straight lines and could not pass a telephone wired in series with a famously handed this receiver a striking and memorable through the earth. sensitive detector. to his assistant with the words, number: 7777. This helped ‘Can you hear anything, Mr to establish the fame of Two wireless stations were The signal had been too weak Kemp?’ the ‘Four Sevens’ patent. set up in 1901: a transmitter to be printed on tape in the way of unprecedented power at telegraphic messages were usually Marconi had hired the Poldhu in Cornwall and a recorded, which led to problems in electrical engineer and receiving station at St John’s in convincing everyone that the trial Professor at University Newfoundland, where the aerial had succeeded. Two month’s later, College London, John was to be raised by a balloon or however, signals were successfully Ambrose Fleming.

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