For this unit about using primary sources, any one of many contents could have been chosen. Teachers should feel to use a content area that can make the lessons relevant to their students and their curriculum. I selected the sinking of Titanic because I felt that many students already had background information about this topic as well as an interest in it. There are many questions about this tragedy that can engage students: Was the design of the ship faulty? Why was there so much disparity in survival rates between first and third class passengers? Why did Californian , anchored nearby, fail to recognize distress signals? Why were some of the lifeboats, already inadequate for the number of passengers and crew, sent away less than full?
Because this unit is part of this seminar "Electronics in the Twentieth Century", I have chosen to focus on the role of wireless telegraphy and Titanic.
Background Information on Wireless Telegraphy
For centuries people tried to find ways to communicate messages over distances without having to carry them in person. What follows is a summary of the invention of wireless telegraphy. It is provided here for teachers to make available as a handout to those students who have an interest and want to understand the historical background of the role of the wireless telegraph.
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A Brief History of Wireless Telegraphy
Electromagnetic or Radio Waves
Radios, cell phones, pagers, garage door openers, space probes, model airplane navigation, animal tracking, walkie-talkies,and other communication devices all rely on the use of electromagnetic or radio waves. We are indebted to Michael Faraday, an English scientist, who combined his own understanding of light and heat waves, electricity, and magnetism in order to propose a theory that there was an additional form of invisible waves and called these "lines of force". James Clerk Maxwell's development of a series of mathematical equations in 1864 proved the existence of electromagnetic waves and that the waves were precise and moved at the speed of light, 186,000 miles per second. Next came a German scientist Heinrich Hertz who performed a series of experiments in 1887 that generated electromagnetic waves, confirming Faraday's theories of a half century earlier as well as proving the accuracy of Maxwell's equations. Hertz's oscillator was the first radio transmitter. Maxwell's theory and Hertz's experiment gave Guglielmo Marconi the idea of using electro-magnetic waves to transmit messages around the world.
Guglielmo Marconi and the Invention of Wireless Telegraphy
Guglielmo Marconi, an Italian physicist born in 1874, was the inventor of wireless telegraphy. As a young boy he had a fascination with electricity and was even taught Morse code by a family friend. As Marconi's daughter Degna relates in her book, My Father, Marconi , Marconi,while spending the summer of 1894 in the Alps, picked up an Italian electrical journal and found an article about Heinrich Hertz (who had just died earlier that year) and his work on electromagnetic waves. The article was written by Augusto Righi whose lectures Marconi had audited the previous winter. Marconi was excited about the possibilities of using transmitters to send signals in the same way that electric wires transmitted electromagnetic waves. Degna Marconi: "If this was a turning point in my father's life, it was also, in a real sense, a turning point in the evolution of the world we know and take for granted" (11).
Marconi began experimenting on his father's estate using an induction coil with a spark discharger controlled by a Morse key at the sending end and a coherer at the receiving end. "Because Marconi was untrained as a scientist he achieved his results more through experimentation and reasoning" (12) and after countless experiments he succeeded in transmitting wireless signals to a receiver more than eighteen hundred yards away, farther than any other scientist.
Receiving little encouragement in Italy, in 1896 Marconi went to London where he got a job with the British Post Office. Further experiments led to his being able to transmit wireless signals nine miles. He got his first patent in 1896 and gave a series of successful demonstrations in which he used balloons and kites to obtain greater height for his aerials. He was able to send signals over greater and greater distances. In 1897, with the help of wealthy relatives, he set up the Wireless Telegraph and Signal Company. These activities attracted a great deal of international attention; he was invited back to Italy. In 1897 Marconi went to La Spezia where a land station was erected and communication was established with Italian warships at distances up to 19 km. A lot of skepticism still remained about the use of this discovery. But Marconi's cousin Jameson Davis helped finance his patent and set up the wireless Telegraph and Signal Company (later Marconi's Wireless Telegraph Company Ltd.).
In 1899 a wireless station in England communicated with a station in France (distance 50 km) and battleships exchanged messages at 121 km. In September 1899 Marconi equipped U.S. ships to report to newspapers in New York City the progress of the yacht race for America's Cup. The success of this demonstration aroused considerable excitement and led to the formation of the American Marconi Company. The following year Marconi International Marine Communications Company, Ltd. was established for the purpose of installing and operating services between ship and land stations.
Many mathematicians believed that the curvature of the earth would limit practical communication by electrical waves to a distance not exceeding 161-322 km, but Marconi in December 1901 received messages sent across the Atlantic Ocean from Cornwall, England to Newfoundland. This achievement caused extreme excitement and became the starting point for the development of radio communications. In 1909 Guglielmo Marconi and Karl Ferdinand Braun won the Nobel Prize in physics for wireless telegraphy.
Maritime Use of Wireless Telegraphy
In the summer of 1898 the Dublin Daily Express requested that the Marconi Company undertake supplying a minute-by-minute account of the Kingstown regatta. Marconi chartered the tugboat Flying Huntress and reported on the details of a yacht race. He sent more than 700 messages to shore. Newspapers printed stories about the race before the yachts had returned to shore.
The first British ship to use Marconi wireless was the royal yacht, Osbourne. On board was the Prince of Wales who had suffered a knee injury and preferred to recuperate on the yacht rather than at Osbourne House with his mother, Queen Victoria. The queen invited Marconi to set up wireless communication between Lakewood Cottage on the grounds of Osbourne house and the royal yacht. During the next sixteen days, a hundred and fifty messages went between the yacht and the house (13).
Marconi wireless was gathering lots of attention. Ship owners, impressed by his ability to send messages over water, began purchasing wireless systems and installing them on their vessels. One use was for the ships to signal receiving stations as they approached the coast. Like lighthouses and foghorns, wireless stations could provide warnings and locations. But only wireless was helpful in all weather conditions.
Wireless also contributed to rescue operations. On March 3, 1899, a message was received from the East Goodwing Lightship which had been rammed in heavy fog by the steamer M.F.Matthews. A wireless message went out asking for a life boat.
By 1900 Marconi's company was the largest wireless company in the world. Ships outfitted with Marconi systems regularly communicated with other ships and stations on land. However, there was as yet no worldwide wireless communication network. And Marconi knew that a link between Europe and America was crucial. But how could messages be sent such a long distance? He built stations in Newfoundland, the closet point in North America to Europe, and in Polhu on the western coast of England. He experimented with various sizes of antennas, and increased the power of transmitters. On December 1, 1901, the first message spanned the Atlantic. However, reliable wireless transmission across the Atlantic took over five more years to perfect.
By 1912, hundred of ships had Marconi machines; only a very few had the equipment of competitors. Marconi also built a ring of stations on the North American coast with a very important one at Cape Race on the eastern tip of New Foundland which provided information about snow and ice to shipping in the North Atlantic.
To promote wireless in the United States Marconi journeyed to America to report the America's Cup races for the New York Herald. When the race was postponed because of poor weather, a rumor started that one of the ships had gone down. The Herald wired Marconi at sea who wired back that the boat was safe (14).
By 1912 wireless was still regarded as a novelty and there were no procedures for handling the many messages received, some of which were addressed to the captain, others to the ship, and others that were to be relayed elsewhere. Operators were not trained navigators so they were not able to necessarily see the significance of some messages. By 1912 all passenger ships were equipped with wireless equipment, the vast majority of which was supplied and manned by Marconi Company employees. This represented a real safety improvement particularly for vessels in the ice-ridden North Atlantic lanes where previous warnings came from vessels which had arrived in port and therefore whose information was very dated.
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However, use of wireless was still very erratic. The range was short, operators were inexperienced and not trained in navigation, much time was spent relaying messages between ships at sea and those in contact with a land station, and much of the traffic was frivolous personal messages (15). Not all wireless shacks were manned and operated around the clock. In short the use of wireless in the maritime industry was in its infancy and was not yet regarded as an important navigational aid. This attitude was to have a major impact in the Titanic tragedy.