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Alexander Graham Bell (March 3, 1847 - August 2, 1922) was a scientist, inventor, and founder of the Bell telephone company. In addition to his work in telecommunications technology, he also was responsible for important advances in aviation and hydrofoil technology.
Formative yearsHe was born Alexander Melville Bell in Edinburgh, Scotland (he later adopted the middle name Graham out of admiration for Alexander Graham, a family friend). His family was associated with the teaching of elocution: his grandfather in London, his uncle in Dublin, and his father, Alexander Melville Bell, in Edinburgh, were all professed elocutionists. The latter has published a variety of works on the subject, several of which are well known, especially his treatise on Visible Speech, which appeared in Edinburgh in 1868. In this he explains his method of instructing deaf mutes, by means of their eyesight, how to articulate words, and also how to read what other persons are saying by the motions of their lips. Graham Bell, his distinguished son, was educated at the Royal High School of Edinburgh, from which he graduated at the age of thirteen. At the age of sixteen he secured a position as a pupil-teacher of elocution and music in Weston House Academy, at Elgin in Morayshire. The next year he spent at the University of Edinburgh. From 1866 to 1867 he was an instructor at Somersetshire College at Bath, England. While still in Scotland he is said to have turned his attention to the science of acoustics, with a view to ameliorate the deafness of his mother. In 1870 he moved with his family to Canada where they settled at Brantford, Ontario. Before he left Scotland, Bell had turned his attention to telephony, and in Canada he continued an interest in communication machines. He designed a piano which could transmit its music to a distance by means of electricity. In 1873 he accompanied his father to Montreal, Quebec, where he was employed in teaching the system of visible speech. The elder Bell was invited to introduce the system into a large day-school for mutes at Boston, but he declined the post in favour of his son, who became Professor of Vocal Physiology and Elocution at Boston University's School of Oratory. At Boston he continued his researches in the same field, and endeavoured to produce a telephone which would not only send musical notes, but articulate speech. With financing from his American father-in-law, on March 7, 1876, the U.S. Patent Office granted him Patent Number 174,465 covering "the method of, and apparatus for, transmitting vocal or other sounds telegraphically . . . by causing electrical undulations, similar in form to the vibrations of the air accompanying the said vocal or other sound.", the telephone. (It should be noted that the question of who invented the telephone continues to be debated. It is clear that several people were researching similar devices. However, supporters of Bell claim that his was the first fully working design. [1] (http://news.bbc.co.uk/1/hi/sci/tech/3253174.stm)) After obtaining the patent for the telephone, Bell continued his experiments in communication, which culminated in the invention of the photophone-transmission of sound on a beam of light -- a precursor of today's optical fiber systems. He also worked in medical research and invented techniques for teaching speech to the deaf. The range of Bell's inventive genius is represented only in part by the 18 patents granted in his name alone and the 12 he shared with his collaborators. These included 14 for the telephone and telegraph, four for the photophone, one for the phonograph, five for aerial vehicles, four for hydroairplanes, and two for a selenium cell. In 1888 he was one of the founding members of the National Geographic Society and became its second president. He was the recipient of many honors. The French Government conferred on him the decoration of the Légion d'honneur (Legion of Honor), the Académie française bestowed on him the Volta Prize of 50,000 Francs, the Royal Society of Arts in London awarded him the Albert medal in 1902, and the University of Würzburg, Bavaria, granted him the Degree of Ph.D. Bell married Mabel Hubbard, who was one of his pupils at Boston University, on July 11, 1877. He died at his estate, Beinn Bhreagh, in Baddeck, Nova Scotia in 1922 and is buried alongside his wife atop Beinn Bhreagh Mountain overlooking Bras d'Or Lake. He was survived by 2 of their 4 children. Bell was named one of the top 10 "Greatest Canadians" by viewers of the Canadian Broadcasting Corporation, despite the fact he was not a native of Canada nor developed the telephone there. Patent warsBell patented his speaking telephone in the United States on March 7, 1876, and by a strange coincidence, Mr. Elisha Gray applied on the same day for another patent of a similar kind. Gray's transmitter is supposed to have been suggested by the very old device known as the 'lovers' telephone,' in which two diaphragms are joined by a taut string, and in speaking against one the voice is conveyed through the string, solely by mechanical vibration, to the other. Gray employed electricity, and varied the strength of the current in conformity with the voice by causing the diaphragm in vibrating to dip a metal probe attached to its centre more or less deep into a well of conducting liquid in circuit with the line. As the current passed from the probe through the liquid to the line a greater or less thickness of liquid intervened as the probe vibrated up and down, and thus the strength of the current was regulated by the resistance offered to the passage of the current. His receiver was an electromagnet having an iron plate as an armature capable of vibrating under the attractions of the varying current. But Gray allowed his idea to slumber, whereas Bell continued to perfect the apparatus designed by Gray. An official at the patent office later admitted to selling Gray's idea to Bell's lawyers for money. Gray never knew this. However, when Bell achieved an unmistakable success, Gray brought a suit against him, which resulted in a compromise, one public company acquiring both patents. Bell's patent has been contested over and over again, and more than one claimant for the honour and reward of being the original inventor of the telephone have appeared. The most interesting case was that of Signor Antonio Meucci, an Italian emigrant, who produced a mass of evidence to show that in 1849, while in Havanna, Cuba, he experimented with the view of transmitting speech by the electric current. He continued his researches in 1852-3, and subsequently at Staten Island, U.S.; and in 1860 deputed a friend visiting Europe to interest people in his invention. In 1871 he filed a caveat in the United States Patent Office, and tried to get Mr. Grant, President of the New York District Telegraph Company, to give the apparatus a trial. Ill health and poverty, consequent on an injury due to an explosion on board the Staten Island ferry boat Westfield, retarded his experiments, and prevented him from completing his patent. Meucci's experimental apparatus was exhibited at the Philadelphia Exhibition of 1884, and attracted much attention. But the evidence he adduces in support of his early claims is that of persons ignorant of electrical science, and the model shown was not complete. In the caveat of 1871 he says 'I employ the well known conducting effect of continuous metallic conductors as a medium for sound, and increase the effect by electrically insulating both the conductor and the parties who are communicating. It forms a speaking telegraph without the necessity of any hollow tube.' In connection with the telephone he used an electric alarm. Bell Telephone CompanyBell and others formed the Bell Telephone Company in July, 1877. In 1879, it merged with the New England Telephone Company forming the National Bell Telephone Company, which was renamed the American Bell Telephone Company in 1880. Along with Thomas Edison, Bell formed the Oriental Telephone Company on January 25, 1881. On March 3, 1885, American Telephone and Telegraph Company (AT&T) was formed to manage the expanding long-distance business of the American Bell Telephone Company. AT&T became the overall holding company for all the Bell ventures, and remains active today. The photophoneAnother of Bell's inventions was the photophone, a device enabling the transmission of sound over a beam of light, which he developed together with Charles Sumner Tainter. The device employed light-sensitive cells of crystalline selenium, which has the property that its electrical resistance varies inversely with the illumination (i.e., the restistance is higher when the material is in the dark, and lower when it is lighted). The basic principle was to modulate a beam of light directed at a receiver made of crystalline selenium, to which a telephone was attached. The modulation was done either by means of a vibrating mirror, or a rotating disk periodically obscuring the light beam. This idea was by no means new. Selenium had been discovered by Jons Jacob Berzelius in 1817, and the peculiar properties of crystalline or granulate selenium were discovered by Willoughby Smith in 1873. In 1878, one writer with the initials J.F.W. from Kew described such an arrangement in Nature in a column appearing on June 13, asking the readers whether any experiments in that direction had already been done. In his paper on the phonophone, Bell credited one A. C. Browne of London with the independent discovery in 1878—the same year Bell became aware of the idea. Bell and Tainter, however, were apparently the first to perform a successful experiment, by no means any easy task, as they even had to produce the selenium cells with the desired resistance characteristics themselves. In one experiment in Washington, D.C. the sender and the receiver were placed on in different buildings some 830 ft. (about 250 m) apart. The sender consisted of a mirror directing sunlight onto the mouthpiece, where the light beam was modulated by a vibrating mirror, focused by a lens and directed at the receiver, which was simply a parabolic reflector with the selenium cells in the focus and the telephone attached. With this setup, Bell and Tainter succeeded to communicate clearly. The photophone was patented on December 18, 1880. However, since the light beam was not shielded in any way against external interferences, the quality of communication that could be achieved remained chancy, and furthermore it only worked within line-of-sight. It is still considered a precursor of the much later fiber optic technology, which is based on the same principles, but does remove these limitations. Metal detectorBell is also credited with the invention of the metal detector in 1881. The device was hurriedly put together in an attempt to find the bullet in the body of U.S. President James Garfield. The metal detector worked, but didn't find the bullet because metal bedframe the President was lying on confused the instrument. Bell gave a full account of his experiments in a paper read before the American Association for the Advancement of Science in August, 1882. The device is considered a forerunner to MRI technology. Experimental aircraftBell was also interested in aircraft and was a supporter of aerospace engineering research through the Aerial Experiment Association. The Association was officially formed at Baddeck, Nova Scotia in October 1907 at the suggestion of Mrs. Mabel Bell and with her financial support. It was headed by the inventor himself. The founding members were four young men, American Glenn H. Curtiss, a motorcycle manufacturer who would later be awarded the Scientific American Trophy for the first official one-kilometre flight in the Western hemisphere and later be world-renowned as an airplane manufacturer; F.W. (Casey) Baldwin, the first Canadian and first British subject to pilot a public flight in Hammondsport, New York; J.A.D. McCurdy; and Lieutenant Thomas Selfridge, an official observer of the U.S. government. One of the project's inventions, the aileron, is a standard component of aircraft today. In 1909 Bell's Silver Dart made the first controlled powered flight in Canada. However, a series of Canadian flights failed to interest the Canadian military in developing the airplane. The hydrofoilsThe March 1906 Scientific American article by American hydrofoil pioneer William E. Meacham explained the basic principle of hydrofoils. Bell considered the invention of the hydroplane as a very significant achievement. Based on information gained from that article he began to sketch concepts of what is now called a hydrofoil boat. Alexander Graham Bell and Casey Baldwin began hydrofoil experimentation in the summer of 1908 as a possible aid to airplane takeoff from water. Baldwin studied the work of the Italian inventor Enrico Forlanini and began testing models. This lead he and Bell to the development of practical hydrofoil watercraft. During his world tour of 1910-1911 Bell and Baldwin met with Forlanini in Italy. They had rides in the Forlanini hydrofoil boat over Lake Maggiore. Baldwin described it was as smooth as flying. On returning to Baddeck a number of designs were tried culminating in the HD-4. Using Renault engines a top speed of 54 miles per hour was achieved accelerating rapidly, taking wave without difficulty, steering well, showing good stability. Bell's report to the navy permitted him to obtain two 350 horsepower (260 kW) engines in July 1919. On September 9, 1919 the HD-4 set a world's marine speed record of 70.86 miles per hour. This record stood for ten years. Bel and decibelThe bel is a measure that was named after him. The bel is so coarse a measure that the tenth of a bel, or "decibel" is what is commonly used. See Acoustics for technical information. EugenicsAlong with many very prominent thinkers and scientists of the time, Bell was connected with the eugenics movement in the United States. From 1912 until 1918 he was the chairman of the board of scientific advisors to the Eugenics Record Office in Cold Spring Harbor, New York, and regularly attended meetings. In 1921 he was the honorary president of the Second International Congress of Eugenics held under the auspices of the American Museum of Natural History in New York. Organizations such as these advocated passing laws (with success in some states) that established the compulsory sterilization of people deemed to be, as Bell called them, a "defective variety of the human race". Much of his thoughts about people he considered defective centered on the deaf because of his long contact with them in relation to his work in deaf education. In addition to advocating sterilization of the deaf, Bell wished to prohibit deaf teachers from being allowed to teach in schools for the deaf, he worked to outlaw the marriage of deaf individuals to one another, and he was an ardent supporter of oralism over manualism. His avowed goal was to eradicate the language and culture of the deaf so as to force them to integrate into the hearing culture for their own long-term benefit and for the benefit of society at large. Although this attitude is widely seen as paternalistic and arrogant today, it was fitting for the time and it mirrored the way the cultures and languages of Native Americans were subjected to many attempts to destroy them and replace them with the "superior" mainstream language and culture. Although he supported what many would consider harsh policies today, he was not unkind to deaf individuals. He was a personal and longtime friend of Hellen Keller and his wife Mabel, a former student of his, was deaf. Together they had children, none of which were deaf. Bell was well known as a kindly father and family man who enjoyed playing with his grandchildren immensely. See alsoExternal links
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