Summary

Alexander Graham Bell (Edinburgh, Scotland, United Kingdom, March 3, 1847-Beinn Bhreagh, Cape Breton Island, Canada, August 2, 1922) was a British scientist, inventor and speech therapist, naturalized American. He contributed to the development of telecommunications.

After a series of procedures (which would last for years in the form of legal claims), in 1876 he patented the telephone in the United States, despite the fact that the device had already been developed earlier by the Italian Antonio Meucci, who was officially recognized posthumously in the United States as the inventor of the telephone more than 120 years later, on June 11, 2002. Regardless of this, the company that Bell created to exploit the patent, the Bell Telephone Company, was the protagonist of the first steps of the rapid implementation of the telephone as a means of mass communication on an international scale.

Many other inventions occupied much of Bell's life, including the construction of the hydrofoil and studies in aeronautics.

His father, grandfather and brother were all associated with work in phonation and speech, which profoundly influenced Bell's interest in listening and speech research, as well as his experiments with hearing apparatus.

In 1888, Alexander Graham Bell was one of the founders of the National Geographic Society and on January 7, 1898, he assumed the presidency of that institution.

Alexander Bell was born in Edinburgh, Scotland, on March 3, 1847. The family home was located at 16 South Charlotte Street, Edinburgh, and has a commemorative plaque near the door, marking it as the place of his birth. He was the son of Professor Alexander Melville Bell and Eliza Grace. He had two brothers, Melville James Bell (1845-1870) and Edward Charles Bell (1848-1867), who died of tuberculosis. At birth he was named Alexander. Later, he begged his father to give him a middle name, as he had done with his two brothers. On the occasion of his eleventh birthday, his father allowed him to adopt "Graham" as his middle name, due to the great admiration he felt for a Canadian friend of the family named Alexander Graham. In private, Alexander Graham was known as "Aleck", a name that his father continued to use when Alexander was already an adult.

First invention

His best friend was Ben Herdman, a neighbor whose family operated a flour mill. On one occasion when the two friends, Ben and Aleck, got into mischief, John Herdman (Ben's father) scolded them, saying, "Why don't you do something useful?" Aleck asked what needed to be done in the mill and was told to husk wheat, something that was done by a tedious process. So, at the age of 12, Bell built a homemade device that combined the rotating paddles with the nail brush systems, creating a simple husking machine that worked and was used for many years. In gratitude, John Herdman gave them a small workshop so they could "invent".

Early work with speech

Bell had inherited from his mother a sensitive nature and a particular talent for art, poetry and music. He played the piano without lessons and was the family pianist. Despite his reserved and introspective nature, he possessed a talent for mime and "voice tricks" related to ventriloquism, with which he entertained guests. Alexander was also sensitized by his mother's gradual deafness (she began to lose her sense of hearing when Bell was only 12 years old). Bell and his mother developed a sign language with which Bell could discreetly convey the family conversation to her. He also developed a technique of speech in clear tones, modulated directly in front of his mother, where she would hear him with reasonable clarity. It was Bell's concern for his mother's deafness that led him to study acoustics.

His family was associated with the teaching of speech: his grandfather, Alexander Bell in London, his uncle in Dublin, and his father in Edinburgh, were all speakers. His father published a variety of works on the subject, many of which are still known, especially his work The Standard Elocutionist (1860) and Treatise on Visible Speech, which appeared in Edinburgh in 1868. The Standard Elocutionist was published in 168 British editions and sold over a quarter of a million copies in the United States alone. In the book, his methods for teaching mutes to articulate words and to read the movement of other people's lips to decipher their meaning are explained. Alexander's father taught him and his siblings sign language (which he then called visible speech), as well as how to identify any symbol and its sound. Alexander was so efficient at this task that he became part of his father's public demonstrations, presenting his abilities by deciphering in Latin, Gaelic and even Sanskrit symbols, the messages his father transmitted to him through sign language.

Education

Like his siblings, Bell received his early schooling at his father's home. He was then enrolled at the Royal High School in Edinburgh, Scotland, which he left at the age of 15. He was not an outstanding pupil at school, but, on the contrary, was truant and obtained mediocre grades. His main interest was in the sciences, especially biology, and he showed indifference to all other school subjects, much to the dismay of his demanding father.

After leaving school, Bell went to London to live with his grandfather, Alexander Bell. During the year he spent with his grandfather, a love of learning grew in him, spending long hours of study and having serious discussions. His grandfather devoted great effort to ensuring that his young grandson learned to speak clearly and with conviction, qualities he would need to become a teacher. At the age of 16, Bell secured a position as an apprentice speech and music teacher at Weston House Academy, in Elgin, Moray, Scotland. Although a student of Latin and Greek, he taught in a permanent position at £10 per session. The following year he attended Edinburgh University, meeting his older brother Melville who had enrolled there the previous year, and where Alexander set out to take the exams but later graduated from the University of Toronto.

First experiments with sound

Their father stimulated his sons' interest in speech and, in 1863, took them to see an automaton made by Sir Charles Wheatstone based on the earlier work of Baron Wolfgang von Kempelen. The rudimentary "mechanical man" had the peculiarity that it simulated a human voice. Alexander was fascinated by the machine and obtained a copy of von Kempelen's book published in Germany, which he roughly translated and, with that information, Alexander and his older brother Melville built their own automaton head. Their father, very interested in the project, paid for the materials, and while his brother built the throat and larynx, Alexander did the more difficult task, recreating a realistic skull. Their efforts resulted in a remarkable head that could "speak" a few words. The boys carefully adjusted the "lips" so that a stream of pressurized air passed through the trachea and produced the very recognizable "mama" sound. The invention pleased the neighbors.

Intrigued by the automaton's results, Bell continued experimenting with a living creature, the family's Skye terrier, Trouve. After Bell taught him to growl continuously, Aleck would reach into his mouth and manipulate the dog's lips and vocal cords to produce a crude "Ow ah oo ga ga ma ma" sound. Visitors believed his dog could articulate "How are you grandma?" and his experiment convinced onlookers that they had seen "a talking dog." However, these initial experiments by Bell led him to undertake his first serious work on sound transmission, using tuning forks to explore resonance. At the age of 19, he wrote a report of his work and sent it to Alexander Ellis, a colleague of his father's, and Ellis responded immediately, stating that the experiments were similar to existing work in Germany.

Dismayed to learn that the work had already been done by Hermann von Helmholtz, who had transported a sound vowel by means of a similar tuning fork, Bell set about studying the German scientist's book, Sensation of Tone. From his translation of the original German edition, Alexander made a conjecture from which he would develop all his future work on sound transmission: "Without knowing much about the subject, it seems to me that if a sound vowel can be produced by electrical means, so could consonants be produced, enabling speech to be articulated".

Family tragedy

In 1865, when the Bell family moved to London, Alexander returned to Weston House as an assistant and in his spare time, continued his sound experiments using basic laboratory equipment. There he concentrated on experimenting with electricity to transmit sound and then installed a telegraph wire from his room at Somerset College to a friend's room. During the fall and winter, his health worsened, experiencing marked fatigue. His younger brother, Edward (Ted) was similarly hospitalized, diagnosed with tuberculosis. While Alexander recovered, he served the following year as an instructor at Somerset College. His brother's health continued to deteriorate, however, and he would eventually pass away. After his brother's death, Bell returned home in 1867. His older brother, Melly, married and moved away, with aspirations of obtaining a degree at the University of London, Bell spent the next few years preparing for the entrance examinations, using his spare time at his family's residence to study.

Collaborating with his father on sign language demonstrations and readings, Bell attended Susanna E. Hull's private school for the deaf in South Kensington, London. Hull's private school for the deaf in South Kensington, London. Her first two pupils were "deaf-mutes," who made remarkable progress under her tutelage. Meanwhile, his older brother seemed to achieve success on many fronts, including founding his own school for speech, focusing on patenting an invention, and starting a family. In May 1870, Melville dies from a complication of tuberculosis, causing a family crisis. His father had also suffered a debilitating illness earlier and had healed after a convalescence in Newfoundland and Labrador. Bell's parents brought forward a long-planned move when they realized that their remaining son was also ill. Making a snap judgment, Alexander Melville Bell consulted Bell in order to sell all the family property, concluding all his brother's affairs (Bell took one last pupil, curing a pronounced lisp) and joined with his mother and father in the idea of leaving for the New World. Bell, therefore, had to conclude his relationship with Marie Eccleston, who admitted she was not prepared to leave England with him.

In 1870, Bell, his parents and his brother's widow, Caroline (Margaret Ottaway), boarded the SS Nestorian for Canada. After arriving in Quebec, they traveled by train to Montreal and then to Paris, Ontario to meet with Reverend Thomas Henderson, a family friend. After a short stay at the Reverend's home, they purchased a ten and a half acre farm in Tutelo Heights (now called Tutela Heights), near Brantford, Ontario. The property consisted of an orchard, a large house, a barn, a chicken coop, and a carriage house, all bordering the Grand River.

Bell set up his workshop in the garage, next to his "dream place," a large space surrounded by trees at the back of the property bordering the river. Despite his frail condition, Bell found the Canadian climate to his liking, and quickly adapted. His interest in the study of the human voice continued when he discovered the Six Nations Reserve across the river in Onondaga. There he learned the Mohawk language and translated it into sign language. For that work, he was awarded the distinction of honorary chief and even participated in a ceremony, where he wore Mohawk dress and danced their traditional dances.

After setting up his workshop, Bell continued his experiments with electricity and sound. He designed a piano that could transmit its music remotely through electricity. Once settled, Bell and his father made plans to establish a teaching practice. In 1871 he accompanied his father to Montreal, where Melville offered him a position to teach his system for visible speech or sign language.

Subsequently, his father was invited by Sarah Fuller, rector of the Boston School for Deaf Mutes (a school for the deaf and hard of hearing that continues today as The Horace Mann School for the Deaf and Hard of Hearing), in Boston, Massachusetts, United States, to train his instructors in the "Visible Speech System" or sign language, but he declined the offer, giving his place to his son. Bell traveled to Boston in April 1871 and completed a successful training plan and was subsequently asked to repeat the program at the American School for the Deaf and Dumb in Hartford and the Clarke School for the Deaf in Northampton.

Returning home to Brantford after six months abroad, Bell continued his experiments with his "harmonic telegraph." The basic concept behind the device was that messages could be sent over the same wire as long as each message was transmitted on a different pulse. Unsure of his future, he contemplated returning to London to finish his studies, but decided to return to Boston as a teacher.

His father helped him in his early days by contacting Gardiner Greene Hubbard, the president of the Clarke School for the Deaf, from whom he obtained a recommendation. Teaching his father's system in October 1872, Alexander opened a school in Boston called Vocal Physiology and Mechanics of Speech, which attracted a large number of deaf pupils (his first class was attended by 30 students). Working as a private tutor, one of his most famous students was Helen Keller, who attended classes with Bell from an early age, without the ability to see, speak or hear. Keller would later say that Bell had dedicated his life to penetrating the "inhuman silence that separates and strangles.

The history of the invention of the telephone is marked from its origins by a succession of lawsuits, accusations and suspicions about Alexander Graham Bell's actions regarding the legality of his patent. Already in his time, he had to face more than 600 lawsuits from his competitors, including those of the inventor Elisha Gray (defending the priority of his patent after it had expired) and Antonio Meucci (an Italian inventor whose patents had disappeared from the register). Bell was always able to assert his rights in court, so for over a hundred years he has been regarded as the inventor of the telephone. However, a 2002 resolution of the U.S. House of Representatives declared Antonio Meucci to be the rightful inventor of the telephone.

There is no doubt that it was Bell (after perfecting the telephone by buying Edison's carbon microphone patent), who turned it into a means of mass communication by founding the Bell Telephone Company, regardless of whether he had the original idea or not.

Initial work

By 1874, Bell's early work on the "harmonic telegraph" had entered a stage of consolidation, with progress made both at his new laboratory in Boston (a rented facility) and at his family home in Canada. While working that summer in Brantford, Bell experimented with a "phonoautograph," a pen-like machine that could draw sound waveforms on smoked glass by tracing their vibrations. Bell thought it might be possible to generate undulating electric currents that corresponded to sound waves. He also thought that by using various metal reeds tuned to different frequencies (as in a mouth harp) he could convert the undulating currents into sound. But he had no working model to demonstrate the feasibility of these ideas.

By 1874, telegraph message traffic was expanding rapidly and in the words of Western Union President William Orton, had become "the nervous system of commerce." Orton had hired inventors Thomas Alva Edison and Elisha Gray to find a way to send multiple telegraph messages on each telegraph line to avoid the great cost of building new lines.

When Bell mentioned to Gardiner Hubbard and Thomas Sanders that he was working on a method of sending multiple tones on a telegraph wire using a multi-prong device, the two wealthy promoters began to financially support Bell's experiments. Patent matters would be handled by Hubbard's attorney, Anthony Pollok.

In March 1875, Bell and Pollok visited the famous scientist Joseph Henry, who was then director of the Smithsonian Institution, and asked his opinion of the multi-pronged electrical apparatus with which Bell hoped to transmit the human voice by telegraph. Henry replied that Bell had "the germ of a great invention." When Bell said he did not have the necessary knowledge, Henry replied, "Get it!" That statement greatly encouraged Bell to keep trying, even though he did not have the necessary equipment to continue his experiments, nor the ability to create a working model of his ideas. However, a chance meeting in 1874 between Bell and Thomas A. Watson, an experienced electrical designer and mechanic in Charles Williams' electrical machine store, changed the situation completely.

With financial support from Sanders and Hubbard, Bell hired Thomas Watson as his assistant, and the two men continued to experiment with harmonic telegraphy. On June 2, 1875, Watson accidentally tore off one of the reeds and Bell, at the receiving end of the wire, heard the overtones of the reed; the harmonics that would be necessary to transmit speech, showing him that only one reed or armature was needed, not several. This led to reconsideration of the self-excited telephone, which could transmit both speech and sounds interchangeably, but still could not transmit words with the necessary clarity.

The race to the patent office

In 1875, Bell developed a harmonic telegraph, for which he applied for a patent. Since he had agreed to share the profits made in the United States with his investors Gardiner Hubbard and Thomas Sanders, Bell requested that an associate in Ontario, Canadian politician George Brown, attempt to patent it in Britain, instructing his lawyers to apply for a patent in the United States only after receiving confirmation of the patent in Britain (Britain at the time only issued patents for discoveries not previously patented elsewhere).

Meanwhile, Elisha Gray was also experimenting with acoustic telegraphy and was thinking of a way to transmit speech using a water transmitter. On February 14, 1876, Gray filed a simplified patent (without an examination of patentable subject matter, and with a duration of one year) with the U.S. Patent Office on a telephone design using a water transmitter. That same morning, Bell's attorney submitted Bell's application to the patent office. There is considerable debate about who got there first, and Gray subsequently challenged the primacy of Bell's patent. Bell was in Boston on February 14 and did not arrive in Washington until February 26.

Patent 174,465, was issued to Bell on March 7, 1876, by the United States Patent and Trademark Office. It covered "the method and apparatus for transmitting vocal or other sounds telegraphically ... causing electrical undulations similar in form to the vibrations of the air accompanying such vocal or other sound." Bell returned to Boston the same day, and the next day resumed work, drawing in his notebook a diagram similar to the one Gray patented.

On March 10, 1876, three days after his patent was issued, Bell got his telephone to work, using a liquid transmitter similar to Gray's design. The vibration of the diaphragm caused a needle to vibrate in water, varying the electrical resistance in the circuit. When Bell uttered the famous phrase "Mr. Watson-come here-I want to see you" into the liquid transmitter, Watson, listening at the receiving end in an adjoining room, received the words clearly.

Although Bell was, and still is, accused of stealing Gray's telephone, he used Gray's water transmitter design only after his own patent was granted, and only as a conceptual scientific experiment, to satiate his curiosity by confirming that his "Speech" (Bell's words) could be transmitted electrically. After March 1876, Bell focused on improving the electromagnetic telephone and never used Gray's liquid transmitter in public demonstrations or for commercial use.

The issue of priority of the use of the variable electrical resistance in the telephone was raised by the examiner before Bell's patent application was approved. He told Bell that his claim to the variable resistance feature was also described in Gray's application. Bell pointed to a variable resistance device in one of his earlier patents, which described a vessel filled with mercury, not water. He had filed the application for the device with mercury with the patent office a year earlier, on February 25, 1875, long before Elisha Gray described the device with water. Moreover, Gray did not renew his patent application, and because he did not challenge Bell's priority, the examiner approved Bell's patent on March 3, 1876. Gray had reinvented the variable resistance telephone, but Bell was the first to document the idea and the first to successfully test it in a telephone.

The patent examiner, Zenas Fisk Wilber, later stated in a notarized record that he was an alcoholic who was heavily indebted to Bell's attorney, Marcellus Bailey, with whom he had served in the Civil War. He claimed that he had shown Gray's patent to Bailey. Wilber also claimed (after Bell arrived in Washington DC from Boston) that he showed Gray's patent to Bell, and that Bell paid him $100. Bell claimed that they discussed the patent only in general terms, although in a letter to Gray, Bell admitted that he learned some technical details. Bell recorded in a notarial deed that he had never given money to Wilber.

Further progress

Continuing his experiments in Brantford, Bell took home a working model of his telephone. On August 3, 1876, from the telegraph office at Mount Pleasant, five miles away from Brantford, Bell sent a tentative telegram indicating that it was ready. With an office full of curious onlookers as witnesses, faint voices could be heard through the device. The next night he surprised guests and his family when he received a message at his Brantford home, from a distance of six kilometers through an improvised wire tied to telegraph lines and fences, and placed through a tunnel. This time, people in the office could clearly hear people reading and singing from Brantford. These experiments proved conclusively that the telephone could work over long distances.

Bell and his partners, Hubbard and Sanders, offered to sell the patent directly to Western Union for $100,000. The president of Western Union turned down the offer, arguing that the phone was nothing more than a toy. Two years later, he told his colleagues that if he could get the patent for $25 million, he would consider it a bargain. By then, Bell's company no longer wanted to sell the patent. Bell's investors would become millionaires, while Bell managed well with his share of the business and at one point accumulated assets worth nearly $1 million.

Bell began a series of demonstrations and public lectures to introduce the new means of communication to the scientific community as well as to the general public. In 1872, he showed the telephone to U.S. President Rutherford B. Hayes, who told him it was a great invention, but wondered who would want to use it. His demonstration at the 1876 Philadelphia Centennial Exposition made the telephone headline news around the world the next day. Influential visitors such as Emperor Pedro II of Brazil were able to observe the invention. Later, Bell would have the opportunity to personally show the telephone to William Thomson, 1st Baron Kelvin, the renowned Scottish scientist renowned for his studies in thermodynamics, and even to Queen Victoria I of the United Kingdom, who requested a private audience at Osborne Castle, at her home on the Isle of Wight. The queen called the demonstration extraordinary. The enthusiasm surrounding Bell's public demonstrations helped the revolutionary device gain acceptance.

The Bell Telephone Company was created in 1877 and by 1886, more than 150,000 people in the United States owned telephones. Bell Company engineers introduced numerous improvements to the telephone, which became one of the most successful products. In 1879, the Bell Company acquired Edison's patents for the carbon microphone from the Western Union. This made the telephone practical for long distances, unlike Bell's voice-operated transmitter that required users to shout into it to be heard on the receiving telephone, even over short distances. On January 25, 1915 Alexander Graham Bell sent the first transcontinental telephone call, from 15 Day Street in New York City, which was received by Thomas Watson at 333 Grant Avenue in San Francisco, California. The New York Times reported:

The figure of Bell was used repeatedly by AT&T and group companies in their advertising, as part of an elaborate image policy. Despite his presence at ceremonies, he played no active role in the technical development of the business built around his patent.

Competitors

For 18 years, the Bell Telephone Company faced 600 lawsuits from inventors claiming to have invented the telephone, without losing a single case. Bell's laboratory notes and letters to the family were the key to accurately establishing the dates of the origin of his experiments.

One of the main lawsuits was brought by Italian inventor Antonio Meucci, who claimed to have created the first working model of a telephone in Italy in 1834. In 1876, Meucci took Bell to court to establish his priority. Meucci's working models had reportedly been misplaced by the exact same Western Union laboratory where Bell conducted his experiments. Meucci lost his case because of the lack of material evidence of his inventions. Meucci's work, like that of many other inventors of the period, was based on earlier acoustical principles.

Paradoxically, more than a hundred years later, thanks to the efforts of Congressman Vito Fossella, Resolution 269 of the U.S. House of Representatives on June 11, 2002, ruled that Meucci's work in inventing the telephone should be recognized, although this moral decision has no material consequences.

However, Bell had to deal until his death with litigation concerning the telephone patent, such as when he was late in paying the fee for the German patent and the electrical firm Siemens and Halske (S&H) became a rival manufacturer of Bell telephones under its own patent, producing nearly identical copies of the Bell telephone without paying royalties. A series of agreements in other countries eventually consolidated the telephone's global rollout.

The tension caused at Bell by his constant court appearances, necessitated by numerous legal battles, led to his resignation from the company. Many cases were repetitive, and were settled due to the resignation of his rivals over time, such as the lawsuit by inventor Elisha Gray (who had also patented a telephone device on his own and claimed his rights in court).

In 2013 Smithsonian researchers recovered Graham Bell's voice, recorded on wax and cardboard discs from 125 years ago, using optical technology.

Posthumous vindication of Antonio Meucci as inventor of the telephone

On June 11, 2002, the U.S. House of Representatives published Resolution No. 269, honoring the life and work of Italian-American inventor Antonio Meucci (1808-1889). It recognizes that it was not Alexander Graham Bell who invented the telephone, but Meucci. It also states that Meucci demonstrated and published his invention in 1860, concluding with an acknowledgement of his authorship of the invention.

On July 11, 1877, a few days after the Bell Telephone Company was founded, Bell married Mabel Hubbard (1857-1923) at the Hubbard estate in Cambridge, Massachusetts, and shortly thereafter, embarked on a year-long honeymoon in Europe. During this trip, Bell took a model of his telephone with him.

Although the courtship had begun years earlier, Bell waited until he was financially secure before marrying. Although the telephone appeared to be an "immediate" success, it was not initially a profitable venture and Bell's main sources of income were lectures until after 1897. They would have four children: Elisa (Elsie) May Bell (1878-1964) who would marry Gilbert Grosvenor, editor of the National Geographic Society, Marian Hubbard Bell (known as Daisy) (1880-1962) and two other children who died in infancy.

In 1882, Bell became a naturalized U.S. citizen. Bell's family maintained their residence in Washington, D. C., where Bell set up his laboratory. In 1915, he described his status as, "I am not one of those 'hyphenated Americans' who claim allegiance to two countries." Despite this statement, Bell would be claimed as a "native son" by Canada, Scotland, and the U.S. By the summer of 1885, the Bell's had a vacation on Cape Breton Island, Nova Scotia, spending time in the small village of Baddeck. Upon returning in 1886, Bell began building a property in the middle of the Baddeck countryside, overlooking Bras d'Or Lake. By 1889 there was a large house, christened The Lodge, and two years later construction began on a larger complex of buildings, which the Bell's would name Beinn Bhreagh (Gaelic: 'beautiful mountain') in honor of Alexander's ancestral Scottish Highlands. Bell would spend his last days and some of his most productive years at the Washington D. C. residence and at Beinn Bhreagh.

Although Alexander Graham Bell is most associated with the invention of the telephone, his interests were wide-ranging. According to one of his biographers, Charlotte Gray, Bell's work swung "unfettered across the scientific landscape" and he often went to bed voraciously reading the Encyclopedia Britannica, triggering new areas of interest. The breadth of Bell's inventive genius is represented only in part by the 18 patents granted in his own name alone and the 12 others he shared with his collaborators. Included in all are 14 for the telephone and telegraph, four for the photophone, one for the phonograph, five for aerial vehicles, four for "hydrofoils" and two for selenium cells. Bell's inventions spanned a wide range of interests and included an "iron lung" to aid in breathing, an audiometer to detect mild hearing problems, a device for locating icebergs, research on how to separate salt from seawater, and his work in the search for alternative fuels.

He worked extensively in medical research and invented techniques for teaching speech to the deaf. During his tenure at Volta Laboratory, Bell and his associates considered the possibility of recording a magnetic field on a disk as a means of sound reproduction. Although the trio experimented briefly with the concept, they were unable to develop a viable prototype. They abandoned the idea, not realizing that they had glimpsed a basic principle that would one day find application in the tape recorder, hard disk drives, floppy disks and other magnetic storage media.

Bell's own house used a primitive form of air conditioning, with fans driving air currents through large blocks of ice. He also anticipated modern concerns such as fuel shortages and industrial pollution. Methane gas, he reasoned, could be produced from farm and factory waste. In his Canadian state of Nova Scotia, he experimented with composting waste and devices to capture water from the atmosphere. In a magazine interview published shortly before his death, he pondered the possibility of using photovoltaic solar panels to heat homes.

Photophone

Bell and his assistant Charles Sumner Tainter jointly invented a cordless telephone, the so-called photophone, which enabled the transmission of normal human sounds and conversations by a beam of light. The two men later became full associates at the Volta Laboratory.

On June 21, 1880, Bell's assistant transmitted a voice message with his mobile telephone system over a considerable distance, from the rooftop of the Franklin School (in Washington DC) to the window of Bell's laboratory, some 200 m away, 19 years before the first radio voice transmission.

Bell considered the principle of the photophone to be the "greatest achievement" of his life, to the point that shortly before his death he told a journalist that "The photophone is the greatest invention I have ever made, greater than the telephone. The photophone was a precursor to the fiber optic communications systems that became popular worldwide in the 1980s. The main patent was issued in December 1880, many decades before the principles of the photophone came into popular use.

Metal detector

Bell is also credited with developing one of the first versions of a metal detector in 1881. The device was quickly developed in an attempt to find the bullet lodged in the body of U.S. President James Garfield after he suffered the assassination attempt that would ultimately end his life a few days later. According to some accounts, the metal detector worked flawlessly in tests, but failed to find the assassin's bullet in part because the metal bed frame on which the president lay disturbed the device's operation. The president's surgeons, who were skeptical of the device ignored Bell's requests to move the president to a bed without metal parts or springs. Alternatively, although Bell had detected a faint sound in his first test, the bullet may have been too deep to be detected by the primitive instrument.

The detailed account of the case written by Bell himself and submitted to the American Association for the Advancement of Science in 1882 differs on several particular points from most of the multiple and varied versions currently in circulation, especially in drawing the conclusion that the outer metal was not responsible for the inability to locate the bullet. Perplexed by the peculiar results he had obtained during an examination of Garfield, Bell "returned to the Presidential Residence the next morning...to check with the surgeons to see if they were absolutely certain that all the metal had been removed from the bed area. It was then that he remembered that underneath the horsehair mattress on which the president lay, there was another mattress formed of steel wires. After obtaining a duplicate, he found that the mattress consisted of a kind of interwoven network of steel wires, with large meshes. The extent of the [area producing a detector response] was so small in comparison with the area of the bed that it seemed reasonable to conclude that the steel mattress had produced no detrimental effect on the device." In a footnote, Bell added that "The death of President Garfield and subsequent postmortem examination, however, showed that the bullet was too far from the surface to be detected by our device."

Hidroala

In March 1906, Scientific American magazine published an article by American pioneer William E. Meacham explaining the basic principle of the hydrofoil and hydrofoil boats. Bell considered the invention of the hydrofoil a very significant achievement. Based on information gained from this article, he began to outline concepts of what is now called a seaplane. Bell and his assistant Frederick W. "Casey" Baldwin began experimentation on a hydrofoil in the summer of 1908 as a possible aid to aircraft takeoff from water. Baldwin studied the work of Italian inventor Enrico Forlanini and began building test models. This led Bell to the development of water vehicles that in practice were hydrofoils.

During their world tour from 1910 to 1911, Bell and Baldwin met Forlanini in France. They took rides in Forlanini's hydrofoil on Lake Maggiore. Baldwin described the experience as smooth as the sensation of flying. Upon returning to Baddeck, a number of initial concepts were developed as experimental models, including the Dhonnas Beag (Scottish Gaelic for Little Devil), the first Bell-Baldwin self-propelled hydrofoil. The experimental boats were essentially prototype test concepts that culminated in the HD-4, a more consolidated design powered by Renault engines. A top speed of 87 km was achieved.

Aeronautics

In 1891, Bell had begun a series of experiments to develop heavier-than-air powered aircraft. The AEA was formed when Bell shared the vision of flight with his wife, who advised him to seek help "young" since he was well into his 60s.

In 1898, Bell experimented with tetrahedral box kites and wings constructed by joining together several such kites lined with crimson silk fabric. Bell was inspired in part by the work of Australian aeronautical engineer Lawrence Hargrave with manned box kites. Hargrave refused to patent his inventions, in a decision similar to Bell's decision not to apply for patents on some of his inventions. Bell also chose the crimson-colored silk because it was highly visible against the light-colored sky for photographic studies of his flying experiences. The tetrahedral wings were named Cygnet I, II and III, and were tested - both manned and unmanned - (Cygnet I crashed during a flight carrying Selfridge) in the period 1907-1912. Some of Bell's kites are currently on display at the Alexander Graham Bell National Historic Site'.

Bell was a supporter of aerospace engineering research through the Aerial Experiment Association (AEA), officially formed in Baddeck, Nova Scotia, in October 1907 at the suggestion of his wife Mabel and with his financial support after the sale of some of his real estate. The AEA was headed by Bell and the founding members were four young men: American Glenn H. Curtiss, then a motorcycle manufacturer who held the title of "fastest man in the world" after riding a self-built motorcycle, and who was later awarded the Scientific American Trophy for the first official one-kilometer flight in the Western Hemisphere, and who later became a world-renowned manufacturer of aircraft; Lt. Thomas Selfridge, an official observer for the U.S. Federal Government and one of the few people in the U.S. who had been awarded the Scientific American Trophy for the first official one-kilometer flight in the Western Hemisphere, and later became a world-renowned manufacturer of aircraft; Lt.  Frederick W. Baldwin, the first British-Canadian to fly a public flight in Hammondsport, New York; and J. A. D. McCurdy. Baldwin and McCurdy were recent engineering graduates of the University of Toronto.

AEA's work progressed to heavier-than-air machines, applying their knowledge of kites to gliders. Moving on to Corning next, the group designed and built the Red Wing, bamboo-framed, covered in red silk and powered by a small air-cooled engine. On March 12, 1908, over Keuka Lake, the biplane took off on the first public flight in North America. Innovations incorporated into this design included a cockpit for the pilot and a tail rudder (later variations on the original design would incorporate ailerons as a means of flight control). One of EAA's inventions, a practical wing edge shape for installing the aileron, would become a standard component on all aircraft. The White Wing and June Bug were to be the next designs and by the end of 1908, more than 150 flights had been made without mishap. However, the EAA had exhausted its initial reserves and only an extraordinary contribution of $15,000 from Mabel Gardiner allowed the experiments to continue. Lt. Selfridge had also become the first person killed in a heavier-than-air powered vehicle flight in an accident with a Wright Model A at Fort Myer, Virginia, on September 17, 1908.

His final aircraft design, the Silver Dart, embodied all the advances made in the earlier aircraft. On February 23, 1909, Bell witnessed the Silver Dart, piloted by McCurdy, make the first flight of the aircraft in Canada from the frozen surface of Bras d'Or. Bell was concerned that the flight was too dangerous and had arranged for a medical team to be present. After the successful flight, the AEA was disbanded and the Silver Dart returned to Baldwin and McCurdy, who founded the Canadian Aerodrome Company and subsequently demonstrated the aircraft to the Canadian Army.

Along with many prominent thinkers and scientists of the time, Bell was associated with the eugenics movement in the United States. In 1881 he investigated the rate of deafness on Martha's Vineyard, Massachusetts and on November 13, 1883 he presented to the National Academy of Sciences his Memoir Upon the Formation of a Deaf Variety of the Human Race where he concluded that congenitally deaf parents were more likely to have deaf children and suggested that couples in which both were deaf should not marry. However, it was his fondness for cattle breeding that led to his appointment to the David Starr Jordan's Committee on Eugenics, under the auspices of the American Breeders' Association. From 1912 to 1918 he chaired the scientific advisory board of the Eugenics Record Office associated with the Cold Spring Harbor Laboratory in New York and regularly attended meetings. He was honorary chairman of the Second International Eugenics Congress held in New York in 1921 under the auspices of the American Museum of Natural History. Organizations such as these advocated (successfully in some states) for the passage of laws providing for the forced sterilization of persons considered, as Bell called them, a "defective variety of the human race." By the late 1930s, about half the states in the U.S. had eugenic laws, and California's laws were a model for eugenic laws in Nazi Germany.

In 1880, Bell received the Volta Prize from the French Academy of Sciences and invested the money obtained with this prize (50,000 francs) in the development of a new project, the photophone, in collaboration with Charles Sumner Tainter. The invention attempted to transmit sound using a beam of light, a precursor of fiber optics. He also worked on one of the first known sound recording systems, based on printing a magnetic field to reproduce sounds. The idea was abandoned when a prototype could not be built; however, the basic principles would find practical applications almost a century later, in magnetic tapes and computers.

Bell received several distinctions, among them the Legion of Honor from the French government, the Volta Prize already mentioned, the Albert Medal of the Royal Society of Arts, the Edison Medal, and a doctorate from the University of Würtzburg. He filed 18 individual patents, and twelve more with his collaborators, among them 14 for the telephone and telegraph, four for the photophone, one for the phonograph, nine for aerial vehicles (including four for hydrofoils) and two for selenium cells. Bell is also credited with the invention of the metal detector in 1881.

Bell died of pernicious anemia on August 2, 1922 at his home in Beinn Bhreagh, Nova Scotia, at the age of 75. His wife Mabel cared for him in his last months. He was buried in the nearby hills. He left a widow and two daughters, Eliza May and Marion.

Sources

1. Alexander Graham Bell
2. Alexander Graham Bell
3. ^ Bell was a British subject for most of his early life. When he moved to Canada in 1870, Canadian and British citizenship were functionally identical, with Canadian citizenship only becoming a formal classification in 1910. He applied for American citizenship after 1877, gained it in 1882, and referred to himself as an American citizen from that point on. Quote from Bell speaking to his wife: "you are a citizen because you can't help it – you were born one, but I chose to be one."[5] Aside from Bell's own view of his citizenship, many, if not most Canadians considered him also as one of theirs as evidenced in an address by the Governor General of Canada. On October 24, 1917, in Brantford, Ontario, the Governor General spoke at the unveiling of the Bell Telephone Memorial to an audience numbering in the thousands, saying: "Dr. Bell is to be congratulated upon being able to receive the recognition of his fellow citizens and fellow countrymen".[6]
4. ^ From Black (1997), p. 18: "He thought he could harness the new electronic technology by creating a machine with a transmitter and receiver that would send sounds telegraphically to help people hear."
5. ^ After Bell's death his wife Mabel wrote to John J. Carty, an AT&T vice-president, and commented on her husband's reluctance to have a phone in his study, saying "[of the statements in the newspapers] ...publishing of Mr. Bell's dislike of the telephone. Of course, he never had one in his study. That was where he went when he wanted to be alone with his thoughts and his work. The telephone, of course, means intrusion by the outside world. And the little difficulties and delays often attending the establishment of conversation... did irritate him, so that as a rule he preferred having others send and receive messages. But all really important business over the telephone he transacted himself. There are few private houses more completely equipped with telephones than ours... and there was nothing that Mr. Bell was more particular about than our telephone service... We never could have come here [to Beinn Bhreagh] in the first place or continued here, but for the telephone which kept us in close touch with doctors and neighbors and the regular telegraph office... Mr. Bell did like to say in fun, "Why did I ever invent the Telephone," but no one had a higher appreciation of its indispensableness or used it more freely when need was—either personally or by deputy—and he was really tremendously proud of it and all it was accomplishing."[10]
6. ^ Bell typically signed his name in full on his correspondence.
7. ^ Helmholtz's The Sensations of Tone is credited with inspiring Bell, at the age of 23, to further his studies of electricity and electromagnetism.[36]
8. Alejandro Graham Bell.José Antonio. Susaeta Ediciones S.A Vidas Ilustres Barcelona, España ISBN 84-305-1109-1 pág. 20. «El Comité de Recompensas de la Exposición (Exposición Conmemorativa del Primer Centenario de la Declaración de Independencia de los Estados Unidos) estudia detenidamente el aparato, que ya había sido patentado y mejorado por Bell en 1876 con el número 174.465».
9. Resolution's sponsor Vito J. Fossella «Rep. Fossella's Resolution Honoring True Inventor of Telephone To Pass House Tonight. Antonio Meucci Receives Recognition 113 Years After His Death». Office of Congressman Vito J. Fossella. 11 de junio de 2002. Archivado desde el original el 24 de enero de 2005. Consultado el 26 de febrero de 2011. «Antonio Meucci never received the recognition he deserved during his lifetime, but this evening – 113 years after his death – the House of Representatives is expected to pass a Resolution honoring his contributions and recognizing him as the true inventor of the telephone. The Resolution was authored by Congressman Vito Fossella (R-NY13). »
10. «Congressional Record - Speech by Prof. Basillio». 5 de septiembre de 2001. Archivado desde el original el 17 de julio de 2011. Consultado el 18 de septiembre de 2015.
11. «Antonio Meucci (1808-1889)». Italian Historical Society. Archivado desde el original el 15 de octubre de 2015. Consultado el 18 de septiembre de 2015.
12. Написание второго имени приведено согласно Большой российской энциклопедии[7] и правилам транскрипции. Встречаются также варианты Грэм, Грэ́хем и Греем[8].
13. Bruce 1990, p. 419.
14. Voir à ce sujet : phonologie et phoniatrie.
15. Black 1997, p. 18. : « Il pensait qu'il pourrait se servir de l'électronique naissante pour créer une machine avec un transmetteur et un receveur qui pourrait envoyer des sons de manière télégraphique et ainsi aider les sourds à entendre. »