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Thomas Edison | |
"Genius is one percent inspiration, ninety-nine percent perspiration."
– Thomas Alva Edison, Harper's Monthly (September 1932 edition) |
Born | Thomas Alva Edison February 11, 1847 Milan, Ohio, U.S. |
Died | October 18, 1931 West Orange, New Jersey, U.S. |
(aged 84)
Nationality | American |
Education | self educated with visits to the Cooper Union[1] |
Occupation | Inventor, businessman |
Religion | Deist (previously Congregationalist)[2] |
Spouse(s) | Mary Stilwell (m. 1871–84) Mina Miller (m. 1886–1931) |
Children | Marion Estelle Edison (1873–1965) Thomas Alva Edison Jr. (1876–1935) William Leslie Edison (1878–1937) Madeleine Edison (1888–1979) Charles Edison (1890–1969) Theodore Miller Edison (1898–1992) |
Parent(s) | Samuel Ogden Edison, Jr. (1804–1896) Nancy Matthews Elliott (1810–1871) |
Relatives | Lewis Miller (father-in-law) |
Signature |
Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman. He developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb. Dubbed "The Wizard of Menlo Park",[3] he was one of the first inventors to apply the principles of mass production and large-scale teamwork to the process of invention, and because of that, he is often credited with the creation of the first industrial research laboratory.[4]
Edison was a prolific inventor, holding 1,093 US patents in his name, as well as many patents in the United Kingdom, France, and Germany. More significant than the number of Edison's patents was the widespread impact of his inventions: electric light and power utilities, sound recording, and motion pictures all established major new industries world-wide. Edison's inventions contributed to mass communication and, in particular, telecommunications. These included a stock ticker, a mechanical vote recorder, a battery for an electric car, electrical power, recorded music and motion pictures.
His advanced work in these fields was an outgrowth of his early career as a telegraph operator. Edison developed a system of electric-power generation and distribution[5] to homes, businesses, and factories – a crucial development in the modern industrialized world. His first power station was on Pearl Street in Manhattan, New York.[5]
Thomas Edison was born in Milan, Ohio, and grew up in Port Huron, Michigan. He was the seventh and last child of Samuel Ogden Edison, Jr. (1804–1896, born in Marshalltown, Nova Scotia, Canada) and Nancy Matthews Elliott (1810–1871, born in Chenango County, New York).[6] His father had to escape from Canada because he took part in the unsuccessful Mackenzie Rebellion of 1837.[7] Edison reported being of Dutch ancestry.[8]
In school, the young Edison's mind often wandered, and his teacher, the Reverend Engle, was overheard calling him "addled". This ended Edison's three months of official schooling. Edison recalled later, "My mother was the making of me. She was so true, so sure of me; and I felt I had something to live for, someone I must not disappoint." His mother taught him at home.[9] Much of his education came from reading R.G. Parker's School of Natural Philosophy and The Cooper Union.[10]
Edison developed hearing problems at an early age. The cause of his deafness has been attributed to a bout of scarlet fever during childhood and recurring untreated middle-ear infections. Around the middle of his career, Edison attributed the hearing impairment to being struck on the ears by a train conductor when his chemical laboratory in a boxcar caught fire and he was thrown off the train in Smiths Creek, Michigan, along with his apparatus and chemicals. In his later years, he modified the story to say the injury occurred when the conductor, in helping him onto a moving train, lifted him by the ears.[11][12]
Edison's family moved to Port Huron, Michigan, after the railroad bypassed Milan in 1854 and business declined;[13] his life there was bittersweet. Edison sold candy and newspapers on trains running from Port Huron to Detroit, and sold vegetables to supplement his income. He also studied qualitative analysis, and conducted chemical experiments on the train until an accident prohibited further work of the kind.[14]
Edison obtained the exclusive right to sell newspapers on the road, and, with the aid of four assistants, he set in type and printed the Grand Trunk Herald, which he sold with his other papers.[14] This began Edison's long streak of entrepreneurial ventures, as he discovered his talents as a businessman. These talents eventually led him to found 14 companies, including General Electric, which is still one of the largest publicly traded companies in the world.[15][16]
Edison became a telegraph operator after he saved three-year-old Jimmie MacKenzie from being struck by a runaway train. Jimmie's father, station agent J.U. MacKenzie of Mount Clemens, Michigan, was so grateful that he trained Edison as a telegraph operator. Edison's first telegraphy job away from Port Huron was at Stratford Junction, Ontario, on the Grand Trunk Railway.[17]
In 1866, at the age of 19, Edison moved to Louisville, Kentucky, where, as an employee of Western Union, he worked the Associated Press bureau news wire. Edison requested the night shift, which allowed him plenty of time to spend at his two favorite pastimes—reading and experimenting. Eventually, the latter pre-occupation cost him his job. One night in 1867, he was working with a lead–acid battery when he spilled sulfuric acid onto the floor. It ran between the floorboards and onto his boss's desk below. The next morning Edison was fired.[18]
One of his mentors during those early years was a fellow telegrapher and inventor named Franklin Leonard Pope, who allowed the impoverished youth to live and work in the basement of his Elizabeth, New Jersey, home. Some of Edison's earliest inventions were related to telegraphy, including a stock ticker. His first patent was for the electric vote recorder, (U.S. Patent 90,646),[19] which was granted on June 1, 1869.[20]
On December 25, 1871, Edison married 16-year-old Mary Stilwell (1855–1884), whom he had met two months earlier; she was an employee at one of his shops. They had three children:
Mary Edison died at age 29 on August 9, 1884, of unknown causes: possibly from a brain tumor[24] or a morphine overdose. Doctors frequently prescribed morphine to women in those years to treat a variety of causes, and researchers believe that some of her symptoms sounded as if they were associated with morphine poisoning.[25]
On February 24, 1886, at the age of thirty-nine, Edison married the 20-year-old Mina Miller (1866–1947) in Akron, Ohio.[26] She was the daughter of the inventor Lewis Miller, co-founder of the Chautauqua Institution and a benefactor of Methodist charities. They also had three children together:
Mina outlived Thomas Edison, dying on August 24, 1947.[30][31]
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Edison began his career as an inventor in Newark, New Jersey, with the automatic repeater and his other improved telegraphic devices, but the invention that first gained him notice was the phonograph in 1877.[32] This accomplishment was so unexpected by the public at large as to appear almost magical. Edison became known as "The Wizard of Menlo Park," New Jersey.[3]
His first phonograph recorded on tinfoil around a grooved cylinder. Despite its limited sound quality and that the recordings could be played only a few times, the phonograph made Edison a celebrity. Joseph Henry, president of the National Academy of Sciences and one of the most renowned electrical scientists in the US, described Edison as "the most ingenious inventor in this country... or in any other".[33] In April 1878, Edison travelled to Washington to demonstrate the phonograph before the National Academy of Sciences, Congressmen, Senators and US President Hayes.[34] The Washington Post described Edison as a "genius" and his presentation as "a scene... that will live in history".[35] Although Edison obtained a patent for the phonograph in 1878,[36] he did little to develop it until Alexander Graham Bell, Chichester Bell, and Charles Tainter produced a phonograph-like device in the 1880s that used wax-coated cardboard cylinders.
Edison's major innovation was the first industrial research lab, which was built in Menlo Park, a part of Raritan Township, Middlesex County, New Jersey (today named Edison in his honor). It was built with the funds from the sale of Edison's quadruplex telegraph. After his demonstration of the telegraph, Edison was not sure that his original plan to sell it for $4,000 to $5,000 was right, so he asked Western Union to make a bid. He was surprised to hear them offer $10,000 ($208,400 in today's dollars.[37]), which he gratefully accepted.[38] The quadruplex telegraph was Edison's first big financial success, and Menlo Park became the first institution set up with the specific purpose of producing constant technological innovation and improvement. Edison was legally attributed with most of the inventions produced there, though many employees carried out research and development under his direction. His staff was generally told to carry out his directions in conducting research, and he drove them hard to produce results.
William Joseph Hammer, a consulting electrical engineer, began his duties as a laboratory assistant to Edison in December 1879. He assisted in experiments on the telephone, phonograph, electric railway, iron ore separator, electric lighting, and other developing inventions. However, Hammer worked primarily on the incandescent electric lamp and was put in charge of tests and records on that device. In 1880, he was appointed chief engineer of the Edison Lamp Works. In his first year, the plant under General Manager Francis Robbins Upton turned out 50,000 lamps. According to Edison, Hammer was "a pioneer of incandescent electric lighting".[39] Frank J. Sprague, a competent mathematician and former naval officer, was recruited by Edward H. Johnson and joined the Edison organization in 1883. One of Sprague's contributions to the Edison Laboratory at Menlo Park was to expand Edison's mathematical methods. Despite the common belief that Edison did not use mathematics, analysis of his notebooks reveal that he was an astute user of mathematical analysis conducted by his assistants such as Francis Robbins Upton, for example, determining the critical parameters of his electric lighting system including lamp resistance by an analysis of Ohm's Law, Joule's Law and economics.[40]
Nearly all of Edison's patents were utility patents, which were protected for a 17-year period and included inventions or processes that are electrical, mechanical, or chemical in nature. About a dozen were design patents, which protect an ornamental design for up to a 14-year period. As in most patents, the inventions he described were improvements over prior art. The phonograph patent, in contrast, was unprecedented as describing the first device to record and reproduce sounds.[41]
In just over a decade, Edison's Menlo Park laboratory had expanded to occupy two city blocks. Edison said he wanted the lab to have "a stock of almost every conceivable material".[42] A newspaper article printed in 1887 reveals the seriousness of his claim, stating the lab contained "eight thousand kinds of chemicals, every kind of screw made, every size of needle, every kind of cord or wire, hair of humans, horses, hogs, cows, rabbits, goats, minx, camels ... silk in every texture, cocoons, various kinds of hoofs, shark's teeth, deer horns, tortoise shell ... cork, resin, varnish and oil, ostrich feathers, a peacock's tail, jet, amber, rubber, all ores ..." and the list goes on.[43]
Over his desk, Edison displayed a placard with Sir Joshua Reynolds' famous quotation: "There is no expedient to which a man will not resort to avoid the real labor of thinking."[44] This slogan was reputedly posted at several other locations throughout the facility.
With Menlo Park, Edison had created the first industrial laboratory concerned with creating knowledge and then controlling its application.[45]
In 1877–78, Edison invented and developed the carbon microphone used in all telephones along with the Bell receiver until the 1980s. After protracted patent litigation, in 1892 a federal court ruled that Edison and not Emile Berliner was the inventor of the carbon microphone. The carbon microphone was also used in radio broadcasting and public address work through the 1920s.[citation needed]
In 1878 Edison began working on a system of electrical illumination, something he hoped could compete with gas and oil based lighting.[46] He began by tackling the problem of creating a long lasting incandescent lamp, something that would be needed for indoor use. Many earlier inventors had previously devised incandescent lamps, including Alessandro Volta's demonstration of a glowing wire in 1800 and inventions by Henry Woodward and Mathew Evans. Others who developed early and commercially impractical incandescent electric lamps included Humphry Davy, James Bowman Lindsay, Moses G. Farmer,[47] William E. Sawyer, Joseph Swan and Heinrich Göbel. Some of these early bulbs had such flaws as an extremely short life, high expense to produce, and high electric current drawn, making them difficult to apply on a large scale commercially.[48]:217–218 Edison realized that in order to keep the thickness of the copper wire needed to connect a series of electric lights to an economically manageable size he would have to come up with a lamp that would draw a low amount of current. This meant the lamp would have to have a high resistance and run at a low voltage (around 110 volts).[49]
After many experiments, first with carbon filaments and then with platinum and other metals, in the end Edison returned to a carbon filament.[50] The first successful test was on October 22, 1879;[48]:186 it lasted 13.5 hours.[51] Edison continued to improve this design and by November 4, 1879, filed for U.S. patent 223,898 (granted on January 27, 1880) for an electric lamp using "a carbon filament or strip coiled and connected to platina contact wires".[52] This was the first commercially practical incandescent light.[53]
Although the patent described several ways of creating the carbon filament including "cotton and linen thread, wood splints, papers coiled in various ways",[52] it was not until several months after the patent was granted that Edison and his team discovered a carbonized bamboo filament that could last over 1,200 hours. The idea of using this particular raw material originated from Edison's recalling his examination of a few threads from a bamboo fishing pole while relaxing on the shore of Battle Lake in the present-day state of Wyoming, where he and other members of a scientific team had traveled so that they could clearly observe a total eclipse of the sun on July 29, 1878, from the Continental Divide.[54]
In 1878, Edison formed the Edison Electric Light Company in New York City with several financiers, including J. P. Morgan and the members of the Vanderbilt family. Edison made the first public demonstration of his incandescent light bulb on December 31, 1879, in Menlo Park. It was during this time that he said: "We will make electricity so cheap that only the rich will burn candles."[55]
Henry Villard, president of the Oregon Railroad and Navigation Company, had attended Edison's 1879 demonstration. Villard quickly became impressed and requested Edison install his electric lighting system aboard his company's new steamer, the Columbia. Although hesitant at first, Edison relented and agreed to Villard's request. Following most of its completion in May 1880, the Columbia was sent to New York City, where Edison and his personnel installed Columbia's new lighting system. Due to this, the Columbia became Edison's first commercial application for his incandescent light bulb. The Edison equipment was eventually removed from Columbia in 1895.[56][57][58][59]
Lewis Latimer joined the Edison Electric Light Company in 1884. Latimer had received a patent in January 1881 for the "Process of Manufacturing Carbons", an improved method for the production of carbon filaments for lightbulbs. Latimer worked as an engineer, a draftsman and an expert witness in patent litigation on electric lights.[60]
George Westinghouse's company bought Philip Diehl's competing induction lamp patent rights (1882) for $25,000, forcing the holders of the Edison patent to charge a more reasonable rate for the use of the Edison patent rights and lowering the price of the electric lamp.[61]
On October 8, 1883, the US patent office ruled that Edison's patent was based on the work of William Sawyer and was therefore invalid. Litigation continued for nearly six years, until October 6, 1889, when a judge ruled that Edison's electric-light improvement claim for "a filament of carbon of high resistance" was valid.[62] To avoid a possible court battle with Joseph Swan, whose British patent had been awarded a year before Edison's, he and Swan formed a joint company called Ediswan to manufacture and market the invention in Britain.
Mahen Theatre in Brno (in what is now the Czech Republic), which opened in 1882, was the first public building in the world to use Edison's electric lamps, with the installation supervised by Edison's assistant in the invention of the lamp, Francis Jehl.[63] In September 2010, a sculpture of three giant light bulbs was erected in Brno, in front of the theatre.[64]
After devising a commercially viable electric light bulb on October 21, 1879, Edison went on to develop and electric "utility" designed to compete with the then existent gas lighting utilities.[65] In 1889 he patented a system for electricity distribution and on December 17, 1880, he founded the Edison Illuminating Company. The company established the first investor-owned electric utility in 1882 on Pearl Street Station, New York City. It was on September 4, 1882, that Edison switched on his Pearl Street generating station's electrical power distribution system, which provided 110 volts direct current (DC) to 59 customers in lower Manhattan.[66]
Earlier in the year, in January 1882, he had switched on the first steam-generating power station at Holborn Viaduct in London. The DC supply system provided electricity supplies to street lamps and several private dwellings within a short distance of the station. On January 19, 1883, the first standardized incandescent electric lighting system employing overhead wires began service in Roselle, New Jersey.
As Edison was expanding his direct current (DC) power delivery system he began receiving stiff competition from companies installing alternating current (AC) systems. From the early 1880s on AC arc lighting systems for streets and large spaces had been an expanding business in the US. With development of transformers in Europe and by Westinghouse Electric in the US in 1885-1886 it became possible to transmit AC very long distances over thinner and cheaper wires, and "step down" the voltage at the destination for distribution to users. This allowed AC to be used not only in street lighting but also in lighting for small business and domestic customers, the market Edison's patented low voltage DC incandescent lamp system had been designed to supply.[67] Edison's DC empire began suffering from one of its chief drawbacks: it was suitable only for the high density of customers found in large cities. Edison's DC plants could not deliver electricity to customers who were more than one mile from the plant and the short range left a patchwork of un-supplied customers in-between plants. Small cities and rural areas could not afford an Edison style system at all. This left a large part of market without electrical service and AC companies were expanding into this gap.
Edison expressed views that AC was unworkable and the high voltages used were dangerous. As George Westinghouse was installing his first AC systems in 1886, Thomas Edison began a pattern of striking out personally against his chief rival stating, "Just as certain as death, Westinghouse will kill a customer within six months after he puts in a system of any size. He has got a new thing and it will require a great deal of experimenting to get it working practically."[68] Many reasons have been put forward for Edison's anti-AC stance. One notion is that the inventor may not have been able to grasp the more abstract theories behind AC and was trying to avoid developing a system he did not understand. Edison also appeared to have been worried about the high voltage from some competitor's misinstalled AC system killing customers and hurting the sales of electric power systems in general.[69] On top of all that was the simple fact that Edison Electric had based their entire design on low voltage DC and switching a standard after they had installed over 100 systems was, in Edison's mind, out of the question. By the end of 1887 Edison Electric was beginning to lose market share with Westinghouse, who had built 68 AC-based power stations to Edison's 121 DC-based stations. To make matters worse for Edison, the Thomson-Houston Electric Company of Lynn, Massachusetts (another AC-based competitor) had built 22 power stations.[70]
Parallel to the expanding competition between Edison and the AC companies was a rising public furor over a series of deaths in the spring of 1888 caused by pole mounted high voltage alternating current lines that turned into a media frenzy against the current and the seemingly greedy and callous lighting companies that used it.[71][72] Edison took advantage of the public perception that AC was dangerous and teamed up with the self-styled New York anti-AC crusader Harold P. Brown in a propaganda campaign, aiding Brown in the public electrocution of animals with AC as well as supported legislation to control and severely limit AC installations and voltages (to the point of making it an ineffective power delivery system) in what was now being referred to as a "battle of currents". The development of the electric chair was used in an attempt to portray AC as having a greater lethal potential than DC and smear Westinghouse at the same time via Edison colluding with Brown and Westinghouse's chief AC rival, the Thomson-Houston Electric Company, to make sure the first electric chair was powered by a Westinghouse AC generator.
Thomas Edison's staunch anti-AC tactics were not sitting well with his own stock holders. By the early 1890s Edison's company was generating much smaller profits than its AC rivals, and the War of Currents would come to an end in 1892 with Edison being forced out of controlling his own company. That year the financier J P Morgan engineered a merger of Edison General Electric with Thomson-Houston that basically put the board of Thomson-Houston in charge of the new company called General Electric (dropping "Edison" from its name). General Electric now controlled three quarters of the US electrical business and would go on to compete with Westinghouse for the AC market.[73][74]
Edison is credited with designing and producing the first commercially available fluoroscope, a machine that uses X-rays to take radiographs. Until Edison discovered that calcium tungstate fluoroscopy screens produced brighter images than the barium platinocyanide screens originally used by Wilhelm Röntgen, the technology was capable of producing only very faint images.
The fundamental design of Edison's fluoroscope is still in use today, although Edison himself abandoned the project after nearly losing his own eyesight and seriously injuring his assistant, Clarence Dally. Dally had made himself an enthusiastic human guinea pig for the fluoroscopy project and in the process been exposed to a poisonous dose of radiation. He later died of injuries related to the exposure. In 1903, a shaken Edison said "Don't talk to me about X-rays, I am afraid of them."[75]
The key to Edison's fortunes was telegraphy. With knowledge gained from years of working as a telegraph operator, he learned the basics of electricity. This allowed him to make his early fortune with the stock ticker, the first electricity-based broadcast system. On August 9, 1892, Edison received a patent for a two-way telegraph.
Edison was also granted a patent for the motion picture camera or "Kinetograph". He did the electromechanical design, while his employee W.K.L. Dickson, a photographer, worked on the photographic and optical development. Much of the credit for the invention belongs to Dickson.[48] In 1891, Thomas Edison built a Kinetoscope, or peep-hole viewer. This device was installed in penny arcades, where people could watch short, simple films. The kinetograph and kinetoscope were both first publicly exhibited May 20, 1891.[77]
In April 1896, Thomas Armat's Vitascope, manufactured by the Edison factory and marketed in Edison's name, was used to project motion pictures in public screenings in New York City. Later he exhibited motion pictures with voice soundtrack on cylinder recordings, mechanically synchronized with the film.
Officially the kinetoscope entered Europe when the rich American Businessman Irving T. Bush (1869–1948) bought from the Continental Commerce Company of Frank Z. Maguire and Joseph D. Baucus a dozen machines. Bush placed from October 17, 1894, the first kinetoscopes in London. At the same time the French company Kinétoscope Edison Michel et Alexis Werner bought these machines for the market in France. In the last three months of 1894, The Continental Commerce Company sold hundreds of kinetoscopes in Europe (i.e. the Netherlands and Italy). In Germany and in Austria-Hungary the kinetoscope was introduced by the Deutsche-österreichische-Edison-Kinetoscop Gesellschaft, founded by the Ludwig Stollwerck[78] of the Schokoladen-Süsswarenfabrik Stollwerck & Co of Cologne.
The first kinetoscopes arrived in Belgium at the Fairs in early 1895. The Edison's Kinétoscope Français, a Belgian company, was founded in Brussels on January 15, 1895, with the rights to sell the kinetoscopes in Monaco, France and the French colonies. The main investors in this company were Belgian industrialists.[79]
On May 14, 1895, the Edison's Kinétoscope Belge was founded in Brussels. The businessman Ladislas-Victor Lewitzki, living in London but active in Belgium and France, took the initiative in starting this business. He had contacts with Leon Gaumont and the American Mutoscope and Biograph Co. In 1898 he also became a shareholder of the Biograph and Mutoscope Company for France.[79]
Edison's film studio made close to 1,200 films. The majority of the productions were short films showing everything from acrobats to parades to fire calls including titles such as Fred Ott's Sneeze (1894), The Kiss (1896), The Great Train Robbery (1903), Alice's Adventures in Wonderland (1910), and the first Frankenstein film in 1910. In 1903, when the owners of Luna Park, Coney Island announced they would execute Topsy the elephant by strangulation, poisoning, and electrocution (with the electrocution part ultimately killing the elephant), Edison Manufacturing sent a crew to film it, releasing it that same year with the title Electrocuting an Elephant.
As the film business expanded competing exhibitors routinely copied and exhibited each other's films.[80] To better protect the copyrights on his films, Edison deposited prints of them on long strips of photographic paper with the U.S. copyright office. Many of these paper prints survived longer and in better condition than the actual films of that era.[81]
In 1908, Edison started the Motion Picture Patents Company, which was a conglomerate of nine major film studios (commonly known as the Edison Trust). Thomas Edison was the first honorary fellow of the Acoustical Society of America, which was founded in 1929.
Edison said his favorite movie was The Birth of a Nation. He thought that talkies had "spoiled everything" for him. "There isn't any good acting on the screen. They concentrate on the voice now and have forgotten how to act. I can sense it more than you because I am deaf."[82] His favorite stars were Mary Pickford and Clara Bow.[83]
In 1901, Edison visited an industrial exhibition in the Sudbury area in Ontario, Canada and thought nickel and cobalt deposits there could be used in his production of electrical equipment. He returned as a mining prospector, and is credited with the original discovery of the Falconbridge ore body. His attempts to mine the ore body were not successful, however, and he abandoned his mining claim in 1903.[84] A street in Falconbridge, as well as the Edison Building, which served as the head office of Falconbridge Mines, are named for him.
Edison moved from Menlo Park after the death of his first wife, Mary, in 1884, and purchased a home known as "Glenmont" in 1886 as a wedding gift for his second wife, Mina, in Llewellyn Park in West Orange, New Jersey. In 1885, Thomas Edison had bought property in Fort Myers, Florida, and built what was later called Seminole Lodge as a winter retreat. Edison and Mina spent many winters at their home in Fort Myers, and Edison tried to find a domestic source of natural rubber.
In 1928, Edison joined the Fort Myers Civitan Club. He believed strongly in the organization, writing that "The Civitan Club is doing things—big things—for the community, state, and nation, and I certainly consider it an honor to be numbered in its ranks."[85] He was an active member in the club until his death, sometimes bringing Henry Ford to the club's meetings.
Henry Ford, the automobile magnate, later lived a few hundred feet away from Edison at his winter retreat in Fort Myers, Florida. Edison even contributed technology to the automobile. They were friends until Edison's death. Edison was active in business right up to the end. Just months before his death, the Lackawanna Railroad inaugurated suburban electric train service from Hoboken to Montclair, Dover, and Gladstone, New Jersey. Electrical transmission for this service was by means of an overhead catenary system using direct current, which Edison had championed. Despite his frail condition, Edison was at the throttle of the first electric MU (Multiple-Unit) train to depart Lackawanna Terminal in Hoboken in September 1930, driving the train the first mile through Hoboken yard on its way to South Orange.[86]
This fleet of cars would serve commuters in northern New Jersey for the next 54 years until their retirement in 1984. A plaque commemorating Edison's inaugural ride can be seen today in the waiting room of Lackawanna Terminal in Hoboken, which is presently operated by New Jersey Transit.[86]
Edison was said to have been influenced by a popular fad diet in his last few years; "the only liquid he consumed was a pint of milk every three hours".[48] He is reported to have believed this diet would restore his health. However, this tale is doubtful. In 1930, the year before Edison died, Mina said in an interview about him, "correct eating is one of his greatest hobbies." She also said that during one of his periodic "great scientific adventures", Edison would be up at 7:00, have breakfast at 8:00, and be rarely home for lunch or dinner, implying that he continued to have all three.[82]
Edison became the owner of his Milan, Ohio, birthplace in 1906. On his last visit, in 1923, he was reportedly shocked to find his old home still lit by lamps and candles.[citation needed]
Edison died of complications of diabetes on October 18, 1931, in his home, "Glenmont" in Llewellyn Park in West Orange, New Jersey, which he had purchased in 1886 as a wedding gift for Mina. He is buried behind the home.[87][88]
Edison's last breath is reportedly contained in a test tube at the Henry Ford Museum. Ford reportedly convinced Charles Edison to seal a test tube of air in the inventor's room shortly after his death, as a memento. A plaster death mask was also made.[89] Mina died in 1947.
Historian Paul Israel has characterized Edison as a "freethinker".[48] Edison was heavily influenced by Thomas Paine's The Age of Reason.[48] Edison defended Paine's "scientific deism", saying, "He has been called an atheist, but atheist he was not. Paine believed in a supreme intelligence, as representing the idea which other men often express by the name of deity."[48] In an October 2, 1910, interview in the New York Times Magazine, Edison stated:
Nature is what we know. We do not know the gods of religions. And nature is not kind, or merciful, or loving. If God made me — the fabled God of the three qualities of which I spoke: mercy, kindness, love — He also made the fish I catch and eat. And where do His mercy, kindness, and love for that fish come in? No; nature made us — nature did it all — not the gods of the religions.[90]
Edison was accused of being an atheist for those remarks, and although he did not allow himself to be drawn into the controversy publicly, he clarified himself in a private letter:
You have misunderstood the whole article, because you jumped to the conclusion that it denies the existence of God. There is no such denial, what you call God I call Nature, the Supreme intelligence that rules matter. All the article states is that it is doubtful in my opinion if our intelligence or soul or whatever one may call it lives hereafter as an entity or disperses back again from whence it came, scattered amongst the cells of which we are made.[48]
He also stated, "I do not believe in the God of the theologians; but that there is a Supreme Intelligence I do not doubt."[91]
Nonviolence was key to Edison's moral views, and when asked to serve as a naval consultant for World War I, he specified he would work only on defensive weapons and later noted, "I am proud of the fact that I never invented weapons to kill." Edison's philosophy of nonviolence extended to animals as well, about which he stated: "Nonviolence leads to the highest ethics, which is the goal of all evolution. Until we stop harming all other living beings, we are still savages."[92] However, he is also notorious for having electrocuted a number of dogs in 1888, both by direct and alternating current, in an attempt to argue that the former (which he had a vested business interest in promoting) was safer than the latter (favored by his rival George Westinghouse).[93]
Edison's success in promoting direct current as less lethal also led to alternating current being used in the electric chair adopted by New York in 1889 as a supposedly humane execution method. Because Westinghouse was angered by the decision, he funded Eighth Amendment-based appeals for inmates set to die in the electric chair, ultimately resulting in Edison providing the generators which powered early electrocutions and testifying successfully on behalf of the state that electrocution was a painless method of execution.[94]
In 1920, Edison set off a media sensation when he told B. C. Forbes of American Magazine that he was working on a "spirit phone" to allow communication with the dead, a story which other newspapers and magazines repeated.[95] Edison later disclaimed the idea, telling the New York Times in 1926 that "I really had nothing to tell him, but I hated to disappoint him so I thought up this story about communicating with spirits, but it was all a joke."[96]
Thomas Edison was an advocate for monetary reform in the United States. He was ardently opposed to the gold standard and debt-based money. Famously, he was quoted in the New York Times stating "Gold is a relic of Julius Caesar, and interest is an invention of Satan."[97]
In the same article, he expounded upon the absurdity of a monetary system in which the taxpayer of the United States, in need of a loan, be compelled to pay in return perhaps double the principal, or even greater sums, due to interest. His basic point was that if the Government can produce debt-based money, it could equally as well produce money that was a credit to the taxpayer.[97]
He thought at length about the subject of money over 1921 and 1922. In May 1922, he published a proposal, entitled "A Proposed Amendment to the Federal Reserve Banking System".[98] In it, he detailed an explanation of a commodity-backed currency, in which the Federal Reserve would issue interest-free currency to farmers, based on the value of commodities they produced. During a publicity tour that he took with friend and fellow inventor, Henry Ford, he spoke publicly about his desire for monetary reform. For insight, he corresponded with prominent academic and banking professionals. In the end, however, Edison's proposals failed to find support, and were eventually abandoned.[99][100]
The President of the Third French Republic, Jules Grévy, on the recommendation of his Minister of Foreign Affairs Jules Barthélemy-Saint-Hilaire and with the presentations of the Minister of Posts and Telegraphs Louis Cochery, designated Edison with the distinction of an 'Officer of the Legion of Honour' (Légion d'honneur) by decree on November 10, 1881;[101] He also named a Chevalier in 1879, and a Commander in 1889.[102]
In 1887, Edison won the Matteucci Medal. In 1890, he was elected a member of the Royal Swedish Academy of Sciences.
The Philadelphia City Council named Edison the recipient of the John Scott Medal in 1889.[102]
In 1899, Edison was awarded the Edward Longstreth Medal of The Franklin Institute.[103]
He was named an Honorable Consulting Engineer at the Louisiana Purchase Exposition World's fair in 1904.[102]
In 1908, Edison received the American Association of Engineering Societies John Fritz Medal.[102]
In 1915, Edison was awarded Franklin Medal of The Franklin Institute for discoveries contributing to the foundation of industries and the well-being of the human race.[104]
In 1920, The United States Navy department awarded him the Navy Distinguished Service Medal.[102]
In 1923, The American Institute of Electrical Engineers created the Edison Medal and he was its first recipient.[102]
In 1927, he was granted membership in the National Academy of Sciences.[102]
On May 29, 1928, Edison received the Congressional Gold Medal.[102]
In 1983, the United States Congress, pursuant to Senate Joint Resolution 140 (Public Law 97—198), designated February 11, Edison's birthday, as National Inventor's Day.[105]
Life magazine (USA), in a special double issue in 1997, placed Edison first in the list of the "100 Most Important People in the Last 1000 Years", noting that the light bulb he promoted "lit up the world". In the 2005 television series The Greatest American, he was voted by viewers as the fifteenth-greatest.
In 2008, Edison was inducted in the New Jersey Hall of Fame.
In 2010, Edison was honored with a Technical Grammy Award.
In 2011, Edison was inducted into the Entrepreneur Walk of Fame, and named a Great Floridian by the Florida Governor and Cabinet.[106]
Several places have been named after Edison, most notably the town of Edison, New Jersey. Thomas Edison State College, a nationally known college for adult learners, is in Trenton, New Jersey. Two community colleges are named for him: Edison State College in Fort Myers, Florida, and Edison Community College in Piqua, Ohio.[107] There are numerous high schools named after Edison (see Edison High School) and other schools including Thomas A. Edison Middle School.
In 1883, the City Hotel in Sunbury, Pennsylvania was the first building to be lit with Edison's three-wire system. The hotel was renamed The Hotel Edison upon Edison's return to the City on 1922.[108]
Lake Thomas A Edison in California was named after Edison to mark the 75th anniversary of the incandescent light bulb.[109]
Edison was on hand to turn on the lights at the Hotel Edison in New York City when it opened in 1931.[110]
Three bridges around the United States have been named in Edison's honor: the Edison Bridge in New Jersey,[111] the Edison Bridge in Florida,[112] and the Edison Bridge in Ohio.[113]
In space, his name is commemorated in asteroid 742 Edisona.
In West Orange, New Jersey, the 13.5 acres (5.5 hectares) Glenmont estate is maintained and operated by the National Park Service as the Edison National Historic Site, as is his nearby laboratory and workshops including the reconstructed Black Maria- the world's first movie studio.[114] The Thomas Alva Edison Memorial Tower and Museum is in the town of Edison, New Jersey.[115] In Beaumont, Texas, there is an Edison Museum, though Edison never visited there.[116] The Port Huron Museum, in Port Huron, Michigan, restored the original depot that Thomas Edison worked out of as a young newsbutcher. The depot has been named the Thomas Edison Depot Museum.[117] The town has many Edison historical landmarks, including the graves of Edison's parents, and a monument along the St. Clair River. Edison's influence can be seen throughout this city of 32,000.
In Detroit, the Edison Memorial Fountain in Grand Circus Park was created to honor his achievements. The limestone fountain was dedicated October 21, 1929, the fiftieth anniversary of the creation of the lightbulb.[118] On the same night, The Edison Institute was dedicated in nearby Dearborn.
The Edison Medal was created on February 11, 1904, by a group of Edison's friends and associates. Four years later the American Institute of Electrical Engineers (AIEE), later IEEE, entered into an agreement with the group to present the medal as its highest award. The first medal was presented in 1909 to Elihu Thomson. It is the oldest award in the area of electrical and electronics engineering, and is presented annually "for a career of meritorious achievement in electrical science, electrical engineering or the electrical arts."
In the Netherlands, the major music awards are named the Edison Award after him. The award is an annual Dutch music prize, awarded for outstanding achievements in the music industry, and is one of the oldest music awards in the world, having been presented since 1960.
The American Society of Mechanical Engineers concedes the Thomas A. Edison Patent Award to individual patents since 2000.[119]
The United States Navy named the USS Edison (DD-439), a Gleaves class destroyer, in his honor in 1940. The ship was decommissioned a few months after the end of World War II. In 1962, the Navy commissioned USS Thomas A. Edison (SSBN-610), a fleet ballistic missile nuclear-powered submarine.[citation needed]
Thomas Edison has appeared in popular culture as a character in novels, films, comics and video games. His prolific inventing helped make him an icon and he has made appearances in popular culture during his lifetime down to the present day. Edison is also portrayed in popular culture as an adversary of Nikola Tesla.
On February 11, 2011, on Thomas Edison's 164th birthday, Google's homepage featured an animated Google Doodle commemorating his many inventions. When the cursor was hovered over the doodle, a series of mechanisms seemed to move, causing a lightbulb to glow.[120]
Other inventors and businessmen
The will of Thomas A. Edison, filed in Newark last Thursday, which leaves the bulk of the inventor's $12 million estate to the sons of his second wife, was attacked as unfair yesterday by William L. Edison, second son of the first wife, who announced at the same time that he would sue to break it.
West Orange, New Jersey, Sunday, October 18, 1931. Thomas Alva Edison died at 3:24 o'clock this morning at his home, Glenmont, in the Llewellyn Park section of this city. The great inventor, the fruits of whose genius so magically transformed the everyday world, was 84 years and 8 months old.
Thomas A. Edison in the following interview for the first time speaks to the public on the vital subjects of the human soul and immortality. It will be bound to be a most fascinating, an amazing statement, from one of the most notable and interesting men of the age ... Nature is what we know. We do not know the gods of religions. And nature is not kind, or merciful, or loving. If God made me — the fabled God of the three qualities of which I spoke: mercy, kindness, love — He also made the fish I catch and eat. And where do His mercy, kindness, and love for that fish come in? No; nature made us — nature did it all — not the gods of the religions.
On January 1, 1889, the world's first electrical execution law went into full effect. Westinghouse protested the decision and refused to sell any AC generators directly to prison authorities. Thomas Edison and Harold Brown provided the AC generators needed for the first working electric chairs. George Westinghouse funded the appeals for the first prisoners sentenced to death by electrocution, made on the grounds that "electrocution was cruel and unusual punishment." Edison and Brown both testified for the state that execution was a quick and painless form of death and the State of New York won the appeals.
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Fight For Your MoneyA Letter From DavidDAVID BACH'S BATTLE PLAN WILL PUT THOUSANDS OF DOLLARS BACK IN YOUR POCKETS -- WHERE IT BELONGSA WAR FOR YOUR MONEY IS RAGINGRight now, whether you realize it or not, we're in an ongoing battle with giant corporations and economic institutions whose only goal is to separate us from our hard earned paychecks. Airlines, banks, cell phone providers, insurance companies -- even hospitals have made it their priority to earn more every year at our expense. Their misleading come ons, withheld information, hidden fees, extra points, late charges, escalating rates and more are costing you thousands. We consumers have been losing the battle because THEY are better equipped to take our money than WE are to keep it. Until now. ARE YOU READY TO FIGHT BACK?If getting ripped off makes you mad -- and it should -- I encourage you to join our movement of smart, empowered consumers who are using the strategies and tools found in this book to fight back. Spend a few hours with me as your coach and together let's FIGHT for your money and WIN. - David Bach Latest News & TweetsDavid on Twitter (Follow)David Bach In The News
Join Our Movement of Smart, Empowered Consumers on FacebookRead FOUR free chapter excerpts of Fight for Your Money. Join our Billion Dollar Savings Challenge. Be part of our community! |

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- Northern New York Newspapers
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A Fort Drum resident was charged by Jefferson County sheriffs deputies with second-degree identity theft, forgery and criminal impersonation after he allegedly opened up a line of credit in another persons name.
Deputies said Elijah O. Williams, 20, of 10602 5th Armored Division Drive, bought an Apple MacBook computer, iPod, headphones and computer protective case, valued at a total of $1,937.23, with the credit line.
Charged at 1 p.m. Friday, he was released to the custody of Fort Drum military police and given an appearance ticket for LeRay Town Court.


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The shrine of knowledge.
Keen Intellect
A selection of articles related to keen intellect.
Original articles from our library related to the Keen Intellect. See Table of Contents for further available material (downloadable resources) on Keen Intellect.
- Hod & Netzach
- Just as the previous pairs of Sephiroth, (Binah - Chokmah, Chessed - Gedulah), needed to be explained together to be fully understood, (Binah depends on that of Chokmah, and Chessed relies on Geburah, visa versa), so it is with Hod and Netzach. Hod is form...
Magick >> Qabalah
- The True Nature of Intelligence
- The first step taken by the true intellectual toward personal enlightenment, is to understand that there exists something worthwhile to learn. For them the learning process begins in the study of the opinions of others, an activity they ultimately reject...
Religion & Philosophy >> Philosophy
- Teiresias, the Blind Seer
- This may not at all sound as it could have something to do with Libra, but the story goes like this: Teiresias one day happens into the sacred grove of Hera, where he comes upon two snakes coupling in the grass. The moment is ill chosen, for it shows that...
Deities & Heros >> Greek
- Yellow: Correspondences
- Definition: Creativity, thought, intellect, sun energy Magickal Powers: Bring new ideas, new environments, talking, philosophy Element: Air Direction: East Gender: Male Season: Summer Stage of Life: Youth, Maturity Candle Magick: Sun, intelligence,...
Symbology >> Colorology
- The Skeptical Witch
- The Choir finished the last notes of the worship service. I sit down in unison with 3000 other people preparing to hear the word of the Lord from Apostle Benjamin. The worship service does not touch me. The words of the Apostle are empty for me. My mind is in...
Paganism & Wicca >> Daily Life
- Basics of Magick: The Use of Color in Magick
- White | Silver | Grey | Pink | Red | Purple | Brown | Blue | Green | Yellow | Gold | Black In magick, colors represent certain energies, goals, people and non-physical beings, such as deities or spiritual forces. For this reason, you should include candles,...
Symbology >> Colorology
Keen Intellect is described in multiple online sources, as addition to our editors' articles, see section below for printable documents, Keen Intellect books and related discussion.
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- www.nap.edu
- www.thewinnetkaclub.org
- "He is also highly regarded for his keen intellect and always having the courage of his convictions. He will be greatly missed by all the justices and court staff.
- www.courts.ca.gov
- Client Patent Portfolio Scores High on Quality Test
- significantly to the efforts, skills and keen intellect of the partners of Fincham Downs.
- finchamdowns.com
- From Out of the Primordial Soup: A Brief History of Anaesthesia
- He was accepted with the handsome bursary of ten pounds per year. At Medical school.
- priory.com
Suggested News Resources
- Civil suit against Strauss-Kahn moving forward
- Defense attorney Paul Callan said in an email that McKeon has a "keen intellect, the instincts of a street fighter & an abundance of political savvy.
- Jerome J. Shestack, 88, lawyer and human-rights leader | Philadelphia Inquirer
- "He exemplified the ideals of keen intellect, personal character, and professional commitment.
- Evans, 71, served on federal appeals court
- "With his rare combination of an absolute keen intellect and his abundant practical wisdom, he was able to pick up on the human side and to understand the human side of the law," Sykes said.
- Fox News Rides GOP Presidential Debate To Enter Top Five Cable Networks Last Week
- Yes… such an astute observation I commend your keen intellect! "Resist we much, we must, and we will much…." Now that comes from a real News source.
Suggested Web Resources
- intellect - definition of intellect by the Free Online Dictionary
- Noun, 1. intellect - knowledge and intellectual ability; "he reads to improve his mind"; "he has a keen intellect".
- www.thefreedictionary.com
- keen - definition of keen by the Free Online Dictionary, Thesaurus
- www.thefreedictionary.com
- meaning - What does "keen" in "keen intellect" mean? - English
- Aug 22, 2010 up vote 2 down vote favorite. 1. share [fb] share [tw] share [in].
- english.stackexchange.com
- Lawyer, budget-cutter and executive displayed keen intellect
- Dec 8, 2010 James T.
- www.washingtonpost.com
- It Takes A Keen Intellect To Play Chess, Mr. Powers Sound Clip and
- It Takes a Keen Intellect to Play Chess, Mr. Powers Sound Clip and Quote. Ivana Humpalot sits down with Austin Powers to play a game of chess.
- www.hark.com
Great care has been taken to prepare the information on this page. Elements of the content come from factual and lexical knowledge databases, realmagick.com library and third-party sources. We appreciate your suggestions and comments on further improvements of the site.


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Poole, Thomas and Shah, Sangeeta (2009) The impact of the Human Rights Act on the House of Lords. Public Law (April). pp. 347-371. ISSN 0033-3565
Full text not available from this repository.Abstract
Reports on a survey analysing the impact of the Human Rights Act 1998 on cases heard by the House of Lords between 1994 and 2007. Outlines the background to the research, the methodology adopted and the main findings on whether the House showed a greater willingness after the Act's commencement to grant leave to appeal in cases raising human rights issues, the number of cases in which human rights arguments were advanced, the success rate of such arguments and the human rights questions raised in devolution cases before the Privy Council.
Item Type: | Article |
Official URL: | http://www.sweetandmaxwell.co.uk/Catalogue/Product... |
Additional Information: | © 2009 Sweet & Maxwell and its Contributors |
Library of Congress subject classification: | K Law > K Law (General) |
Sets: | Departments > Law |
Date Deposited: | 23 Jun 2009 11:51 |
URL: | http://eprints.lse.ac.uk/24282/ |
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The Library
Animal-based measures for the assessment of welfare state of dairy cattle, pigs and laying hens: Consensus of expert opinion
UNSPECIFIED. (2003) Animal-based measures for the assessment of welfare state of dairy cattle, pigs and laying hens: Consensus of expert opinion. ANIMAL WELFARE, 12 (2). pp. 205-217. ISSN 0962-7286
Full text not available from this repository.Abstract
A Delphi technique was used to gather the opinions of animal welfare experts on the most appropriate measures for welfare assessment of farm animals. The experts were asked to consider measures that were directed towards the animal (animal-based), rather than measurement of their environment. This systematic approach was designed to achieve a degree of consensus of opinion between a large number of experts. Two rounds of postal questionnaires were targeted at people with expertise in one or more of the species of interest. The respondents suggested measures based upon observations of health status, behaviour, and examination of records. These measures reflect the animal's welfare state in other words, how the animal is coping within the environment and husbandry system in which it lives. The measures for cattle, pigs and laying hens were categorised into 22, 23 and 28 aspects, respectively, with the highest ranking of importance being given to observation of lameness in dairy cattle and pigs and to observation of feather condition in laying hens. This Delphi study was the basis for the development of a series of protocols to assess the welfare state of dairy cattle, pigs and laying hens.
Item Type: | Journal Article |
Subjects: | S Agriculture > SF Animal culture Q Science > QL Zoology |
Journal or Publication Title: | ANIMAL WELFARE |
Publisher: | UNIV FEDERATION ANIMAL WELFARE |
Official Date: | May 2003 |
Volume: | 12 |
Number: | 2 |
Number of Pages: | 13 |
Page Range: | pp. 205-217 |
Publication Status: | Published |
URI: | http://wrap.warwick.ac.uk/id/eprint/9808 |
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Thanks for the responses. The 7hp on the Cal sounds great. I recognize that the stated 30hp of the A4 isn't quite right but it's still allot of engine for that boat, and it certainly is large. I talked to Stanley at Beta this morning, was curious about their engines. I was interested to hear that the Beta is a marine version Kubota. My impression was that 'Phasor' was their marine diesel. Anyway, at about 7k USD for the 14hp, I'm going to start looking at the reman and used engines first. And my A4 is recently rebuilt and in excellent shape so I may take advantage of those links, thanks. Nothing wrong with the engine, just my own thing about having a gasoline engine three feet away from where I'm cooking.
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Biker rallies, rodeos, and other loud gatherings in the American South. Watch out for the flaming torches.
NFL star Randy Moss is now a high school coach. A Vikings fan explains how watching one childhood hero move on with his life helps him say goodbye to another.
Mainstream country music is dominated by bros singing about girls in cutoffs and drinking tequila. But some female country artists are ready to exchange fire.
Tobacco farmers, churchgoers, and signs of rapid growth crop up like kudzu along North Carolina's Highway 15-501, aka Tobacco Road.
Evidence of diversity emerging in Northeast Tennessee, historically one of the United States' most conservative, homogeneous regions.
Passing the summer days in North Carolina's low country often meant sitting on the porch with Grandpa and his radio. Today, it doesn't take much to go back there.
Lincoln's speech at Gettysburg was short: only three minutes long, following a moving, two-hour performance by famed orator Edward Everett. It also was nearly meaningless.
A special Fourth of July edition of our series where an editor randomly calls people in small towns around America to see what's happening.
For residents of Patsy Cline's hometown of Winchester, Va., the struggle over how to remember the famous country singer begins with deciding what sort of a legacy she left—and whether they want it.
Our man in Boston sits down for a frank accounting with Tony Horwitz, author of beloved works like Confederates in the Attic: Dispatches From the Unfinished Civil War. Here they chat about his new book on John Brown—still a divisive figure in America, particularly in these days of terrorism—and the hazards of politicians reading too much.
Our man in Boston talks with writer Ron Rash about his latest book, America's great regional voices, the high percentage of readers in New Zealand and Australia, and the misery that accompanies putting a novel together, where it's rather more fun to stick pencils in your eyes.
Continuing our series of randomly calling people around the U.S. to find out what's going on in their towns, this time we focus on the Olympics—how do folks who come from the same communities as America's Olympians feel about their star athletes?


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Please use this identifier to cite or link to this item:
Title: | Entrainment to extinction of physiological tremor by spindle afferent input |
Authors: | Cathers, Ian O'Dwyer, Nicholas Neilson, Peter Discipline of Exercise and Sport Science Faculty of Health Sciences |
Keywords: | stretch reflex tremor coupled oscillators neural modeling wrist electromyography |
Issue Date: | 2006 |
Publisher: | Springer Verlag |
Citation: | Ian Cathers, Nicholas O'Dwyer, Peter Neilson (2006) Entrainment to extinction of physiological tremor by spindle afferent input. Experimental Brain Research, Volume 171, Number 2 / May, 2006. Pages 194-203. The original publication is available at www.springerlink.com. |
Abstract: | In this study the systematic modulation of wrist flexor muscle activity by imposed joint movement was examined. Ten subjects maintained a constant contraction level (25% of maximum; trial duration: 20 s) in flexor carpi radialis while their wrists were perturbed with 50 different quasi-sinusoidal signals (frequency range: 0.5 - 9.5 Hz; amplitude: 0.3° - 4.2°). Frequency spectra of wrist position and the rectified and filtered electromyogram (EMG) were determined. The muscle activity was only weakly entrained to imposed movements of small amplitude and low frequency, as shown by a small peak in the EMG spectrum at the frequency of movement, while the most prominent peak in the spectrum was between 9 - 15 Hz, corresponding to the frequency range of physiological tremor. The entrainment of muscle activity increased markedly as the amplitude and frequency of the imposed movement increased, to the point of saturation of modulation and harmonic peaks in the spectrum. In parallel with this increase in entrainment, the 9 - 15 Hz tremor peak was progressively extinguished. The results are consistent with a coupled oscillator model in which the central oscillatory source(s) of tremor became fully entrained to the imposed movement at the highest amplitudes and frequencies. Such coupling depends on communication between the external forcing oscillator and the central oscillator(s), the Ia afferent signal from the imposed movement being the most likely candidate to provide the entraining signal for the central oscillator(s). |
URI: | http://hdl.handle.net/2123/3540 |
Department/Unit/Centre: | Discipline of Exercise and Sport Science Faculty of Health Sciences |
Type of Work: | Article |
Appears in Collections: | Research Papers and Publications. Discipline of Exercise and Sport Science |
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