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Thomas Alva Edison

1847 - 1931


Inventor of almost Everything

The story of Edison on the 150th anniversary of his birth. Edison, inventor and genius, whose development of a practical electric light bulb, electric generating system, sound-recording device, carbon tele-phone transmitter and motion picture projector had pro-found effects on the shaping of modern society.

Thomas Edison was born in Milan, Ohio, on February 11, 1847. He attended school for only three months, in Port Huron, Michigan and his further education came from his mother. She had the talent to make learning inter-esting but it was not long before the young Thomas was asking questions his mother could not answer.

When he was 12 years old he began selling newspapers and fruit on the Grand Trunk Railway, devoting his spare time mainly to experimentation with printing presses and electrical, chemical and mechanical apparatus. In 1862 he published a weekly, known as the Grand Trunk Herald, printing it in a freight car that also served as his laboratory.

One fateful day he was experimenting in the moving freight car with phosphorus, a chemical that flares up very easily. Pretty soon the car was on fire and, although the fire was soon put out, the guard was sufficiently displeased that he put Edison off the train at the next station, along with all this chemicals.

For saving the life of a station official's child from being run over by a train, he was rewarded by being taught telegraphy. While working as a telegraph operator, he made his first important invention, a telegraphic repeating instrument that enabled messages to be transmitted auto-matically over a second line without the presence of an operator.

Edison next secured employment in Boston and devoted all his spare time there to research. He invented a vote recorder that, although possessing many merits, was not sufficiently practical to warrant its adoption. The rejection of this invention by the US Government was to have a major effect on Edison's future research. He learnt to find out if a thing was needed before he set about inventing it.

He devised and partly completed a stock-quotation printer. Later, while employed by the Gold and Stock Telegraph Company of New York City he greatly improved their apparatus and service. By the sale of telegraphic appliances, Edison earned $40,000, and with this money he established his own laboratory in 1876.

This laboratory was at Menlo Park in rural New Jersey. This would be the centre of operations for a very long time as Edison surrounded himself with a hand-picked team of "scientific men". The second floor of the laboratory building was equipped with 2,500 bottles of chemicals and a massive pipe organ.

One of the first creations to come out of Menlo Park was "An Improvement in Autographic Printing", or electric pen, a prototype for document reproduction. This machine cut stencils by hand using a powered needle. Edison eventually sold the patent to A. B. Dick, pioneer of the mimeograph.

Meanwhile Edison had embarked on the most consuming obsession of his career. He purchased a 2,500 acre site in Sparta, New Jersey, and set up a mining camp. He would spend much of the next decade living amidst dust and grime, determined to extract and refine magnetic ore from these mountains. A great deal of his genius went into designing magnetic devices to transfer the ore and to separate it in the refining process.

He devised an automatic telegraph system that made possible a greater speed and range of transmission. His crowning achievement in telegraphy was his invention of machines that made possible simultaneous transmission of several messages on one line and thus greatly increased the usefulness of existing telegraph lines.

Two of Edison's greatest inventions were in the area of the telephone, which had recently been invented by the American physicist and inventor Alexander Graham Bell. Edison had been investigating the possibility of the telephone for some time before Bell lodged his patent and he had early in 1876 sent the Patent Office a caveat which said he was working on the subject. It was not until January 1977 that he began to experiment with the varying resistance of carbon under differing pressures.

Finally he made a small button from lampblack taken from a smoking petroleum lamp.

In Bell's telephone it was the human voice which actually generated the necessary weak electric current (sound powered). In Edison's telephone, the human voice was used to open or close a valve which regulated the electric current.

But there was another feature of the Edison transmitter just as important in practical terms. In Bell's system it was the original weak currents themselves which were transmitted along the wire to the other telephone. In Edison's, the battery current was passed through the primary of an induction coil, the secondary coil of which was able to produce corresponding impulses of enormously higher potential for sending along the wire to the receiver. This the range of the telephone was increased in one single bound from a few miles to hundreds.

Edison's new transmitter was first tested over a 106 mile line between New York and Philadelphia. The patent was filed in April 1877 but it is symptomatic of the turbulent conditions of the time that the patent was not granted until May 1892.

Western Union snapped up Edison's transmitter which was superior to Bell's. However the Bell camp had the superior receiver and had patents to protect it. Thus, there existed a situation where one camp had a good transmitter and no receiver whilst the other camp had a good receiver and an inferior transmitter.

Edison set his mind to the problem and, within three months, came up with the chalk receiver. In this device, a chalk cylinder revolved either by hand or by a motor and was pressed upon by a spring attached to a receiving diaphragm. The varying electrical current emerging from the transmitter controlled the amount of friction between the chalk and the spring, and this in turn produced vibrations of the diaphragm which repeated the sounds made into the transmitter. The new device not only obviated any use of the Bell patent but reception with it was louder.

The carbon transmitter was clearly Edison's greatest contribution to telephony but the chalk receiver should not be forgotten as it opened the way for competition in the industry and led to a far better telephone instrument to be available for the public to use. It is interesting to note some confusion between Edison's two telephony inventions. The 1984 edition of the World Book Encyclopedia shows a picture of the chalk receiver with the following caption: "Edison's work on the carbon telephone transmitter helped pave the way for the modern telephone. The early transmitter shown here used chalk instead of carbon granules".

In 1877 Edison announced his invention of a phonograph by which sound could be recorded mechanically on a tinfoil cylinder. It is the phonograph which will be remembered as the first of Edison's greatest inventions.

Two years later he exhibited publicly his incandescent electric light bulb, his second important invention and the one requiring the most careful research and experimentation to perfect. This new light was a remarkable success; Edison promptly occupied himself with the improvement of the bulbs and of the dynamos for generating the necessary electric current.

In 1882 he developed and installed the world's first large central electric-power station, located in New York City. His use of direct current, however, later lost out to the alternating-current system developed by the American inventors Nikola Tesla and George Westinghouse.

His desire to see his inventions benefit children was satisfied by his invention of a talking doll. The hollow innards contained a miniature phonograph cylinder on a screw thread shaft connected to a crank protruding from the doll's back. There was just enough space on each cylinder for the first verse of "Mary Had a Little Lamb", "Jack and Jill" or "Little Bo Peep". Alas, the project was short lived as the delicate mechanism seldom withstood the delivery process and many disappointed children received a doll that would not talk.

In 1887 Edison moved his laboratory from Menlo Park, New Jersey, to West Orange, New Jersey, where he constructed a large laboratory for experimentation and research. In 1888 he invented the kinetoscope, the first machine to produce motion pictures by a rapid succession of individual views.

Among his later noteworthy inventions was the Edison storage battery (an alkaline, nickel-iron storage battery), the result of many thousands of experiments. The battery was extremely rugged and had a high electrical capacity per unit of weight. He also developed a phonograph in which the sound was impressed on a disk instead of a cylinder. This phonograph had a diamond needle and other improved features. By synchronising his phonograph and kinetoscope, he produced, in 1913, the first talking moving pictures.

His other discoveries include a storage battery for use in an electric car, a house made almost entirely of concrete, a microtasimeter (used for the detection of minute changes in temperature), and a wireless telegraphic method for communicating with moving trains.

Following the outbreak of World War I, Edison designed, built, and operated plants for the manufacture of benzene, carbolic acid, and aniline derivatives. In 1915 he was appointed president of the U.S. Navy Consulting Board, an inventors' think tank. He was often to be found on board naval ships developing defensive "peace insurance" ideas "to protect our boys at sea" against dreaded submarines. He also followed his electric car research to improve batteries used for submarine propulsion.

His later work consisted mainly of improving and perfecting previous inventions. Altogether, Edison patented more than 1000 inventions. He was a technologist rather than a scientist, adding little to original scientific knowledge. In 1883, however, he did observe the flow of electrons from a heated filament-the so-called Edison effect-whose profound implications for modern electronics were not understood until several years later.

In 1878 Edison was appointed Chevalier of the Legion of Honour of France and in 1889 was made Commander of the Legion of Honour. In 1892 he was awarded the Albert Medal of the Society of Arts of Great Britain and in 1928 received the Congressional Gold Medal "for development and application of inventions that have revolutionised civilisation in the last century."

Edison did not believe in exercise. He chewed tobacco continuously and smoked several cigars a day. For many years his only foods were milk and an occasional glass of orange juice. Yet ulcers, diabetes and Bright's disease (kidney disease) could not dim the persistent lustre in his gaze. Toward the end, he emerged from a coma, looked at his wife, Mina, and said "It is very beautiful over there."

From June 1931, Edison's health deteriorated considerably, lapsing in and out of comas. Many times he was only given a few days to live but each time he fought back. Early in October the Pope sent the first of two messages asking for news of his health and the 4th October was set aside as a day of prayer for his recovery.

Edison died in West Orange on October 18, 1931. His body lay in state in his laboratory at West Orange and suggestions for a dramatic gesture marking his achievements poured into his home and into the White House.

At 6.59pm Pacific time on 21 October, as the sun set off California, and in Denver, where it was 7.59pm mountain time, the lights went out. It was 8.59pm in Chicago and here the elevated trains and the street-cars stopped for one minute, the lights were extinguished in the city, and all the Mississippi Valley was in darkness. It was 9.59pm in New York and all but essential street lights were switched off, the lights on Broadway were dimmed and the torch on the Statue of Liberty was extinguished. This was the only time in history that such a tribute was paid to one man.

For one minute America was almost back to the age of kerosene and gas lamps. Then, from coast to coast, electric light blazed out again.

Edison's birthplace in Milan, Ohio, was restored as part of a national centennial observance in 1947. In July 1956, President Dwight D. Eisenhower proclaimed the research laboratory at West Orange as a national monument. His home in West Orange became part of the monument in 1959 and in 1962, both were redesignated as the Edison National Historic Site.

Ref: Encarta 96; World Book Encyclopedia, Vol 6, 1984; "The Story of Electricity", John Munro, 1896; "Edison, The Man Who Made The Future" by Ronald W. Clark, 1977; Richard's Topical Encyclopedia, Vol. 13, 1955.



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