FEATURE ARTICLE KRISHNA MURTY KOMMAJOSYULA Light on electric Thomas Edison light! with his lamp TheTh journey j of f electricl t i lightli ht hash beenb fascinating.f Thomas Alva Edison later described he and his associate wrestled with the task of placing the carbonized cotton in the fi rst electric bulb: “All night Bachelor, my assistant, worked beside me. The next day and the next night again, and at the end of that time we had produced one carbon out of an entire spool of Clarke’s thread. Having HE inventor was seated in his made it, it was necessary to take it to laboratory alone one evening, the glass-blower’s house. With the Tgloomy over his thousand- utmost precaution Bachelor took up the and-one disappointments. Though not precious carbon, and I marched after crushed in spirit, the frustration was him, as if guarding a mighty treasure. visible. He had worked with every To our consternation, just as we reached known material to make a workable the glass-blower’s bench the wretched fi lament for his electric bulb… and had carbon broke. We turned back to the failed. main laboratory and set to work again. Absentmindedly, his right hand It was late in the afternoon before we The incandescent picked up a little lampblack mixed had produced another carbon, which light bulb with tar lying on the table, left over was again broken by a jeweller’s from his earlier experiment on a screw-driver falling against it. But we telephone transmitter. He began rolling turned back again, and before night the plant imaginable. He even contacted it between his fi nger and thumb… and carbon was completed and inserted in biologists who sent him plant fi bres while getting up, as he tried to clean his the lamp. The bulb was exhausted of air from faraway places. fi ngers he saw the thin thread. Soon his and sealed, the current turned on, and It seems, on a certain hot day in brilliant mind had an idea. Why not use the sight we had so long desired to see 1879, as Edison was fanning himself a fi lament for an incandescent lamp? met our eyes.” with a foldable oriental fan from Japan, That was the beginning of the Edison and Bachelor watched a fi ne bamboo piece got unwound from incandescent lamp that has lighted the electric lamp for forty-fi ve hours it. Inquisitive as he was, he carbonized up our homes for over hundred years until the light vanished. The weary the piece and tested it as a fi lament. He but now may soon be relegated to the men congratulated each other. Edison sent assistants to Japan to get the right museums. tested the carbonized fi laments of every type of bamboo. 37 SCIENCE REPORTER April 2017 The Savoy Theatre, London, was the fi rst public building to be lit up entirely by electricity Edison thus came to be known as A research in 2007 also concluded that patent litigation the courts decided in the inventor of electric light. Scientists the Goebel-Defense was fraudulent. Edison’s favour in 1892 and forced around the world worked on the On 3 August 1874, Henry Westinghouse to stop production. incandescent lamp, improving their Woodward, a medical student and Similarly, William Sawyer extremely short lifespans, reducing cost Mathew Evans received a Canadian developed a lighting system in 1877 and and improving effi ciency. patent for an electric light bulb. Their received patents with Albon Man. They Edison could outdo others because light bulb was a glass tube fi lled with soon formed Sawyer & Man Electric of his astute business sense, innovation inert nitrogen and had carbon fi lament. Co. Westinghouse contracted him to in developing an effective incandescent They fi led for a patent in the United light up the Chicago World’s Fair material, and availability of better States prior to Edison’s patent but in 1893. Sawyer successfully fought vacuum pumps and viable electrical failed to commercialize it. Shrewd against Edison. Westinghouse bought systems. But then, Edison was not the businessman that he was, Edison rights to the Sawyer-Man patents and fi rst. purchased the patent before he obtained started making lamps based on those A British astronomer and chemist, his own patent. patents. De La Rue created the light bulb in 1820 In 1874, Alexander Lodygin In the late 1870’s, high school by passing an electric current through received a Russian patent for the teachers, Elihu Thomson and Edwin a platinum coil in a vacuum tube. The incandescent light bulb. He later moved Houston began experimenting and cost of the platinum made it impractical to the US and demonstrated a light bulb for commercial production. In 1893, with a molybdenum fi lament at the newspapers reported that Henry Goebel World’s Fair in Paris in 1900. had developed incandescent light bulbs “If you want to succeed, get some 25 years earlier comparable to those enemies,” Edison was quoted as saying invented by Edison in 1879. But this in the Ladies Home Journal, April German scientist who migrated to the 1898. When he could not fi ght with his US did not apply for a patent. enemy, he made friends with them. But In May 1893, the Edison one up was Hiram Maxim who hired Electric Light Co. sued competitive Ludwig Boehm, Edison’s glassblower manufacturers for infringing their patent away from Menlo Park and quickly rights. However, the defence of these produced a lamp with a high-resistance companies claimed that Edison’s patent fi lament in 1880. Maxim lamps were was void because of the same invention made by his United States Electric by Goebel 25 years earlier. But judges Lighting Company for several years of four courts were convinced that there until the company was purchased by was no proof for the claimed invention. George Westinghouse in 1888. In a 38 SCIENCE REPORTER April 2017 Then in 1904, insanely great but relatively unknown Charles P. Steinmetz replaced the carbon electrode with magnetite, a type of iron ore. The lamp life increased to 600 hours from 125 hours. But later, the Xenon short- arc lamp extinguished the carbon arc lamp. Another serious competitor to the incandescent bulb then was the Nernst lamp. Nernst Lamp effectively solved the fi lament bulb problems, emitted a natural light close to day light and was about twice as effi cient. It used a small ceramic rod, not electrically conductive at room temperature. It was heated to incandescence by a separate heater fi lament. When its resistance dropped, Nernst lamp a switch would cut off power to the Xenon arc lamp heater and all the current would fl ow through the glower. The ceramic did not oxidise like metal, and the glass established the American Electric States patent rights to the Brush Electric enclosure was dispensed with. Apart Company, which was renamed the Company in June 1882, which later from domestic illumination, Nernst Thomson-Houston Electric Company. merged into the Thomson-Houston lamps were made use of in fax systems, In 1886, this company purchased the Electric Company. for ophthalmology, for projection and Sawyer & Man Electric Company By 1890, Edison with his merged in microscopy. Walther Nernst won and began making incandescent lamps companies, Thomson-Houston, and the 1920 Nobel Prize in Chemistry. under the Sawyer-Man patents. Westinghouse were the “Big 3” of the Nobel Laureate, Irving Langmuir, Joseph Wilson Swan (1828- American lighting industry. In 1892, J. who studied under Nernst, helped him 1914), a physicist and chemist born in Pierpont Morgan engineered a merger develop the Nernst lamp. Sunderland, England created a “light between the Edison and Thomson- Industry giants had to double bulb” by enclosing carbonized paper Houston and General Electric was born. up their researches to face the threat fi lament in an evacuated glass bulb in Lewis Howard Latimer patented from Nernst lamps, then a craze with 1850. Though unsuccessful initially, a carbon fi lament with longer life. He the fashionable high and powerful Swan returned to his experiments as also created the threaded socket that mighty. Werner von Bolton in better vacuum pumps became available. allows a light bulb to fi t into the fi xture. Germany developed the tantalum He failed in his fi rst public attempt to Edison eventually purchased the patent fi lament with higher effi ciency and light up his incandescent carbon lamp at and hired Latimer in 1884. greater brightness. Siemens and a lecture for the Newcastle upon Tyne Humphry Davy and Frederick Halske Company marketed these bulbs Chemical Society on 18 December de Moleyns also tried their hand at successfully. Sensing a major threat, 1878. However, on 17 January 1879 creating an incandescent light. In the General Electric formed research labs he was successful and by 1880, he early 1800s, Sir Humphry Davy used and giants like Willis Whitney, William produced a 16-watt bulb that could last charcoal sticks and batteries to make D. Coolidge and Irving Langmuir were for 1500 hours. His house, in Gates the fi rst experimental arc lamp. The roped in. In 1903, Willis Whitney Head, England was lit up by electric two carbon rods must have just enough invented a metal-coated carbon fi lament light for the fi rst time in the world. gap to get the proper arc. A number with an improved effi ciency of 25%. Swan obtained a British patent of experiments were carried out to This fi lament would not blacken the and took Edison to court for patent improve the carbon rod life, adjustment inside of a light bulb and was used in infringement.