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Invention of the TelegraphThe Growth of an Idea0317500The laying of the cable---John and Jonathan joining hands, ca. 1858.Prints and Photographs Division. Reproduction Number: LC-USZ62-5309The idea of using electricity to communicate over distance is said to have occurred to Morse during a conversation aboard ship when he was returning from Europe in 1832. Michael Faraday's recently invented electromagnet was much discussed by the ship's passengers, and when Morse came to understand how it worked, he speculated that it might be possible to send a coded message over a wire. While a student at Yale College years before, he had written his parents a?letter?about how interesting he found the lectures on electricity. Despite what he had learned at Yale, Morse found when he began to develop his idea that he had little real understanding of the nature of electricity, and after sporadic attempts to work with batteries, magnets, and wires, he finally turned for help to a colleague at the University of the City of New York, Leonard D. Gale.Gale was a professor of chemistry and familiar with the electrical work of Princeton's Joseph Henry, a true pioneer in the new field. Well before Morse had his shipboard idea about a telegraph, Henry rang a bell at a distance by opening and closing an electric circuit. In 1831, he had published an article, of which Morse was unaware, that contained details suggesting the idea of an electric telegraph. Gale's help and his knowledge of this article proved crucial to Morse's telegraph system because Gale not only pointed out flaws in the system but showed Morse how he could regularly boost the strength of a signal and overcome the distance problems he had encountered by using a relay system Henry had invented. Henry's experiments, Gale's assistance, and, soon after, hiring the young technician Alfred Vail were keys to Morse's success.Obstacles and OpportunitiesBy December 1837, Morse had enough confidence in his new system to apply for the federal government's appropriation, and during the next year he conducted demonstrations of his telegraph both in New York and Washington.However, when the economic disaster known as the Panic of 1837 took hold of the nation and caused a long depression, Morse was forced to wait for better times. It was during this period that Morse visited Europe again and tried not only to secure patent protection overseas but to examine competing telegraph systems in England. After meeting Charles Wheatstone, the inventor of one such electric telegraph system, Morse realized that although his main competitor had built an ingenious mechanism, his own system was far simpler, more efficient, and easier to use.Morse felt very confident. His system used an automatic sender consisting of a plate with long and short metal bars representing the Morse code equivalent of the alphabet and numbers. The operator slid a pointer connected to a battery and the sending wire across the bars, and immediately the appropriate dots and dashes were sent over the line. The receiver used an electromagnet with a stylus (a pen-like instrument) on the end of an arm. When the magnet operated, the stylus made an impression or tiny dent in a paper tape which wound past a clockwork motor. The tape was then read by the operator.By 1843, the country was beginning to recover economically, and Morse again asked Congress for the $30,000 that would allow him to build a telegraph line from Washington to Baltimore, forty miles away. The House of Representatives eventually passed the bill containing the Morse appropriation, and the Senate approved it in the final hours of that Congress's last session. With President Tyler's signature, Morse received the cash he needed and began to carry out plans for an underground telegraph line.Realizing a Great InventionMorse had hired the ingenious construction engineer Ezra Cornell to lay the pipe carrying the wire, and although Cornell did his job superbly, one of Morse's partners, Congressman F. O. J. Smith, had purchased wire with defective insulation. Too much time had been wasted laying bad wire, and with the project on a rigid deadline, something had to be done quickly. Cornell suggested that the fastest and cheapest way of connecting Washington and Baltimore was to string wires overhead on trees and poles. The desperate Morse gave the go-ahead, and the line was completed in time for the dramatic and spectacularly successful link between the Supreme Court chamber of the Capitol building and the railroad station in Baltimore.Soon, as overhead wires connected cities up and down the Atlantic coast, the dots-and-dashes method that recorded messages on a long moving strip of paper was replaced by the operator's ability to interpret the code in real time (once the receiver was given two different types of "stop" pin that each made a different sound) and transcribe it into English letters as he heard it. Telegraph lines soon extended westward, and within Morse's own lifetime they connected the continents of Europe and America.Building the Transcontinental RailroadAlong with the development of the atomic bomb, the digging of the Panama Canal, and landing the first men on the moon, the construction of a transcontinental railroad was one of the United States' greatest technological achievements. Railroad track had to be laid over 2,000 miles of rugged terrain, including mountains of solid granite.Before the transcontinental railroad was completed, travel overland by stagecoach cost $1,000, took five or six months, and involved crossing rugged mountains and arid desert. The alternatives were to travel by sea around the tip of South America, a distance of 18,000 miles; or to cross the Isthmus of Panama, then travel north by ship to California. Each route took months and was dangerous and expensive. The transcontinental railroad would make it possible to complete the trip in five days at a cost of $150 for a first-class sleeper.The first spikes were driven in 1863, in the midst of the Civil War. Two companies competed to lay as much track as possible. The Central Pacific built east from Sacramento, Calif., while the Union Pacific built west from Omaha, Neb. The government gave the companies rights of way of 200 feet on each side of the track and financial aid of $16,000 to $48,000 for each mile of track laid.At first, the Union Pacific, which had flat terrain, raced ahead. The Central Pacific had to run train track through the Sierra Nevada Mountains. Working three shifts around the clock, Chinese immigrants hand drilled holes into which they packed black powder and later nitroglycerine. The progress in the tunnels through the mountains was agonizingly slow, an average of a foot a day.Stung by the Union Pacific's record of eight miles of track laid in a single day, the Central Pacific concocted a plan to lay 10 miles in a day. Eight Irish tracklayers put down 3,520 rails, while other workers laid 25,800 ties and drove 28,160 spikes in a single day. On May 10, 1869, at Promontory Summit, Utah, a golden spike was hammered into the final tie.The transcontinental railroad was built in six years almost entirely by hand. Workers drove spikes into mountains, filled the holes with black powder, and blasted through the rock inch by inch. Handcarts moved the drift from cuts to fills. Bridges, including one 700 feet long and 126 feet in the air, had to be constructed to ford streams. Thousands of workers, including Irish and German immigrants, former Union and Confederate soldiers, freed slaves, and especially Chinese immigrants played a part in the construction. Chinese laborers first went to work for the Central Pacific as it began crossing California's Sierra Nevada Mountains in 1865. At one point, 8,000 of the 10,000 men toiling for the Central Pacific were Chinese. At one point, Chinese workers were lowered in hand-woven reed baskets to drill blasting holes in the rock. They placed explosives in each hole, lit the fuses, and were, hopefully, pulled up before the powder was detonated. Explosions, freezing temperatures, and avalanches in the High Sierras killed hundreds. When Chinese workers struck for higher pay, a Central Pacific executive withheld their food supplies until they agreed to go back to work.Many of the railroad's builders viewed the Plains Indians as obstacles to be removed. General William Tecumseh Sherman wrote in 1867: "The more we can kill this year, the less will have to be killed the next year, for the more I see of these Indians the more convinced I am that they all have to be killed or be maintained as a species of paupers."Construction of the railroad provided many opportunities for financial chicanery, corruption, graft, and bribery. The greatest financial scandal of the 19th century grew out of the railroad's construction. The president of the Union Pacific helped found a construction company, called Credit Mobilier, which allowed investors, including several members of Congress, to grant lucrative construction contracts to themselves, while nearly bankrupting the railroad.The railroad had profound effects on American life. New phrases entered the American vocabulary such as "time's up," "time's a wasting," and "the train is leaving the station." It also led to the division of the nation into four standard time zones. In addition, the railroads founded many of the towns on the Great Plains on land grants they were awarded by the federal government, and then sold the land to settlers.The completion of the transcontinental railroad changed the nation. Western agricultural products, coal, and minerals could move freely to the east coast. Just as the Civil War united North and South, the transcontinental railroad united East and West. Passengers and freight could reach the west coast in a matter of days instead of months at one-tenth the cost. Settlers rushed into what was previously considered a desert wasteland. The 1890 Census would declare that the American frontier had disappeared. The railroad was a major cause.Equally important, the success of the transcontinental railroad encouraged an American faith that with money, determination, and organization anything can be accomplished. The construction of railroad demonstrated the effectiveness of complex military-like organization and assembly-line processes.Lowell SystemHoughton Mifflin Companion to US History:?The Lowell system was a method of factory management that evolved in the textile mills of Lowell, Massachusetts, owned by the Boston Manufacturing Company. In 1814, the Boston Company built America's first fully mechanized mill in Waltham, Massachusetts. Nine years later, the company built a complex of new mills at East Chelmsford, soon renamed Lowell in honor of the company's founder, Francis Lowell. With the production process fully mechanized, the principal limitation on the firm's output was the availability of labor, and here the company made its second innovation: it began to recruit young farm girls from the surrounding countryside. In order to attract these women and to?reassure?their families, the owners developed a paternalistic approach to management that became known as the Lowell system.The mill workers were housed in clean, well-run boardinghouses, were strictly supervised both at work and at home, and were paid unusually good wages. The farm girls responded with enthusiasm. They soon became renowned as excellent employees, and their lively self-improvement program (including a literary magazine) drew international attention. Few of the Lowell women worked more than a few years, but for every one who returned home to marry, two new ones appeared. By the 1830s, the Lowell system had become a national symbol of the fact that in America, humanity could go hand in hand with industrial success.Even at the?pinnacle?of its renown, however, conditions in Lowell had begun to deteriorate. In 1834, an economic?downturn?led to the mills' first wage cuts. In the 1840s, managers instituted a?speedup, requiring higher and higher output for the same hourly wage. The women formed the Lowell Female Labor Reform Association and tried to appeal to their employers and then to the state legislature through petitions. These led to state investigations in 1845 and 1846, but little changed. After 1848, conditions?deteriorated?further, as New England's textile industry began to suffer from overexpansion. Seeking cheaper labor, the mill owners turned increasingly to Irish immigrants and in the process discontinued the management policies they had devised to attract workers from the farms. By the 1850s, the Lowell system had been abandoned.0000 The History of the Telephone - Alexander Graham BellAlexander Graham Bell and Elisha Gray raced to invent the telephone.This model of Bell's first telephone is a duplicate of the instrument through which speech sounds were first transmitted electrically (1875).??Alexander Graham BellIn the 1870s, two inventorsElisha Gray?and Alexander Graham Bell both independently designed devices that could transmit speech electrically (the telephone). Both men rushed their respective designs to the patent office within hours of each other, Alexander Graham Bell?patented?his telephone first. Elisha Gray and Alexander Graham Bell entered into a famous legal battle over the invention of the telephone, which Bell won.Alexander Graham Bell - Evolution of the Telegraph into the TelephoneThe?telegraph?and telephone are both wire-based electrical systems, and Alexander Graham Bell's success with the telephone came as a direct result of his attempts to improve the telegraph.When Bell began experimenting with electrical signals, the telegraph had been an established means of communication for some 30 years. Although a highly successful system, the telegraph, with its dot-and-dash Morse code, was basically limited to receiving and sending one message at a time. Bell's extensive knowledge of the nature of sound and his understanding of music enabled him to conjecture the possibility of transmitting multiple messages over the same wire at the same time. Although the idea of a multiple telegraph had been in existence for some time, Bell offered his own musical or harmonic approach as a possible practical solution. His "harmonic telegraph" was based on the principle that several notes could be sent simultaneously along the same wire if the notes or signals differed in pitch.Alexander Graham Bell - Talk with ElectricityBy October 1874, Bell's research had progressed to the extent that he could inform his future father-in-law, Boston attorney Gardiner Greene Hubbard, about the possibility of a multiple telegraph. Hubbard, who resented the absolute control then exerted by the Western Union Telegraph Company, instantly saw the potential for breaking such a monopoly and gave Bell the financial backing he needed. Bell proceeded with his work on the multiple telegraph, but he did not tell Hubbard that he and Thomas Watson, a young electrician whose services he had enlisted, were also exploring an idea that had occurred to him that summer - that of developing a device that would transmit speech electrically.While Alexander Graham Bell and Thomas Watson worked on the harmonic telegraph at the insistent urging of Hubbard and other backers, Bell nonetheless met in March 1875 with?Joseph Henry, the respected director of the Smithsonian Institution, who listened to Bell's ideas for a telephone and offered encouraging words. Spurred on by Henry's positive opinion, Bell and Watson continued their work. By June 1875 the goal of creating a device that would transmit speech electrically was about to be realized. They had proven that different tones would vary the strength of an electric current in a wire. To achieve success they therefore needed only to build a working transmitter with a membrane capable of varying electronic currents and a receiver that would reproduce these variations in audible frequencies.First Sounds - TwangOn June 2, 1875, Alexander Graham Bell while experimenting with his technique called "harmonic telegraph" discovered he could hear sound over a wire. The sound was that of a twanging clock spring.Bell's greatest success was achieved on March 10, 1876, marked not only the birth of the telephone but the death of the multiple telegraph as well. The communications potential contained in his demonstration of being able to "talk with electricity" far outweighed anything that simply increasing the capability of a dot-and-dash system could imply.First Voice - Mr. Watson, come here. I want to see you.Alexander Graham Bell's notebook entry of 10 March 1876 describes his successful experiment with the telephone. Speaking through the instrument to his assistant, Thomas A. Watson, in the next room, Bell utters these famous first words, "Mr. Watson -- come here -- I want to see you."Spinning JennyJames Hargreaves?was a weaver living in the village of Stanhill in Lancashire. It is claimed that one day his daughter Jenny, accidentally knocked over over the family spinning wheel. The spindle continued to revolve and it gave Hargreaves the idea that a whole line of spindles could be worked off one wheel.In 1764 Hargreaves built what became known as the Spinning-Jenny. The machine used eight spindles onto which the thread was spun from a corresponding set of rovings. By turning a single wheel, the operator could now spin eight threads at once. Later, improvements were made that enabled the number to be increased to eighty. The thread that the machine produced was coarse and lacked strength, making it suitable only for the filling of weft, the threads woven across the warp.Hargreaves did not apply for a patent for his Spinning Jenny until 1770 and therefore others copied his ideas without paying him any money. It is estimated that by the time?James Hargreaves?died in 1778, over 20,000 Spinning-Jenny machines were being used in Britain.The Wright Brothers - First Flight, 1903Printer Friendly Version >>>On December 17, 1903, Orville Wright piloted the first powered airplane 20 feet above a wind-swept beach in North Carolina. The flight lasted 12 seconds and covered 120 feet. Three more flights were made that day with?Wilbur flies a glider in earlier testsKitty Hawk, Oct. 10, 1902.Orville's brother Wilbur piloting the record flight lasting 59 seconds over a distance of 852 feet.The brothers began their experimentation in flight in 1896 at their bicycle shop in Dayton, Ohio. They selected the beach at Kitty Hawk as their proving ground because of the constant wind that added lift to their craft. In 1902 they came to the beach with their glider and made more than 700 successful flights.Having perfected glided flight, the next step was to move to powered flight. No automobile manufacturer could supply an engine both light enough and powerful enough for their needs. So they designed and built their own. All of their hard work, experimentation and innovation came together that December day as they took to the sky and forever changed the course of history. The brothers notified several newspapers prior to their historic flight, but only one - the local journal - made mention of the event.Bessemer process0190500Bessemer process,?the first method discovered for mass-producing?steel. Though named after? HYPERLINK "" Sir Henry Bessemer?of England, the process evolved from the contributions of many investigators before it could be used on a broad commercial basis. It was apparently conceived independently and almost concurrently by Bessemer and by? HYPERLINK "" William Kelly?of the United States. As early as 1847, Kelly, a businessman-scientist of?Pittsburgh, Pa., began experiments aimed at developing a revolutionary means of removing impurities from pig iron by an air blast; Kelly theorized that not only would the air, injected into the molten iron, supply oxygen to react with the impurities, converting them into oxides separable as slag, but that the heat evolved in these reactions would increase the temperature of the mass, keeping it from solidifying during the operation. After several failures, he succeeded in proving his theory and rapidly producing steel ingots.In 1856 Bessemer, working independently in?Sheffield, developed and patented the same process. Whereas Kelly had been unable to perfect the process owing to a lack of financial resources, Bessemer was able to develop it into a commercial success. Another Englishman,? HYPERLINK "" Robert Forester Mushet, found that adding an alloy of carbon, manganese, and iron after the air-blowing was complete restored the carbon content of the steel while neutralizing the effect of remaining impurities, notably sulfur. A Swedish ironmaster,?Goran Goransson, redesigned the Bessemer furnace, or converter, making it reliable in performance. The end result was a means of mass-producing steel. The resultant volume of low-cost steel in Britain and the United States soon revolutionized building construction and provided steel to replace iron in railroad rails and many other uses.The?Bessemer converter?is a cylindrical steel pot approximately 6 m (20 feet) high, originally lined with a siliceous refractory. Air is blown in through openings (tuyeres) near the bottom, creating oxides of silicon and manganese, which become part of the slag, and of carbon, which are carried out in the stream of air. Within a few minutes an ingot of steel can be produced, ready for the forge or rolling mill.The original Bessemer converter was not effective in removing the phosphorus present in sizable amounts in most British and European iron ore. The invention in England, by?Sidney Gilchrist Thomas, of what is now called the? HYPERLINK "" Thomas-Gilchristconverter, which was lined with a basic material such as burned?limestone?rather than an (acid) siliceous material, overcame this problem. Another drawback to Bessemer steel, its retention of a small percentage of nitrogen from the air blow, was not corrected until the 1950s. The?open-hearth process, which was developed in the 1860s, did not suffer from this difficulty, and it eventually outstripped the Bessemer process to become the dominant steelmaking process until the mid-20th century. The open-hearth process was in turn replaced by the basic oxygen process, which is actually an extension and refinement of the Bessemer process.Assembly lineAn assembly line is a manufacturing process in which parts (usually interchangeable parts) are added to a product in a sequential manner using optimally planned logistics to create a finished product much faster than with handcrafting-type methods. The assembly line developed by Ford Motor Company between 1908 and 1915 made assembly lines famous in the following decade through the social ramifications of mass production, such as the affordability of the Ford Model T and the introduction of high wages for Ford workers. Henry Ford was the first to master the assembly line and was able to improve other aspects of industry by doing so (such as reducing labor hours required to produce a single vehicle, and increased production numbers and parts). However, the various preconditions for the development at Ford stretched far back into the 19th century, from the gradual realization of the dream of interchangeability, to the concept of reinventing workflow and job descriptions using analytical methods (the most famous example being scientific management). Ford was the first company to build large factories around the assembly line concept. Mass production via assembly lines is widely considered to be the catalyst which initiated the modern consumer culture by making possible low unit cost for manufactured goods. It is often said that Ford's production system was ingenious because it turned Ford's own workers into new customers. Put another way, Ford innovated its way to a lower price point and by doing so turned a huge potential market into a reality. Not only did this mean that Ford enjoyed much larger demand, but the resulting larger demand also allowed further economies of scale to be exploited, further depressing unit price, which tapped yet another portion of the demand curve. This bootstrapping quality of growth made Ford famous and set an example for other industries.Interchangeable PartsDuring the Industrial Revolution of the 19th century, machines took over most of the manufacturing work from men, and factories replaced craftsmen’s workshops. The event that laid the groundwork for this monumental change was the introduction of interchangeable parts, or pre-manufactured parts that were for all practical purposes identical, into the firearms industry. Interchangeable parts, popularized in America when Eli Whitney used them to assemble muskets in the first years of the 19th century, allowed relatively unskilled workers to produce large numbers of weapons quickly and at lower cost, and made repair and replacement of parts infinitely easier. PREINDUSTRIAL GUNMAKINGGunmaking was considered an extremely skilled craft in the 18th century, and firearms, including pistols and muskets, were all constructed by hand. In this way, every gun was a one-of-a-kind possession, and a gun broken could not be easily repaired. At the very least, the process was time consuming and expensive, as the gun had to be brought to a craftsman and repaired to order.In the mid-18th century, the French gunsmith Honoré LeBlanc suggested the gun parts be made from standardized patterns, so that all gun parts would follow the same design and could be easily replaced if broken. LeBlanc was not alone in imagining the potential value of this concept; an English naval engineer Samuel Bentham had earlier pioneered the use of uniform parts in the production of wooden pulleys for sailing ships. LeBlanc’s idea didn’t catch on in the French gun market, however, as competing gunsmiths saw clearly the effect that it would have on their craft. In 1789,?Thomas Jefferson, then serving as American minister to France, visited LeBlanc’s workshop and was impressed by his methods. Despite LeBlanc’s efforts, however, it would be left to another man to fully introduce interchangeable parts into the American—and later the international—weapons industry.ELI WHITNEY’S IMPRESSIVE DISPLAYIn 1797, when Congress voted to prepare the nation for war with France, including the appropriation of a large amount of funds for new weapons, the young inventor Eli Whitney–already known for his invention of the cotton gin in 1794–seized an opportunity to try to make his fortune. In mid-1798, he obtained a government contract to manufacture 10,000 muskets within an extraordinarily short time frame of less than two years.By January 1801, Whitney had failed to produce a single one of the promised weapons, and was called to?Washington?to justify his use of Treasury funds before a group that included outgoing president?John Adams?and Jefferson, now the president-elect. As the story goes, Whitney put on a display for the group, assembling muskets before their eyes by choosing (seemingly at random) from a supply of parts he brought with him. The performance earned Whitney widespread renown and renewed federal support. It was later proven, however, that Whitney’s demonstration was a fake, and that he had marked the parts beforehand and they were not exactly interchangeable. Still, Whitney received credit for what Jefferson claimed was the dawn of the machine age.THE IMPACT OF INTERCHANGEABLE PARTSWhitney proved to be an effective businessman and manager, dividing labor efficiently among his largely unskilled work force and building precision equipment that enabled the production of large numbers of identical parts quickly and at a relatively low cost. The last of the 10,000 muskets that Whitney had promised in his original contract came in eight years late, but were judged to be of superior quality, and he produced 15,000 more within the next four years.46a. The Age of the Automobile0381000Perhaps no invention affected American everyday life in the 20th century more than the automobile.Although the technology for theAUTOMOBILE?existed in the 19th century, it took?HENRY FORD?to make the useful gadget accessible to the American public. Ford used the idea of the?ASSEMBLY LINEfor automobile manufacturing. He paid his workers an unprecedented $5 a day when most laborers were bringing home two, hoping that it would increase their productivity. Furthermore, they might use their higher earnings to purchase a new car.Ford reduced options, even stating that the public could choose whatever color car they wanted — so long as it was black. The?MODEL T?sold for $490 in 1914, about one quarter the cost of the previous decade. By 1920, there were over 8 million registrations. The 1920s saw tremendous growth in automobile ownership, with the number of registered drivers almost tripling to 23 million by the end of the decade.Economic Spin-offsThe growth of the?AUTOMOBILE INDUSTRY?caused an economic revolution across the United States. Dozens of spin-off industries blossomed. Of course the demand for vulcanized rubber skyrocketed. Road construction created thousands of new jobs, as state and local governments began funding highway design.0254000Even the federal government became involved with the?FEDERAL HIGHWAY ACT OF 1921.?GAS STATIONS?began to dot the land, and mechanics began to earn a living fixing the inevitable problems. Oil and steel were two well-established industries that received a serious boost by the demand for automobiles. Travelers on the road needed shelter on long trips, so?MOTELS?began to line the major long-distance routes.Even cuisine was transformed by the automobile. The quintessential American foods — hamburgers, french fries, milk shakes, and apple pies — were hallmarks of the new roadside?DINER. Drivers wanted cheap, relatively fast food so they could be on their way in a hurry. Unfortunately, as new businesses flourished, old ones decayed. When America opted for the automobile, the nation's rails began to be neglected. As European nations were strengthening mass transit systems, individualistic Americans invested in the automobile infrastructure.Effects of the AutomobileThe social effects of the automobile were as great. Freedom of choice encouraged many family vacations to places previously impossible. Urban dwellers had the opportunity to rediscover pristine landscapes, just as rural dwellers were able to shop in towns and cities. Teenagers gained more and more independence with driving freedom. Dating couples found a portable place to be alone as the automobile helped to facilitate relaxed sexual attitudes.Americans experienced?TRAFFIC JAMS?for the first time, as well as traffic accidents and fatalities. Soon demands were made for licensure and safety regulation on the state level. Despite the drawbacks, Americans loved their cars. As more and more were purchased, drivers saw their worlds grow much larger.Inventing Edison's Lamp"Well, I'm not a scientist, I'm an inventor."(Thomas Edison, as quoted by his private secretary, A. O. Tate) …Of course, some scientists are also inventors. But there is a difference. A person acting scientifically is trying to understand the natural world, whether or not that understanding is economically useful. An inventor tries to create something new that will have practical application. In both cases there is a sense of challenge in the pursuit and a sense of achievement in the result.The InventorThomas Alva Edison was born 11 February 1847 in Milan, Ohio. He received little formal education, but showed an interest in chemistry and began experimenting to teach himself more about the subject. At age 12 he went to work selling newspapers and sundries on a train between Port Huron and Detroit. This gave him money to buy experimental materials, and also gave the voracious reader access to the Detroit Public Library.When Edison saved the life of a child in 1863, the grateful father (manager of the Mount Clemens railroad station) taught Edison telegraphy. Entranced by the new technology, Edison took up the life of an itinerant "Knight of the Key." But he continued to experiment with chemistry and began tinkering with electrical devices. He received his first patent (for an electric vote recorder) in 1868, but this invention failed to sell. During the next six years he developed a new stock ticker and a "quadruplex" telegraph, inventions that not only sold well but allowed him to establish an "invention factory" in 1876.The Light BulbWhen, in 1878, Edison announced that he had the answer and knew how to make an incandescent light, gas stocks around the world fell. The only problem was that his answer was wrong, and a year of hard work lay between Edison and success.The initial idea was to make a lamp with a platinum filament, a metal that was slow to oxidize and that had a high melting point. To keep the filament from overheating and burning out, Edison designed a complex regulating mechanism. The regulator would occasionally shunt current away from the filament, allowing it to cool off. Not only was this mechanism complicated to make and operate, but a light bulb that shut itself off every few minutes was hardly practical.Experiments with platinum proved useful, however. Edison discovered that hot filaments released gasses trapped in the metal. One of the hurdles to overcome was the creation of a better vacuum pump, one that could produce the very high vacuum needed. While experiments progressed through late 1878 and into 1879, Edison initiated work on other components needed for a practical lighting system, items like meters, cables, generators. He also began an economic survey of gas lighting, the technology he had to compete against.The light bulb effort was not the only project at Menlo Park; another was continuing work on improving Edison's telephone. The heart of Edison's transmitter (superior to Bell's by most accounts) consisted of a variable resistance carbon disk about the size of a button. Edison, like many of his competitors, had tried carbon as a lamp filament, but was discouraged by the material - it burned-out too quickly. Carbon had the highest melting point of any element, however. In the fall of 1879, experiments with carbon filaments resumed.Edison and his men recorded designs and experiments in notebooks all around the lab. Edison knew these books would be invaluable for backing patent claims, but probably thought little about their value to historians. In October 1879, Batchelor recorded a series of experiments with carbon filaments made from a variety of materials. Much mythology surrounds these experiments, but according to the notebooks a carbonized filament of uncoated cotton thread operated for a total of 14? hours on 22-23 October. While not the 40 hours of legend, this filament led the Menlo Park team to believe that they were on the right track.By 2 November that belief was such that Upton reported in a letter home, "The electric light is coming up. ... I have been offered $1,000 for five shares of my stock." Under pressure from his investors, Edison announced a public demonstration of the new lamp for New Year's Eve. Though not completely satisfied with the newest lamp (containing a carbonized paper filament), Edison nevertheless invited the public to Menlo Park. Visitors from New York City arrived on special trains to see the laboratory, the grounds, and Sarah Jordan's boarding house illuminated with about 100 of the new lamps, one of which is seen above. ................
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