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The telephone and electric light bulb are perhaps the two most influential nineteenth-century inventions.
Examine the advent of such late nineteenth century inventions as electricity, the telephone, and the lightbulb
Alexander Graham Bell invented the first workable telephone, basing his invention on a series of previous primitive examples.
Thomas Edison, commonly credited with inventing the light bulb, actually experimented with previous inventors' ideas to create the first commercially successful light bulb by perfecting the filament material.
Edison founded the successful Menlo Park research lab to produce innovation.
Edison and Nikola Tesla both advocated different systems of electricity delivery; eventually, Tesla's alternating current (AC) system proved more practical.
an electric current in which the direction of flow of the electrons reverses periodically having an average of zero, with positive and negative values (with a frequency of 50 Hz in Europe, 60 Hz in the US, 400 Hz for airport lighting, and some others); especially such a current produced by a rotating generator or alternator.
Nikola Tesla (Serbian Cyrillic: Н Т; 10 July 1856 – 7 January 1943) was a Serbian-American inventor, physicist, mechanical engineer, electrical engineer, and futurist. He was an important contributor to the use of commercial electricity, and is best known for his contributions to the modern alternating current (AC) electrical supply system.
Alexander Graham Bell is commonly credited as the inventor of the first practical telephone. He was the first to obtain a patent, in 1876, for an "apparatus for transmitting vocal or other sounds telegraphically," after experimenting with many primitive sound transmitters and receivers.
Bell's telephone transmitter (microphone) consisted of a double electromagnet, in front of which a membrane, stretched on a ring, carried an oblong piece of soft iron cemented to its middle. A funnel-shaped mouthpiece directed the voice sounds upon the membrane, and as it vibrated, the soft iron "armature" induced corresponding currents in the coils of the electromagnet. After traversing the wire, these currents passed through the receiver, which consisted of an electromagnet in a tubular metal can that had one end partially closed by a thin circular disc of soft iron. When the undulatory current passed through the coil of this electromagnet, the disc vibrated, thereby creating sound waves in the air.
The first long distance telephone call was made on August 10, 1876 by Bell from the family homestead in Brantford, Ontario, to his assistant located in Paris, Ontario, some 10 miles away. In June 1876, Bell exhibited a telephone prototype at the Centennial Exhibition in Philadelphia.
The telephone was instrumental to modernization and labour. It aided in the development of suburbs and the separation of homes and businesses, but also became the reason for the separation between women occupying the private sphere and men in the public sphere. This would continue to isolate women and the home.
Women were regarded as the most frequent users of the telephone. As a means of liberation, it enabled women to work in the telecommunications sector as receptionists and operators. The autonomy was celebrated as women were able to develop new relationships and nurture pre-existing ones in their private lives. Social relations are essential in the access and usage of telephone networks.
Thomas Edison's major innovation was the first industrial research lab, which was built in Menlo Park, New Jersey and was the first institution set up for the specific purpose of producing constant technological innovation. Most of the inventions produced there were legally attributed to Edison, though many employees carried out research and development under his direction.
Edison did not invent the first electric light bulb, but rather the first commercially practical incandescent light. Many earlier inventors had previously devised incandescent lamps, including Henry Woodward and Mathew Evans. Others who developed early and commercially impractical incandescent electric lamps included Humphry Davy, James Bowman Lindsay, Moses G. Farmer, William E. Sawyer, Joseph Swan, and Heinrich Göbel. These early bulbs had an extremely short life, were expensive to produce, or drew a high electric current, making them difficult to produce on a large commercial scale.
By 1879, Edison had produced a new concept: a high resistance lamp in a very high vacuum, which would burn for hundreds of hours. While earlier inventors had produced electric lighting in laboratory conditions, dating back to a demonstration of a glowing wire by Alessandro Volta in 1800, Edison concentrated on commercial application. He was able to sell the concept to homes and businesses by mass-producing relatively long-lasting light bulbs and creating a complete system for the generation and distribution of electricity.
Electric lighting in factories greatly improved working conditions, eliminating the heat and pollution caused by gas lighting, and reducing the fire hazard to the extent that cost of electricity for lighting was often offset by the reduction in fire insurance premiums. The light was much brighter than oil or gas lamps, and there was no soot. Although early electricity was very expensive compared to today, it was far cheaper and more convenient than oil or gas lighting.
In the years of 1831–1832, Michael Faraday discovered the operating principle of electromagnetic generators. The principle, later called Faraday's law, is that an electromotive force is generated in an electrical conductor that is subjected to a varying magnetic flux, as for example, a wire moving through a magnetic field.
The improvements in electrical generation technology increased the efficiency and reliability greatly in the 19th century. The first magnetos only converted a few percent of mechanical energy to electricity. By the end of the 19th century the highest efficiencies were over 90%.
In the early days of commercial electric power, transmission of electric power at the same voltage as used by lighting and mechanical loads restricted the distance between generating plant and consumers. In 1882, generation was with direct current (DC), which could not easily be increased in voltage for long-distance transmission. Different classes of loads (for example, lighting, fixed motors, and traction/railway systems) required different voltages, and so used different generators and circuits.
Due to this specialization of lines and because transmission was inefficient for low-voltage high-current circuits, generators needed to be near their loads. It seemed, at the time, that the industry would develop into what is now known as a distributed generation system with large numbers of small generators located near their loads.
The transmission of electric power with alternate current (AC) became possible after Lucien Gaulard and John Dixon Gibbs built what they called the secondary generator, an early transformer provided with 1:1 turn ratio and open magnetic circuit, in 1881.
The "War of Currents"
Edison's true success, like that of his friend Henry Ford, was in his ability to maximize profits by establishing mass-production systems and obtaining intellectual property rights. George Westinghouse became an adversary of Edison when he promoted the direct current (DC) for electric power distribution instead of the more easily transmitted alternating current (AC) system invented by Nikola Tesla and promoted by Westinghouse. Unlike DC, AC could be stepped up to very high voltages with transformers, sent over thinner and cheaper wires, and stepped down again at the destination for distribution to users.
The problem with DC was that power plants could only economically deliver DC electricity to customers within about one and a half miles (about 2.4 km) from the generating station, so that it was only suitable for central business districts. When George Westinghouse suggested using high-voltage AC instead, as it could carry electricity hundreds of miles with only marginal loss of power, Edison waged a "War of Currents" to prevent the adoption of the AC system.
The war against AC involved Edison in the development and promotion of the electric chair (using AC) as an attempt to portray AC to have greater lethal potential than DC. Edison continued to carry out a brief but intense campaign to ban the use of AC or to limit the allowable voltage for safety purposes. As part of this campaign, Edison's employees publicly electrocuted animals to demonstrate the dangers of AC. On one of the more notable occasions, Edison's workers electrocuted Topsy the elephant at Luna Park, near Coney Island, after she had killed several men and her owners wanted her put to death.
AC eventually replaced DC in most instances of generation and power distribution, enormously extending the range and improving the efficiency of power distribution. Though widespread use of DC ultimately lost favor for distribution, it exists today primarily in long-distance high-voltage direct current (HVDC) transmission systems.
Source: Boundless. “The Inventions of the Telephone and Electricity.” Boundless U.S. History. Boundless, 08 Aug. 2016. Retrieved 27 Sep. 2016 from https://www.boundless.com/u-s-history/textbooks/boundless-u-s-history-textbook/the-gilded-age-1870-1900-20/the-second-industrial-revolution-144/the-inventions-of-the-telephone-and-electricity-764-9474/