History of electricity
Human fascination with electricity dates back thousands of years. In 600 BC Thales of Miletus, a Greek Philosopher discovered that electricity could generate from electron which we now call amber. Years later, the Roman author Pliny the Elder wrote about similar experiments in 70 AD in his Natural History. He also mentioned shocks given by torpedo fish one of the first few records of electrical charges in nature.
In 1600, the English Scientist William Gilbert published a report that proved that attraction by amber was not magnetic. He was the first person to use the term electric.
In 1672 the German physicist Otto Von Guericke reported the invention of an electric gadget and showed that electrified objects were able to transfer a part of their charge, or the ability to attract, to non-electrified objects. In about 1736, the French chemist Charles Francois Du Fay hypothesized that electricity consists of two kinds of fluid. Approximately ten years later, a German Clergyman, E Georg Von Kleist and a professor of the University of Leyden, Pieter van Musschenbroek, discovered (separately) that a glass vessel filled with water and charged by a friction source could reserve the charge for later use. This device because known as Leyden Jar and the prototype of the electric condenser.
Sir William Watson and Dr John Bevis of England improved the jar by coating the inside and the outside with tin foil, which could store enough charge to make sparks. Not until 1890s, however, when people understood electricity a little better, did they realize that both Du Fay and Watson were correct in their own individual ways. By then, the stage had been set to electrify human existence.
One parson who believed in Watson model of electricity as a single fluid was Benjamin Franklin of United States. Franklin lightning rod demonstrated that lightning was a form of electricity discharged from the clouds. In 1753 John Canton from England discovered electrostatic induction. Henry Cavendish, also English, compared the electric conductivities of equivalent solutions of electrolytes and also proved that the electric attraction is inversely proportional to the square of the distance between the charges.
However, the French Scientist, Charles Augustine de Coulomb was one of the first few scientists to measure electric charge. In 1780 an Italian anatomist Luigi Galvani executed experiments that observed the effects of static electricity on nerves and muscle of animals and became famous for his experiments on normal electricity, which led another Italian, Count Alessandro Volta to the discovery of electricity. In 1800, Volta announced that he had found a new source of electricity what is now known as the battery.
In 1807 Sir Humphrey Davy from England used current from a powerful battery based on Voltage to recover the electrolysis, pure sodium and potassium from molten soda and potash. In 1810, Davy demonstrated the Arc Lamp, the first electric lamp. In 1820 Hans Christian Forested of Denmark noticed that the electric current in a wire causes a compass needle to deflect.
Assisted by the voltaic cell and spurred on by Oersted discovery of electromagnetism in the 1820s scientists throughout Europe and America explored the nature of electricity and its relationship with other forces. The Englishman William Sturgeon invented the first electromagnet. Andre Marie Ampere, Professor of Mechanics in Paris, extended this investigation of the magnetic effect of electricity to include the interaction between two current carrying wires, which he showed to be the same as that between a wire and a magnet.
In France, Francois Arago discovered the magnetic effect of rotating copper disc. In England, Charles Babbage, famous as the pioneer of the digital computer, attempted to explain Arago effect in terms of Ampere抯 electrodynamics. In 1821, in Germany, Thomas Johann Seebeck discovered a connection between electricity and heat. In 1826 Georg Simon Ohm, a German, performed the experiment that led to the statement of his law, relating to current in a wire to voltage and resistance in the circuit. In New York, Hoseph Henry of Albany learned how to greatly increase the power of electromagnets and in 1831 devised the first electric bell. The Frenchman Simenon-Denis Poisson and Joseph-Louis Lagrange and the Englishman George Green also worked out many fundamental laws of electro-dynamics.
The long-term effect of the discoveries of this highly productive age may best be judged from some of the products that emerged from the discovery of electromagnetism ... motors, dynamos, transformers, telegraphs and telephones. In 1821, the Englishman Michael Faraday started a survey of experiments and theories of electro-magnetism and fascinated by the presumably circular nature of electromagnetic effects, madeaotator of an upright magnet in a cup of mercury, with a current carrying wire hanging down from above, with one end in mercury. When the circuit of wire and mercury and battery was completed, the wire began rotating around the magnet. This experiment, a decade later led to his momentous discovery THE PRODUCTION OF ELECTRICITY FROM MAGNETISM or electromagnetic induction. His idea of magnetic lines of force turned out tobe one of the most popular ideas in all of electrical science, though its true power was only realized by William Thomson (Lord Kelvin) and James Clarke Maxwell more than thirty years later.
Another scientist whose work was of significance was the British physicist James Prescott Joule who observed that the amount of heat produced by each form of energy is directly proportional to the amount of heat expended. Joule and Thomson worked together and in 1852 they observed that when a gas expands without performing work, its temperature falls. This was later applied to refrigeration technology.
19th Century was scattered with electrical inventions, an inevitable result of the research efforts of the first half of the century. While the pure scientists experimented in their laboratories, others were looking for practical applications for this wonderful new field with seemingly endless possibilities. Sir Humphry Davy invented his Arc Lamp. Faraday, his dynamo and transformer, Joseph Henry developed the electric bell, an electric motor in 1829, an early kind of telegraph in 1831 and the relay in 1835. Hyppolite Pixii in 1832 devised the first effective electric generator. Thomas Davenport of Virginia demonstrated practical application of motor in 1837. Prof. Charles Page of Washington built the first electric loco in 1839.
By the 1840s, generators were being used for electroplating which was one of the first practical uses of electricity. In 1850s the first efforts were made to apply generators to electric lighting using bright, glaring arc lights. In the 1860s more efficient generators like steam turbines were made, electricity became available on a large scale.
In 1876 Alexander Graham Bell invented the telephone and several other gadgets. Thomas Alva Edison demonstrated electric street lighting with incandescent lamp on the New Year抯 Eve 1879. Ten months earlier Joseph Swan of Great Britain had demonstrated his first successful electric lamp, a prototype of which he had developed in 1860. In the last quarter of the century there was a fabulous growth of electrical technology. Electric light was, of course, the most visible electrical invention. Between 1880 and 1910 the carbon filament lamp was the most important form of lighting. In 1898 Count Auer Von Welsbach of Germany introduced filaments of osmium and later of tantalum. Although tungsten was the ideal material, it was not used until 1908 when the American inventor William D. Coolidge compressed tungsten power into a rod. The evolution of lighting went on, and in 1910 neon lamp was developed and 1939 saw the first fluorescent light.
Of all the new technologies of the early 1900s one of the most exciting was ireless or radio technology. It drastically reduced distances between people with improved communications. Maxwell had predicated existence of eletromagnetic waves, but it took 25 years after his statements and equations were published for the waves to be produced and detected for the first time by Heinrich Hertz, a Professor of Physics at Karlsruhe University, Germany. Marchese Guglielmo Marconi, an Italian young man of 21 transmitted the first radio message in Morse code across the Atlantic in 1901 which used a oherer or detector for which he relied on the French Physicist and Physician Edouard Branly.
The one person who had contributed the maximum to oherer technology however, was a brilliant Indian Scientist Jagadis Chunder Bose, whose ideas were unfortunately not acknowledged. Bose demonstration of his mercury coherer technology had astounded member of the Royal Society, London in 1879. He had received his DSc from London University in the same year for this achievement. Marconi successfully suppressed this fact (A hundred years later Marconi invention was challenged at the Denver Convention of the Institution of Electrical and Electronics Engineers, USA June in 1997). Another contemporary scientist Karl Ferdinand Braun of Germany introduced the use of the crystal detector in receivers. His work of observing waveforms using a phosphor coated screen paved the way for cathode ray tubes, and eventually the television picture tube in 1926. John Logie Baird, a Scottish inventor developed a mechanical television system. His work became the basis of the British Broadcasting Corporation (BBC) first regular television broadcasts.