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Thomson, William
Thomson, William ( Lord Kelvin) (1824–1907) William Thomson became the foremost British physicist of his day, and made important contributions to Earth science. He took up the chair in natural philosophy at Glasgow in 1846 and occupied it for 53 years.
His interest in thermodynamics prompted his idea that the dissipation of heat from the Solar System could provide a clue to the age of the system, including that of the Earth. He was aware of the temperature gradient within deep mines and calculated a terrestrial heat loss. It was possible to calculate the time needed for this from the point when the crust of the Earth solidified. His figure of about 100 million years (Ma) was quite beyond anything previously suggested and caused prolonged controversy. It outraged the adherents of uniformitarianism, but it gave many of them pause for thought. At that time most geologists were content with less than 100 Ma for the age of the planet, and indeed for the Sun also. Kelvin summarized his ideas in this field in 1897, concluding that the Earth had been habitable for as little as 20 Ma, certainly not longer than 40 Ma. Clarence King in the United States estimated 24 Ma that same year. All this was to dismay Darwin, who needed a longer span of time for natural selection to bring about the living world of today. At the time of this debate scientists were ignorant of the generation of heat within the Earth by radioactive elements (radiogenic heat). When the contribution made by this hitherto unsuspected source of heat was later recognized, it became apparent that the Earth must be much older than 100 Ma. Thomson was knighted in 1866 and raised to the peerage as Lord Kelvin of Largs in 1892. He retired in 1899 and died in 1907. He is buried in Westminster Abbey. D. L. Dineley |
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PAUL HANCOCK and BRIAN J. SKINNER. "Thomson, William." The Oxford Companion to the Earth. 2000. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. PAUL HANCOCK and BRIAN J. SKINNER. "Thomson, William." The Oxford Companion to the Earth. 2000. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O112-ThomsonWilliam.html PAUL HANCOCK and BRIAN J. SKINNER. "Thomson, William." The Oxford Companion to the Earth. 2000. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O112-ThomsonWilliam.html |
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Thomson, William
Thomson, William, first Baron Kelvin (1824–1907), Scottish physicist, who had a profound influence as a synthesizer on 19th-century physics, and helped lay the foundations for this discipline today. He also made a great impact on maritime affairs when, in 1873, he undertook to write a series of articles on the magnetic compass for the magazine Good Words. After writing the first of them he realized that there were more problems concerning a compass than he had originally thought. For the next five years he experimented and improved its capability and reliability, partly by reducing the weight of the compass card itself and increasing the time of its swing, but mainly by working out and laying down rules for compensation by which the temporary and permanent magnetism of an iron or steel ship could be easily counteracted. Through his research, the compass binnacle was completely redesigned to house what became known as Kelvin spheres, balls of soft iron placed either side of the compass, which helped, with Flinders bars, to compensate for a ship's deviation. It was only after the completion of this work that he was in a position to write the second article of his series, five years after the publication of the first.
His other important contributions in the maritime field included his sounding apparatus, but he also invented a tide gauge, tidal harmonic analyser, and tide predictor, and worked on the advantages of the bulbous bow. |
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"Thomson, William." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "Thomson, William." The Oxford Companion to Ships and the Sea. 2006. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O225-ThomsonWilliam.html "Thomson, William." The Oxford Companion to Ships and the Sea. 2006. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O225-ThomsonWilliam.html |
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Thomson, William
Thomson, William ( Lord Kelvin) (1824–1907) A mathematician and physicist at Glasgow University, Kelvin is best known for his theory of thermodynamics, which he applied to his work on the age of the Earth. He used studies of the internal heat of the Earth, the age of the Sun, and tidal friction, to give an estimate of the Earth's age of about 20 million years. This led to conflict with geologists and evolutionists, who saw evidence that the Earth must be much older. See KELVIN SCALE.
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AILSA ALLABY and MICHAEL ALLABY. "Thomson, William." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. AILSA ALLABY and MICHAEL ALLABY. "Thomson, William." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O13-ThomsonWilliam.html AILSA ALLABY and MICHAEL ALLABY. "Thomson, William." A Dictionary of Earth Sciences. 1999. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-ThomsonWilliam.html |
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William Thomson
William Thomson see Kelvin, William Thomson, 1st Baron . |
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"William Thomson." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "William Thomson." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-X-ThmsnW.html "William Thomson." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-ThmsnW.html |
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Thomson, William
Thomson, William See Kelvin, Lord.
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Cite this article
"Thomson, William." A Dictionary of Astronomy. 1997. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "Thomson, William." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O80-ThomsonWilliam.html "Thomson, William." A Dictionary of Astronomy. 1997. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-ThomsonWilliam.html |
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