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1 Briggs, Henry
SUBJECT AREA: Electronics and information technology[br]b. February 1561 Warley Wood, Yorkshire, Englandd. 26 January 1630 Oxford, England[br]English mathematician who invented common, or Briggsian, logarithms and whose writings led to their general acceptance throughout Europe.[br]After education at Warley Grammar School, Briggs entered St John's College, Cambridge, in 1577 and became a fellow in 1588. Having been Reader of the Linacre Lecture in 1592, he was appointed to the new Chair in Geometry at Gresham House (subsequently Gresham College), London, in 1596. Shortly after, he concluded that the logarithms developed by John Napier would be much more useful if they were calculated to the decimal base 10, rather than to the base e (the "natural" number 2.71828…), a suggestion with which Napier concurred. Until the advent of modern computing these decimal logarithms were invaluable for the accurate calculations involved in surveying, navigation and astronomy. In 1619 he accepted the Savilian Chair in Geometry at Oxford University, having two years previously published the base 10 logarithms of 1,000 numbers. The year 1624 saw the completion of his monumental Arithmetica Logarithmica, which contained fourteen-figure logarithms of 30,000 numbers, together with their trigonometric sines to fifteen decimal places and their tangents and secants to ten places![br]Bibliography1617, Logarithmorum Chilias Primi (the first published reference to base 10 logarithms). 1622, A Treatise of the North West Passage to the South Sea: Through the Continent ofVirginia and by Fretum Hudson.1633, Arithmetica Logarithmica, Gouda, the Netherlands; pub. in 1633 as Trigonmetria Britannica, London.Further ReadingE.T.Bell, 1937, Men of Mathematics, London: Victor Gollancz. See also Burgi, Jost.KF -
2 Electronics and information technology
See also: INDEX BY SUBJECT AREA[br]Byron, Ada AugustaNapier, JohnRiche, Gaspard-Clair-François-MarieSchickhard, WilhelmBiographical history of technology > Electronics and information technology
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3 Burgi, Jost
SUBJECT AREA: Horology[br]b. 28 February 1552 Lichtensteig, Switzerlandd. 31 January 1632 Kassel, Germany[br]Swiss clockmaker and mathematician who invented the remontoire and the cross-beat escapement, also responsible for the use of exponential notation and the calculation of tables of anti-logarithms.[br]Burgi entered the service of Duke William IV of Hesse in 1579 as Court Clockmaker, although he also assisted William with his astronomical observations. In 1584 he invented the cross-beat escapement which increased the accuracy of spring-driven clocks by two orders of magnitude. During the last years of the century he also worked on the development of geometrical and astronomical instruments for the Royal Observatory at Kassel.On the death of Duke Wilhelm in 1603, and with news of his skills having reached the Holy Roman Emperor Rudolph II, in 1604 he went to Prague to become Imperial Watchmaker and to assist in the creation of a centre of scientific activity, subsequently becoming Assistant to the German astronomer, Johannes Kepler. No doubt this association led to an interest in mathematics and he made significant contributions to the concept of decimal fractions and the use of exponential notation, i.e. the use of a raised number to indicate powers of another number. It is likely that he was developing the idea of logarithms at the same time (or possibly even before) Napier, for in 1620 he made his greatest contribution to mathematics, science and, eventually, engineering, namely the publication of tables of anti-logarithms.At Prague he continued the series of accurate clocks and instruments for astronomical measurements that he had begun to produce at Kassel. At that period clocks were very poor timekeepers since the controller, the foliot or balance, had no natural period of oscillation and was consequently dependent on the driving force. Although the force of the driving weight was constant, irregularities occurred during the transmission of the power through the train as a result of the poor shape and quality of the gearing. Burgi attempted to overcome this directly by superb craftsmanship and indirectly by using a remontoire. This device was wound at regular intervals by the main driving force and fed the power directly to the escape wheel, which impulsed the foliot. He also introduced the crossbeat escapement (a variation on the verge), which consisted of two coupled foliots that swung in opposition to each other. According to contemporary evidence his clocks produced a remarkable improvement in timekeeping, being accurate to within a minute a day. This improvement was probably a result of the use of a remontoire and the high quality of the workmanship rather than a result of the cross-beat escapement, which did not have a natural period of oscillation.Burgi or Prague clocks, as they were known, were produced by very few other makers and were supplanted shortly afterwards by the intro-duction of the pendulum clock. Burgi also produced superb clockwork-driven celestial globes.[br]Principal Honours and DistinctionsEnnobled 1611.BibliographyBurgi only published one book, and that was concerned with mathematics.Further ReadingL.von Mackensen, 1979, Die erste Sternwarte Europas mit ihren Instrumenten and Uhren—400 Jahre Jost Burgi in Kassel, Munich.K.Maurice and O.Mayr (eds), 1980, The Clockwork Universe, Washington, DC, pp. 87– 102.H.A.Lloyd, 1958, Some Outstanding Clocks Over 700 Years, 1250–1950, London. E.T.Bell, 1937, Men of Mathematics, London: Victor Gollancz.See also: Briggs, HenryKF / DV -
4 Riche, Gaspard-Clair-François-Marie, Baron de Prony
SUBJECT AREA: Electronics and information technology[br]b. c. 1755 France d. c. 1839[br]French mathematician who used the method of differences to calculate logarithms and trigonometric functions,[br]Whilst Directeur of the Bureau du Cadastre, Prony was made responsible for a project to determine the trigonometric functions of the centesimal units of 90°, i.e. the right angle was successively divided into 100 grades containing 100 minutes, which in turn each consisted of 100 seconds. This work produced tables (known as the Table de Cadastre) of the natural sines to twenty-two decimal places and the logarithms of sines and tangents to fourteen places. Although the tables as calculated were never published, tables based on them (presumably derived for the more familiar degree, minute and second sub-divisions of a right-angle by interpolation) have since appeared.KFBiographical history of technology > Riche, Gaspard-Clair-François-Marie, Baron de Prony
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5 Napier (Neper), John
SUBJECT AREA: Electronics and information technology[br]b. 1550 Merchiston Castle, Edinburgh, Scotlandd. 4 April 1617 Merchiston Castle, Edinburgh, Scotland[br]Scottish mathematician and theological writer noted for his discovery of logarithms, a powerful aid to mathematical calculations.[br]Born into a family of Scottish landowners, at the early age of 13 years Napier went to the University of St Andrews in Fife, but he apparently left before taking his degree. An extreme Protestant, he was active in the struggles with the Roman Catholic Church and in 1594 he dedicated to James VI of Scotland his Plaine Discovery of the Whole Revelation of St John, an attempt to promote the Protestant case in the guise of a learned study. About this time, as well as being involved in the development of military equipment, he devoted much of his time to finding methods of simplifying the tedious calculations involved in astronomy. Eventually he realized that by representing numbers in terms of the power to which a "base" number needed to be raised to produce them, it was possible to perform multiplication and division and to find roots, by the simpler processes of addition, substraction and integer division, respectively.A description of the principle of his "logarithms" (from the Gk. logos, reckoning, and arithmos, number), how he arrived at the idea and how they could be used was published in 1614 under the title Mirifici Logarithmorum Canonis Descriptio. Two years after his death his Mirifici Logarithmorum Canonis Constructio appeared, in which he explained how to calculate the logarithms of numbers and gave tables of them to eight significant figures, a novel feature being the use of the decimal point to distinguish the integral and fractional parts of the logarithm. As originally conceived, Napier's tables of logarithms were calculated using the natural number e(=2.71828…) as the base, not directly, but in effect according to the formula: Naperian logx= 107(log e 107-log e x) so that the original Naperian logarithm of a number decreased as the number increased. However, prior to his death he had readily acceded to a suggestion by Henry Briggs that it would greatly facilitate their use if logarithms were simply defined as the value to which the decimal base 10 needed to be raised to realize the number in question. He was almost certainly also aware of the work of Joost Burgi.No doubt as an extension of his ideas of logarithms, Napier also devised a means of manually performing multiplication and division by means of a system of rods known as Napier's Bones, a forerunner of the modern slide-rule, which evolved as a result of successive developments by Edmund Gunther, William Oughtred and others. Other contributions to mathematics by Napier include important simplifying discoveries in spherical trigonometry. However, his discovery of logarithms was undoubtedly his greatest achievement.[br]BibliographyNapier's "Descriptio" and his "Constructio" were published in English translation as Description of the Marvelous Canon of Logarithms (1857) and W.R.MacDonald's Construction of the Marvelous Canon of Logarithms (1889), which also catalogues all his works. His Rabdologiae, seu Numerationis per Virgulas Libri Duo (1617) was published in English as Divining Rods, or Two Books of Numbering by Means of Rods (1667).Further ReadingD.Stewart and W.Minto, 1787, An Account of the Life Writings and Inventions of John Napier of Merchiston (an early account of Napier's work).C.G.Knott (ed.), 1915, Napier Tercentenary Memorial Volume (the fullest account of Napier's work).KF
См. также в других словарях:
Briggs,Henry — Briggs (brĭgz), Henry. 1561 1630. English mathematician who devised the decimal based system of logarithms and invented the modern method of long division. * * * … Universalium
Briggs, Henry — ▪ English mathematician born February 1561, Warleywood, Yorkshire, England died January 26, 1630, Oxford English mathematician who invented the common, or Briggsian, logarithm. His writings were mainly responsible for the widespread… … Universalium
Briggs , Henry — (1561–1630) English mathematician Born in Warley Wood, Briggs became a fellow of Cambridge University in 1588 and was later made a lecturer (1592) and a professor (1596) of geometry at Gresham College, London. He is remembered chiefly for the… … Scientists
Briggs, Henry — ► (1561 1630) Matemático inglés. Introdujo, en colaboración con Napier, los logaritmos decimales … Enciclopedia Universal
BRIGGS, HENRY — a distinguished English mathematician; first Savilian professor at Oxford; made an important improvement on the system of logarithms, which was accepted by Napier, the inventor, and is the system now in use (1561 1631) … The Nuttall Encyclopaedia
Briggs — Briggs, Henry … Enciclopedia Universal
BRIGGS (H.) — BRIGGS HENRY (1561 1630) Mathématicien anglais dont le nom est attaché à la découverte des logarithmes décimaux (appelés aussi logarithmes vulgaires ou briggsiens). Le caractère instrumental de ce nouvel outil mathématique lui valut une large et… … Encyclopédie Universelle
Henry Briggs — Pour les articles homonymes, voir Briggs. Henry Briggs Naissance Février 1556 Warley Wood (Angleterre) Décès 26 janvier 1630 Oxford (Angleterre) … Wikipédia en Français
Henry Briggs — Henry Briggs, Familienname auch Brigde oder Brigs, (* Februar 1561[1] in Warleywood bei Halifax (West Yorkshire); † 26. Januar 1630 in Oxford) war ein englischer Mathematiker. Inhaltsverzeichnis 1 Leben 2 Schriften … Deutsch Wikipedia
Henry Briggs — Nacimiento Febrero de 1561 Warley wood, Yorkshire, Inglaterra Fallecimiento 26 de Enero de 1630, a la edad de 68 años Oxford, Inglaterra Residencia Inglaterra … Wikipedia Español
Briggs — could refer to: Briggs cliff, a fictional place in Fullmetal Alchemist manga Briggs (crater), a lunar crater Briggs Initiative, either of two pieces of Californian legislation sponsored by John Briggs Briggs Islet, Tasmania, Australia Briggs,… … Wikipedia