Jean Delambre
   HOME

TheInfoList



OR:

Jean Baptiste Joseph, chevalier Delambre (19 September 1749 – 19 August 1822) was a French mathematician,
astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...
,
historian of astronomy Astronomy is the oldest of the natural sciences, dating back to antiquity, with its origins in the religious, mythological, cosmological, calendrical, and astrological beliefs and practices of prehistory: vestiges of these are still found in ...
, and
geodesist Geodesy ( ) is the Earth science of accurately measuring and understanding Earth's figure (geometric shape and size), orientation in space, and gravity. The field also incorporates studies of how these properties change over time and equivale ...
. He was also director of the
Paris Observatory The Paris Observatory (french: Observatoire de Paris ), a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. Its histor ...
, and author of well-known books on the history of
astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
from ancient times to the 18th century.


Biography

After a childhood fever, he suffered from very sensitive eyes, and believed that he would soon go blind. For fear of losing his ability to read, he devoured any book available and trained his memory. He thus immersed himself in Greek and Latin literature, acquired the ability to recall entire pages verbatim weeks after reading them, became fluent in Italian, English and German and even wrote an unpublished ''Règle ou méthode facile pour apprendre la langue anglaise'' (Easy rule or method for learning English). Delambre's quickly achieved success in his career in astronomy, such that in 1788, he was elected a foreign member of the
Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences ( sv, Kungliga Vetenskapsakademien) is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special ...
. In 1790, to establish a universally accepted foundation for the definition of measures, the National Constituent Assembly asked the
French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific me ...
to introduce a new unit of measurement. The academics decided on the metre, defined as 1 / 10,000,000 of the distance from the North Pole to the equator, and prepared to organise an expedition to measure the length of the
meridian arc In geodesy and navigation, a meridian arc is the curve between two points on the Earth's surface having the same longitude. The term may refer either to a segment of the meridian, or to its length. The purpose of measuring meridian arcs is to de ...
between
Dunkirk Dunkirk (french: Dunkerque ; vls, label=French Flemish, Duunkerke; nl, Duinkerke(n) ; , ;) is a commune in the department of Nord in northern France.Barcelona Barcelona ( , , ) is a city on the coast of northeastern Spain. It is the capital and largest city of the autonomous community of Catalonia, as well as the second most populous municipality of Spain. With a population of 1.6 million within ci ...
. This portion of the
meridian Meridian or a meridian line (from Latin ''meridies'' via Old French ''meridiane'', meaning “midday”) may refer to Science * Meridian (astronomy), imaginary circle in a plane perpendicular to the planes of the celestial equator and horizon * ...
, which also passes through Paris, was to serve as the basis for the length of the quarter meridian, connecting the
North Pole The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. It is called the True North Pole to distinguish from the Mag ...
with the
Equator The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can als ...
. In April 1791, the academy's Metric Commission confided this mission to Jean-Dominique de Cassini,
Adrien-Marie Legendre Adrien-Marie Legendre (; ; 18 September 1752 – 9 January 1833) was a French mathematician who made numerous contributions to mathematics. Well-known and important concepts such as the Legendre polynomials and Legendre transformation are named ...
and
Pierre Méchain Pierre François André Méchain (; 16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep-sky objects and comets. Life Pierre Méchain was born i ...
. Cassini was chosen to head the northern expedition but, as a royalist, he refused to serve under the revolutionary government after the arrest of
King Louis XVI Louis XVI (''Louis-Auguste''; ; 23 August 175421 January 1793) was the last King of France before the fall of the monarchy during the French Revolution. He was referred to as ''Citizen Louis Capet'' during the four months just before he was e ...
on his
Flight to Varennes The royal Flight to Varennes (french: Fuite à Varennes) during the night of 20–21 June 1791 was a significant event in the French Revolution in which King Louis XVI of France, Queen Marie Antoinette, and their immediate family unsuccessfull ...
. On 15 February 1792, Delambre was elected unanimously a member of the
French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific me ...
and in May 1792, after Cassini's final refusal, was placed in charge of the northern expedition, measuring the meridian from Dunkirk to
Rodez Rodez ( or ; oc, Rodés, ) is a small city and commune in the South of France, about 150 km northeast of Toulouse. It is the prefecture of the department of Aveyron, region of Occitania (formerly Midi-Pyrénées). Rodez is the seat of the ...
in the south of France.
Pierre Méchain Pierre François André Méchain (; 16 August 1744 – 20 September 1804) was a French astronomer and surveyor who, with Charles Messier, was a major contributor to the early study of deep-sky objects and comets. Life Pierre Méchain was born i ...
headed the southern expedition, measuring from Barcelona to Rodez. The measurements were finished in 1798. The gathered data were presented to an international conference of savants in Paris the following year. In 1801,
First Consul The Consulate (french: Le Consulat) was the top-level Government of France from the fall of the Directory in the coup of 18 Brumaire on 10 November 1799 until the start of the Napoleonic Empire on 18 May 1804. By extension, the term ''The Con ...
Napoléon Bonaparte Napoleon Bonaparte ; it, Napoleone Bonaparte, ; co, Napulione Buonaparte. (born Napoleone Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French military commander and political leader who ...
took the presidency of the
French Academy of Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV of France, Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French Scientific me ...
and appointed Delambre its Permanent Secretary for the Mathematical Sciences, a post he held until his death. In 1803, he was elected a member of the
American Philosophical Society The American Philosophical Society (APS), founded in 1743 in Philadelphia, is a scholarly organization that promotes knowledge in the sciences and humanities through research, professional meetings, publications, library resources, and communit ...
in
Philadelphia Philadelphia, often called Philly, is the largest city in the Commonwealth of Pennsylvania, the sixth-largest city in the U.S., the second-largest city in both the Northeast megalopolis and Mid-Atlantic regions after New York City. Sinc ...
. After Méchain's death in 1804, he was appointed director of the
Paris Observatory The Paris Observatory (french: Observatoire de Paris ), a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. Its histor ...
. He was also professor of Astronomy at the
Collège de France The Collège de France (), formerly known as the ''Collège Royal'' or as the ''Collège impérial'' founded in 1530 by François I, is a higher education and research establishment (''grand établissement'') in France. It is located in Paris ne ...
. The same year he married Elisabeth-Aglaée Leblanc de Pommard, a widow with whom he had lived already for a long time. Her son, Achille-César-Charles de Pommard (1781–1807) assisted Delambre on several occasions in his astronomical and geodetical surveys, notably the measuring of the baselines for the meridian survey, and the latitude definition for Paris in December 1799 which was presented to the Conference of Savants. Delambre was one of the first astronomers to derive astronomical equations from analytical formulas, was the author of Delambre's Analogies and, after the age of 70, also the author of works on the
history of astronomy Astronomy is the oldest of the natural sciences, dating back to antiquity, with its origins in the religious, mythological, cosmological, calendrical, and astrological beliefs and practices of prehistory: vestiges of these are still found in ...
like the ''Histoire de l'astronomie''. He was a knight (''chevalier'') of the
Order of Saint Michael , status = Abolished by decree of Louis XVI on 20 June 1790Reestablished by Louis XVIII on 16 November 1816Abolished in 1830 after the July RevolutionRecognised as a dynastic order of chivalry by the ICOC , founder = Louis XI of France , hig ...
and of the
Légion d'honneur The National Order of the Legion of Honour (french: Ordre national de la Légion d'honneur), formerly the Royal Order of the Legion of Honour ('), is the highest French order of merit, both military and civil. Established in 1802 by Napoleon ...
. His name is also one of the 72 names inscribed on the Eiffel tower. He was elected a Foreign Honorary Member of the
American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and ...
in 1822. Delambre died in 1822 and was interred in
Père Lachaise Cemetery Père Lachaise Cemetery (french: Cimetière du Père-Lachaise ; formerly , "East Cemetery") is the largest cemetery in Paris, France (). With more than 3.5 million visitors annually, it is the most visited necropolis in the world. Notable figures ...
in Paris. The crater
Delambre Jean Baptiste Joseph, chevalier Delambre (19 September 1749 – 19 August 1822) was a French mathematician, astronomer, historian of astronomy, and geodesist. He was also director of the Paris Observatory, and author of well-known books on th ...
on the Moon is named after him. Delambre was an atheist.George William Foote, ed. (1887). Progress: a monthly magazine of advanced thought, Volume 7. Progressive Publishing Co. p. 127. DELAMBRE (Jean Baptiste Joseph), French astronomer, born at Amiens, 19 September 1749, studied under Lalande and became, like his master, an Atheist.


Works


Méthodes analytiques pour la détermination d'un arc du méridien
(Crapelet, Paris, 1799) *''Notice historique sur M. Méchain, lue le 5 messidor XIII'' (Baudouin, Paris, January 1806; this is the eulogy on the late Pierre Méchain, read at the Academy by Secretary Delambre on 24 June 1805)
Base du système métrique décimal, ou Mesure de l'arc du méridien – compris entre les parallèles de Dunkerque et Barcelone, exécutée en 1792 et années suivantes, par MM. Méchain et Delambre.
(editor; Baudouin, Imprimeur de l'Institut National; Paris; 3. vol.; January 1806, 1807, 1810; this includes both his own and Méchain's data gathered during the meridian survey 1792–1799 and calculations derived thereof) *''Rapport historique sur le progrès des sciences mathématiques depuis 1799'' (Imprimerie Impériale, Paris, 1810) *
Tables écliptiques des satellites de Jupiter: d'après la théorie de M. le Marquis de Laplace, et la totalité des observations faites depuis 1662 jusqu'à l'an 1802
' (Paris : Courcier, 1817.) *A history of astronomy, comprising four works and six volumes in all: **''Histoire de l'astronomie ancienne'', Paris: Mme Ve Courcier, 1817. 2 volumes; vol. 1, lxxii, 556 pp., 1 folded plate; vol. 2, viii, 639 pp., 16 folded plates. .
Reprinted by New York and London: Johnson Reprint Corporation, 1965 (''Sources of Science'', #23), with a new preface by Otto Neugebauer. .
Text on line: vol. 1

vol. 2

**''Histoire de l'astronomie du moyen age'', Paris: Mme Ve Courcier, 1819. lxxxiv, 640 pp., 17 folded plates. .
Reprinted by New York and London: Johnson Reprint Corporation, 1965 (''Sources of Science'', #24.) .
Also reprinted by Paris: J. Gabay, 2006. .
Text on line

**''Histoire de l'astronomie moderne'', Paris: Mme Ve Courcier, 1821. 2 volumes; vol. 1, lxxxii, 715 pp., 9 folded plates; vol. 2, 804 pp., 8 folded plates. .
Reprinted by New York and London: Johnson Reprint Corporation, 1969 (''Sources of Science'', #25), with a new introduction and tables of contents by I. Bernard Cohen. .
Also reprinted by Paris: Editions Jacques Gabay, 2006. .
This takes the history to the 17th century.
Text on line: both volumes, with usable plates

vol. 1

vol. 2

**''Histoire de l'astronomie au dix-huitième siècle'', edited by Claude-Louis Mathieu, Paris: Bachelier (successeur de Mme Ve Courcier), 1827. lii, 796 p., 3 folded plates.
Reprinted by Paris: J. Gabay, 2004. .
This includes the history of astronomy in the 18th century, especially critiques of his colleagues at the Academy, which he withheld to be published posthumously.
Text on line

with usable plates

* iarchive:grandeuretfigure00dela, Grandeur et figure de la terre, ouvrage augmenté de notes, de cartes (1912)(edited by Guillaume Bigourdan, Gauthiers-Villars, Paris, 1912; about the
figure of the Earth Figure of the Earth is a Jargon, term of art in geodesy that refers to the size and shape used to model Earth. The size and shape it refers to depend on context, including the precision needed for the model. A Spherical Earth, sphere is a well-k ...

Some works are digitalized
on
Paris Observatory The Paris Observatory (french: Observatoire de Paris ), a research institution of the Paris Sciences et Lettres University, is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world. Its histor ...
digital library. File:Delambre-1.jpg, 1817 copy of "''Tables écliptiques des satellites de Jupiter''" File:Delambre-4.jpg, 1817 introduction to "''Tables écliptiques des satellites de Jupiter''" File:Delambre-5.jpg, 1817 introduction to "''Tables écliptiques des satellites de Jupiter''" File:Delambre-6.jpg, 1817 introduction to "''Tables écliptiques des satellites de Jupiter''" File:Delambre-7.jpg, Excerpt from an 1817 copy of "''Tables écliptiques des satellites de Jupiter''"


See also

* Delambre analogies *
History of the metre The history of the metre starts with the Scientific Revolution that is considered to have begun with Nicolaus Copernicus's publication of '' De revolutionibus orbium coelestium'' in 1543. Increasingly accurate measurements were required, and ...
* Meridian arc of Delambre and Méchain *
Seconds pendulum A seconds pendulum is a pendulum whose period is precisely two seconds; one second for a swing in one direction and one second for the return swing, a frequency of 0.5 Hz. Pendulum A pendulum is a weight suspended from a pivot so that ...


References


Further reading

* Ken Alder: ''The Measure of All Things – The Seven-Year Odyssey and Hidden Error That Transformed the World'' (The Free Press; New York, London, Toronto, Sydney, Singapore; 2002; )


External links

* *
A brief biography of Delambre
partly from the 1880 Encyclopædia Britannica, including an account of Delambre's intervention to request liberation (from French imprisonment) of James Smithson, who went on to endow the foundation of the Smithsonian Institution, national museum of the United States of America
Portrait of Jean Baptiste Joseph Delambre from the Lick Observatory Records Digital Archive, UC Santa Cruz Library's Digital CollectionsJean Baptiste Joseph Delambre papers Jean Baptiste Joseph Delambre papers, MSS 458
a
L. Tom Perry Special Collections
Brigham Young University Brigham Young University (BYU, sometimes referred to colloquially as The Y) is a private research university in Provo, Utah. It was founded in 1875 by religious leader Brigham Young and is sponsored by the Church of Jesus Christ of Latter-day ...
{{DEFAULTSORT:Delambre, Jean Baptiste Joseph 1749 births 1822 deaths People from Amiens 19th-century French astronomers Burials at Père Lachaise Cemetery Chevaliers of the Légion d'honneur Collège de France faculty Fellows of the American Academy of Arts and Sciences Fellows of the Royal Society French atheists 18th-century French astronomers 19th-century French historians Historians of astronomy Members of the Royal Swedish Academy of Sciences Officers of the French Academy of Sciences 18th-century French mathematicians 19th-century French mathematicians French male writers 19th-century male writers French geodesists