César-François Cassini de Thury
{{short description|French cartographer and astronomer (1714–1784)}}
{{about|the French-born cartographer and astronomer|his grandfather, the Italian-born astronomer for whom a Saturn probe was named|Giovanni Domenico Cassini}}
{{Infobox scientist
|name = César-François Cassini de Thury
|image =César-François Cassini - Jean-Marc Nattier.jpg
|image_size =250px
|caption = César-François Cassini de Thury,
miniature watercolour on ivory
by Jean-Marc Nattier
|birth_date = {{birth date|1714|6|17|df=yes}}
|birth_place =Thury-sous-Clermont, France
|death_date = {{death date and age|1784|9|4|1714|6|17|df=yes}}
|death_place = Paris, France
|children = Jean-Dominique Cassini
|residence =
|citizenship =
|nationality = French
|ethnicity =
|field = Cartography
Astronomy
|work_institutions = Paris Observatory
|alma_mater =
|doctoral_advisor =
|doctoral_students =
|known_for = Topographical map of France
|author_abbrev_bot =
|author_abbrev_zoo =
|influences =
|influenced =
|prizes =
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|signature =
}}
César-François Cassini de Thury (17 June 1714 – 4 September 1784), also called Cassini III or Cassini de Thury, was a French astronomer and cartographer.
Biography
Cassini de Thury was born in Thury-sous-Clermont, in the Oise department, the second son of Jacques Cassini and Suzanne Françoise Charpentier de Charmois.Jonathan Powell, From Cave Art to Hubble: A History of Astronomical Record Keeping, (Springer Nature Switzerland AG, 2019), 114 He was a grandson of Giovanni Domenico Cassini, and would become the father of Jean-Dominique Cassini, Comte de Cassini.Jonathan Powell, From Cave Art to Hubble: A History of Astronomical Record Keeping, (Springer Nature Switzerland AG, 2019), 115
In 1739, he became a member of the French Academy of Sciences as a supernumerary adjunct astronomer, in 1741 as an adjunct astronomer, and in 1745 as a full member astronomer.
In January 1751, he was elected a Fellow of the Royal Society.{{cite web| url= http://www2.royalsociety.org/DServe/dserve.exe?dsqIni=Dserve.ini&dsqApp=Archive&dsqCmd=Show.tcl&dsqDb=Persons&dsqPos=0&dsqSearch=%28Surname%3D%27cassini%27%29| title= Library and Archive Catalogue| publisher= Royal Society| accessdate= 21 December 2010}}{{dead link|date=January 2018 |bot=InternetArchiveBot |fix-attempted=yes }}
Cassini de Thury succeeded his father's official position in 1756 and continued the hereditary surveying operations.Jonathan Powell, From Cave Art to Hubble: A History of Astronomical Record Keeping, (Springer Nature Switzerland AG, 2019), 115 In 1744, he began the construction of a great topographical map of France,{{EB1911|inline=y|wstitle=Cassini|display=Cassini s.v. César François Cassini, or Cassini de Thury|volume=5|page=459|first=Agnes Mary|last=Clerke|author-link=Agnes Mary Clerke}} one of the landmarks in the history of cartography. Completed by his son Dominique, comte de Cassini and published by the Académie des Sciences from 1744 to 1793, its 180 plates are known as the Cassini map.
The post of director of the Paris Observatory was created for his benefit in 1771 when the establishment ceased to be a dependency of the French Academy of Sciences. A letter and proposal sent by Cassini de Thury to the Royal Society in London instigated the Anglo-French Survey (1784–1790), which measured the precise distance and direction between the Paris Observatory and the Royal Observatory, Greenwich, by way of a trigonometric survey.
His chief works are: La méridienne de l’Observatoire Royal de Paris (1744), an arc measurement correction of the Paris meridian (Dunkirk-Collioure arc measurement (Cassini de Thury and de Lacaille)); Description géométrique de la terre (1775); and Description géométrique de la France (1784), which was completed by his son ("{{nobr|Cassini IV}}").
César-François Cassini de Thury died of smallpox in Paris on 4 September 1784.
Works
- La méridienne de l’Observatoire Royal de Paris (1744)
- Description géométrique de la terre (1775)
- Description géométrique de la France (1784)
- {{Cite book|publisher=Imprimerie Royale|last=César-François Cassini de Thury|title= Relation d'un voyage en Allemagne |place= Paris|year= 1775|url= https://gutenberg.beic.it/webclient/DeliveryManager?pid=12196474}}
Bibliography
D. Aubin, Femmes, vulgarisation et pratique des sciences au siècle des Lumières : Les Dialogues sur l’astronomie et la Lettre sur la figure de la Terre de César-François Cassini de Thury, Brepols (2020)
See also
References
{{reflist}}
External links
- [http://gallica.bnf.fr/Search?idArk=&n=15&p=1&lang=FR&adva=1&adv=1&reset=&urlReferer=%2Fadvancedsearch%3Flang%3DFR&enreg=&tri=&submit1=Lancer+la+recherche&catsel1=f_title&cat1=&ope2=MUST&catsel2=f_creator&cat2=Cassini+de+Thury&ope3=MUST&catsel3=f_tdm&cat3=&date=daTo&daFr=&daTo=&biblio=Biblioth%C3%A8que+nationale+de+France&sel_source=toutSources&biblioSpecifique=Gallica&sel_provenance_Part=toutPartenaires&sel_provenance_Edist=toutSNE&dateMiseEnLigne=indexDateFrom&firstIndexationDateDebut=&firstIndexationDateFin=&tri= List of online works] available on Gallica
- [http://cassini.ehess.fr/fr/html/1_navigation.php Cassini map online on EHESS site]
- [https://web.archive.org/web/20170721154116/http://www.cartocassini.org/ cartocassini site], gathers old maps and allows for various manipulations, notably [https://web.archive.org/web/20170515024529/http://www.cartocassini.org/cartecassini/france.htm finding all Cassini maps in Gallica]
- [http://www.geoportail.gouv.fr/donnee/54/carte-de-cassini?c=1.0986386930841712,48.02768324127838&z=0.01841127537817229&l=GEOGRAPHICALGRIDSYSTEMS.CASSINI$GEOPORTAIL:OGC:WMTS%281%29&permalink=yes Cassini map in Géoportail (IGN)]
- [http://rumsey.geogarage.com/maps/cassinige.html Cassini map superimposed over Google Maps' map of France - David Rumsey]
- [https://bibnum.obspm.fr/ Paris Observatory digital library]
{{Authority control}}
{{DEFAULTSORT:Cassini De Thury, Cesar Francois}}
Category:Giovanni Domenico Cassini
Category:Scientists from Paris
Category:18th-century French astronomers
Category:18th-century French cartographers
Category:Members of the French Academy of Sciences
Category:Fellows of the Royal Society