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Mairan, Jean Jacques d'Ortous de

1. Dates
Born: Béziers, 26 Nov. 1678
Died: Paris, 20 Feb. 1771
Dateinfo: Dates Certain
Lifespan: 93
2. Father
Occupation: Gentry
His family came from the minor nobility (which I am calling Gentry). His father, François d'Ortous died when Jean was four. His mother died in 1694, when he was not yet sixteen, leaving him to his own devices. Jean Jacques (and I assume his father) had the title of Lord (Sieur) of Mairan.
Mairan's own career seems clearly to indicate that he had inherited means. Though orphaned, he had no visible income other than inherited means until he became a member of the Académie in 1719, when he was over forty. Hence I conclude that he grew up in circumstances at least affluent.
3. Nationality
Birth: French
Career: French
Death: French
4. Education
Schooling: No University
1694-97, he studied in Toulouse.
1698-1702, he studied physics and mathematics in Paris, where Malebranche was one of his teachers.
There is no mention of university or degree.
5. Religion
Affiliation: Catholic (assumed)
6. Scientific Disciplines
Primary: Physics, Mechanics, Optics
Subordinate: Mathematics, Scientific Organization
He was concerned with a wide variety of subjects, including heat, light, sound, motion, the shape of the earth, and the aurora. His works include Dissertation sur les variations du barometre (Bordeaux, 1715), Dissertation sur la glace (Bordeaux, 1716), Dissertation sur la cause de la lumière des phosphores et des noctiluques (Bordeaux, 1717), and Dissertation sur l'estimation et la mesure des forces motrices des corps (1728). He also published a number of mathematical works.
Mairan replaced Fontenelle as perpetual secretary of the Académie. He was its assistant director in 1721, '27, '36, '44, '59, and director in '22, '28, '45, '60. He was also editor of the Journal des scavants.
7. Means of Support
Primary: Personal Means, Government, Patronage
1702, he returned home after his studies in Paris to Béziers, where he devoted himself to full-time study. He must have had some income from inherited property. His title was Lord (Sieur) of Mairan. He moved to Paris in 1718, but around 1723 he was back in Béziers for a few years.
He became a member of the Académie des Sciences in 1719. Later he received official lodging in the Louvre. He remained a pensionnaire until 1743, and served as secretary from 1741 to 43. In 1746 he was reinstated as pensionnaire géomètre.
It is reported that the Prince of Conti and other great lords heaped gifts upon him. He was also secretary to the Duke of Orleans.
8. Patronage
Types: Eccesiastic Official, Aristrocrat, Court Official, Government Official
At Béziers he ate every day with the Bishop of Béziers.
When he later organized a society in Béziers, it was founded under the protection of Cardinal de Fleury. The Cardinal, with M. de Maurepas, chose Mairan to replace Fontenelle.
Chancellor d'Aguesseau named him to edit the Journal des Scavants.
The King gave his society in Béziers a pension of 500 livres.
See his relations (above) with the Prince of Conti and the Duke of Orleans.
9. Technological Involvement
Type: Civil Engineering
After the Maritime Council commissioned the Académie, the Académie charged Mairan and Varignon in 1721 to investigate the gauging of ships in order, by means of an exact method, to prevent the complaints of commerce and the fraud of merchants. Mairan visited the ports of the Mediterranean in this capacity. In the end, the scheme of the Académie was not adopted.
10. Scientific Societies
Memberships: Académie Royal des Sciences, Royal Society, Institute Bologna, Russian Academy (St. Petersburg)
1718, associé of the Académie; 1719, pensionnaire géomètre until his death (with an interlude from 1743-46). See above for his offices in the Académie.
He also belonged to the Royal Societies of London, Edinburgh, and Uppsala, the Petersburg Academy, and the Institute of Bologna.
With Jean Bouillet and Antoine Portalon, he founded his own scientific society in Béziers about 1723.
  1. Grandjean de Fouchy's éloge in the Histoire de l'Academie royale des sciences, 1771, (Paris, 1774), pp. 89-104.
  2. Nouvelle biographie générale, 32, 936-40.
  3. Index biografique (Académie des sciences), p. 335.
Not Available and Not Consulted
  1. Abby R. Kleinbaum, Jean Jacques Dortous de Mairan (1678-1771), Columbia Univ. Ph.D. diss., 1970.
Compiled by:
Richard S. Westfall
Department of History and Philosophy of Science
Indiana University

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©1995 Al Van Helden
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