Person: Barbier, Joseph Émile
JosephÉmile Barbier was a French astronomer and mathematician.
Mathematical Profile (Excerpt):
 Barbier began his studies at the École Normale Supérieure in 1857 and there he impressed everyone with his deep understanding of mathematics.
 Having received his licentiate Barbier proceeded toward his "agregation".
 An appointment in Nice might have been attractive but Barbier's keen mind and the subtlety which he saw in even elementary mathematics did not make him a good teacher since the pupils in the Lycée in Nice failed to gain anything from Barbier.
 He was offered a post at the Paris Observatory by Le Verrier and Barbier left Nice to begin work as an assistant astronomer.
 As time went by, however, Barbier's behaviour became more and more peculiar.
 Bertrand discovered that although Barbier was clearly unstable mentally, he was still able to make superb original contributions to mathematics.
 He encouraged Barbier to return to scientific writing and, although he never recovered his sanity, he wrote many excellent and original mathematical papers.
 Bertrand, as Secretary to the Académie des Sciences, was able to find a small source of income for Barbier from a foundation which was associated with the Académie.
 Barbier, although mentally unstable, was a gentle person and it was seen that, with his small income, it was possible for him to live in the community.
 This was arranged and Barbier spent his last few years in much more pleasant surroundings.
 Barbier's early work, while at the Observatory, consists of over twenty memoirs and reports.
 We mentioned above his work with devising a new type of thermometer and Barbier wrote on this as well as on other aspects of instruments.
 After he was encouraged to undertake research in mathematics again by Bertrand, Barbier wrote over ten articles between the years 1882 and 1887.
Born 18 March 1839, St HilaireCottes, PasdeCalais, France. Died 28 January 1889, St Genest, Loire, France.
View full biography at MacTutor
Tags relevant for this person:
Astronomy
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References
Adapted from other CC BYSA 4.0 Sources:
 O’Connor, John J; Robertson, Edmund F: MacTutor History of Mathematics Archive