Background

François S. Beudant was born on September 5, 1787, in Paris, France.

Education

Beudant was educated at the École Polytechnique and the École Normale Supérieure in Paris.

Career

Beudant began his career as répétiteur at the École Normale Supérieure, leaving this post to become a professor of mathematics at the lycée of Avignon (1811) and then a professor of physics at Marseilles (1813). During these years his primary interests were zoology and paleontology, tastes he acquired while studying with Gilet de Laumont. He studied species of coelenterates and mollusks, trying to determine whether freshwater varieties could adapt to saltwater and whether marine forms could have originated from freshwater fauna. Some of his observations were included in "Mémoire sur la possibilité de faire vivre des mollusques fluviatiles dans les eaux salées et des mollusques marins dans les eaux douces…"

Louis XVIII appointed Beudant as assistant director of his cabinet of mineralogy in 1814, charging him with the task of cataloging the enormous mineralogical collection of the Comte de Bournon, which was to be moved to Paris from England the following year. This work directed Beudant’s attention from natural history to mineralogy and geology, with which he was thereafter concerned. In 1818 he was sent by the state on a scientific expedition to Hungary, where he gathered masses of important data that were published in his three-volume Voyage minéralogique et geólogique en Hongrie (1822).

In 1820 François Beudant became a professor of mineralogy and physics on the Faculty of Sciences at the University of Paris (known as the Sorbonne) but resigned the chair of physics so that Ampàre might have it. In 1839 he left the university and became inspecteur général des études, which was equivalent to being a supervisor for the entire French educational system. He held this position until his death. In 1841 he wrote a grammar of the French language that was favorably received by his contemporaries.

Mineralogical investigations, particularly experiments with carbonates and other salts, revealed to Beudant a principle of the combination of mineral substances that he expressed in Beudant’s law. Essentially, he found that some compounds dissolved in the same solution would precipitate together, forming a crystal whose properties they determined in common. The interfacial angles of this new crystal would have a value intermediate between the angles of the original compounds, proportional to the quantity of each. The same idea had been put forth by Robert Boyle in "The Origine of Form and Qualities" (1666). Beudant was rather conservative about the generality of his proposition, although Delafosse enthusiastically maintained that it should apply to all crystals. The generalization of this idea, the law of isomorphism, was proposed by Mitscherlich in 1819.

François Sulpice Beudant died on December 10, 1850, in Paris, Ile-de-France, France.

Achievements

• François Sulpice Beudant is remembered as mineralogist and geologist, who investigated the connections between chemical composition and crystal forms, which led him to a new system of classification for minerals. He also described many new kinds of minerals.
  
  The mineral beudantite was named for him.

Works

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  • Travels in Hungary, in 1818 1823
  • Elements of Geology: Prepared for the Use of Schools and Colleges
  • Traite Elementaire de Physique 1824
  • Notions Préliminaires De Géologie 1854
  • Traité Élémentaire De Minéralogie, Volume 1 1832
  • Traité Élémentaire De Minéralogie, Volume 2

Membership

François Sulpice Beudant was a member of the Bavarian Academy of Sciences and Humanities, the Hungarian Academy of Sciences and the Academy of Sciences Leopoldina.

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  In 1824, François Beudant became a member of the French Academy of Sciences.

  French Academy of Sciences , France

  1824

Connections

In 1821, François Beudant married Marie-Hélène Gratienne, by whom he had two sons.

Wife:

Marie-Hélène Beudant (Gratienne)

Son:

Amédée Louis Beudant

Son:

Léon Charles Anatole Beudant