Lévy, Serve-Dieu Abailard (Called Armand)

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Lévy, Serve-Dieu Abailard (Called Armand)

(b. Paris, France, 14 November 1795; d. le Pecq, near Saint-Germain, France, 29 July 1841),

mineralogy.

Lévy’s father, a Florentine Jew, was an itinerant merchant who, on one of his trips to France, married a Parisian Catholic, Céline Mailfert. Their son’s birth records bear the unusual given names Serve-Dieu Abailard, which also appear on his death certificate, but Lévy called himself, more simply, Armand. It is under this name that he appears on the membership list of the Geological Society of London, beginning in 1824.

Lévy completed his secondary studies in Paris, at the Lycée Henri IV, and won the concours général in mathematics, a competition for the best students from all French lycées and collèges. He passed the entrance examination for the École Normale Supérieure in 1813 and graduated in 1816 with the title of agrégé in mathematical sciences. As it was difficult for a Jew to obtain a university position in France, he decided to leave the country and accept the post of professor at the Collège Royal of Ile Bourbon (now Ile de la Réunion) in the Indian Ocean. He embarked at Rochefort in 1818; the vessel was shipwrecked near Plymouth, an event that determined Lévy’s scientific career. For the next two years he supported himself by giving mathematics lessons and in 1820 met a rich mineral merchant, Henry Heuland, who had just sold a large collection of minerals to Charles Hampden Turner. Lévy was hired to make an inventory of it and to produce a descriptive catalog. In 1822, in London, he married Harriet Drewet, who was nineteen; they had several children.

In 1827 the work for which Heuland had commissioned Lévy was finished; and it was decided that, for reasons of economy, the catalog would be printed in Belgium. Lévy therefore moved to Brussels to supervise the printing of the text and the engraving of the illustrations. He was also appointed reader at the University of Liège, teaching analytical mechanics, astronomy, crystallography, and mineralogy. On 3 April 1830 he was elected a member of the Académie des Sciences et Belles-lettres of Brussels. After the July Revolution of 1830 he returned to Paris as a lecturer in mathematics at the École Normale Supérieure and professor at the Collège Royal Charlemagne (1831).

A short while after his return to France, Lévy’s wife dead. In 1838 he married Amélie Rodriguez Henriquez, the sister of his close friend, the mathematician Olinde Rodriquez. They had two daughters, the elder of whom married Alexandre Bertrand, curator of the Musée de Saint-Germain and brother of the mathematician Joseph Bertrand.

Lévy was a man of great frankness and exquisite politeness. If he was sometimes touchy, even with his friends, it was because he had been the object of racial and religious prejudice. During his stay in England, Lévy became friendly with Wollaston and Herschel, and he was member of the council of the Geological Society of London from 1826 to 1828. In France he had powerful defenders in Arago, Poisson, Charles Dupin, and the mineralogists Brochant, Brongniart, and Beudant. Des Cloizeaux considered himself Lévy’s student. Lévy died of a ruptured aneurysm at the age of forty-five.

Lévy became a mineralogist apparently by necessity rather than by vocation. While a student at the École Normale Supérieure, he undoubtedly took the mineralogy courses given by Haüy. He used the latter’s methods and perfected his system of notation in the illustrations of the Heuland collection catalog. The Haüy-Lévy notation or, as it is sometimes called, the Lévy crystallographic notation is still used.

From a morphological point of view, a crystal is characterized by its “primitive form,” a parallelepiped the symmetry of which represents the symmetry of the crystal. Haüy had shown that all the plane surfaces of a crystal can be envisaged as “rational truncations” on the vertices and edges of the primitive solid. Lévy designated the vertices by vowels, the edges by consonants, and the planes by these vowels and consonants modified by a coefficient (a simple fraction) indicating their slope. For example, all the vertices of the cube are designated by the letter a, and the regular octahedron, which derives from the cube, by a¹. It is easy to pass from Lévy’s notation to the crystallographic notation devised by W. H. Miller, which is now in general use.

In describing the Heuland collection and in measuring surface angles of its specimens with a goniometer, Lévy discovered important new mineral species: forsterite, babingtonite, brochanite, roselite, brookite, herschelite, phillipsite and beudaniitc. He also gave precise descriptions of the crystalline forms of eudialyte, wagnerite, and euclase. In addition, he named several minerals that were subsequently recognized as varieties of previously described species: turnerite, a variety of monazite; bucklandite, a variety of allanite; Königite, a variety of brochantite; mohsite, a variety of ilmenite; and humboldtite, a variety of datolite.

While studying the zinc-bearing minerals of La Vieille-Montagne, in Belgium, Lévy discovered an important new zinc silicate which he named willemite. The results of his research were published posthumously in the Annales des mines (1843) through the efforts of Des Cloizeaux.