Gabriel Delafosse

from Wikipedia, the free encyclopedia
Gabriel Delafosse

Gabriel Delafosse (born February 24, 1796 in Saint-Quentin , † October 13, 1878 in Paris ) was a French mineralogist and crystallographer .

life and work

Delafosse was the son of a provincial official, went to school in Saint-Quentin and Reims and studied at the École normal supérieure (ENS). He was one of the last pupils of the famous crystallographer René Just Haüy at the Muséum national d'histoire naturelle (Natural History Museum), became his assistant in 1816 and published his textbook on mineralogy (1822/23, 2nd edition, posthumous) and crystallography (1822) . In 1817 he became an assistant mineralogist at the Natural History Museum. In 1826 he became Maitre de conference at the ENS. In 1840 he received his doctorate in mineralogy and in 1841 professor of mineralogy at the Sorbonne (Faculté des Sciences) as successor to François Sulpice Beudant and on the former chair of Haüy. In 1857 he became professor of mineralogy at the Natural History Museum as the successor to Armand Dufrénoy .

Delafosse recognized that in crystallography the building blocks from which the crystals were built up in geometric crystallography had to be differentiated from natural molecules (the geometric building block could also correspond to several molecules). In this context, he investigated substances with similar crystals, but different chemical compositions. He thus plays a role in the development of the concept of the crystal lattice and occupies an intermediate position between Haüy as the founder of geometric crystallography and Auguste Bravais as the creator of the crystal lattice theory. He was also able to explain the asymmetry properties of crystals (hemihedral properties). Louis Pasteur was one of his students , and like him, he studied molecular asymmetry. He investigated the relationship between physical (electrical, optical, thermal) properties of crystals and their crystal shape.

He wrote a textbook on mineralogy that appeared from 1858. In 1867 he published his report on the development of mineralogy in France.

From 1857 he was a member of the Academie des Sciences . He was a founding member of the French Geological Society.

Charles Friedel named in his honor in 1873, the copper - iron - oxide Delafossit .

Delafosse wrote articles for the Dictionnaire universel d'histoire naturelle by Charles Henry Dessalines d'Orbigny (13 volumes and atlas, Paris 1841 to 1849) and was its co-editor. He was also editor of the Bulletin des sciences naturelles et de géologie (1824-1831) by Baron André Étienne d'Audebert de Férussac . He also published school books on science.

Fonts

  • Précis élémentaire d'histoire naturelle, à l'usage des collèges et des maisons d 'éducation, 4 volumes, Paris, Hachette 1830 and more.
  • Notions élémentaires d'histoire naturelle, 3 volumes, Paris 1835–1836 and more often.
  • Lecons d'histoire naturelle, Paris, 1838.
  • De la structure des cristaux, considérés comme base de la distinction et de la classification des systèmes cristallins. Sur l'importance de l'étude de la symétrie dans les différentes branches de l'Histoire naturelle, et en particulier dans la morphologie végétale et animale, Thèse de sciences, Université de Paris, 1840.
  • Recherches sur la crystallisation, considérée sous les rapports physiques et mathematiques, in: Mémoires présentées par divers savants à l'Académie royale des sciences de l'Institut de France, Volume 8, 1843, pp. 641-690.
  • Mémoire sur une relation importante qui se manifeste, en certains cas, entre la composition atomique et la forme cristalline et sur une nouvelle application du rôle que joue la silice dans les combinaisons minérales, in: Mémoires présentées par divers savants à l'Académie royale des sciences de l'Institut de France, Volume 13, 1852, pp. 542-579.
  • Mémoire sur le plésiomorphisme des espèces minérales, Paris, 1851 (extract in Comptes rendus de l'Académie des sciences, Volume 32, 1851, pp. 535-539).
  • Mémoire sur la structure des cristaux et ses rapports avec les propriétés physiques et chimiques, Comptes rendus, Volume 43, 1856, pp. 958-962.
  • Sur la véritable nature de l'hémiédrie et sur ses rapports avec les propriétés physiques des cristaux, Comptes rendus, Volume 44, 1857, pp. 229-233.
  • Mémoire sur l'électricité des minéraux, Annales des mines, Volume 3, 1818, pp. 209-226.
  • Nouveau cours de minéralogie, 3 volumes, Paris 1858 to 1862.
  • Rapport sur les progresses de la minéralogie, in: Recueil de rapports sur les progresses des lettres et des sciences en France, Paris, 1867.

literature

  • Kenneth L. Taylor: Delafosse, Gabriel, in Dictionary of Scientific Biography
  • Hans-Werner Schütt: The French mineralogy and the crystal structure theory by Gabriel Delafosse, Sudhoffs Archiv, Volume 69, 1985, pp. 1-7, JSTOR
  • Charles Friedel: La vie et la travaux de Delafosse, Rev. Sci., Volume 21, 1878, pp. 481-484

Web links

Individual evidence

  1. ↑ Hans-Werner Schütt, Sudhoffs Archiv, Volume 69, 1985, p. 1.
  2. ↑ Mineral Atlas
personal data
SURNAME Delafosse, Gabriel
BRIEF DESCRIPTION French mineralogist and crystallographer
DATE OF BIRTH February 24, 1796
PLACE OF BIRTH Saint-Quentin
DATE OF DEATH October 13, 1878
Place of death Paris