Charles Janet

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Charles Janet

Charles Janet (born June 15, 1849 in Paris , † February 7, 1932 in Voisinlieu , Beauvais ) was a French engineer, factory manager, inventor and naturalist in various fields.

Life

Janet studied at the École des Arts et Manufactures de Paris and became an engineer. In 1877 he married the daughter Berthe of the wealthy brush factory owner Alphonse Dupont and ran the then well-known brush factory in Beauvais until he handed over the management in 1895. In 1924 he became president of Société Jean Dupont & Cie. He was not only a successful businessman, but also had a private interest in natural sciences and also studied at the Sorbonne , where he also received his doctorate. From 1882 he began to publish on scientific subjects (on the geology of the Paris basin).

Janet lived with his family (he had seven children, one of his sons was a well-known aviator during World War I) in a magnificent Villa des Roses in Beauvais (Voisinlieu), which formerly belonged to Paul Wallet, who painted Jean-Baptiste there from 1863 to 1865 Camille Corot , who among other things painted L'église de Marissel in the Louvre in the park . The villa stood empty for a long time after World War II when it was used by the German occupiers and was demolished in 1972.

plant

He is known for his left-step arrangement of the periodic table (Left-Step Table, after the rediscovery of his contributions around 2010). The publications on this, which took place from 1927, were privately printed and found only limited circulation, his only English publication on it did not adequately reflect his ideas. Originally, he arranged the elements as a helix on four nested cylinders. Using geometric transformations, he derived, among other things, the left-step arrangement, which later showed good agreement with the structure according to quantum mechanics (structure principle with Madelung's rule) - whereby in reality anomalies with this rule occur that the system does not describe. In contrast to the usual arrangements of the periodic table, he placed the s blocks on the right, then the p, d and f blocks to the left. Each column corresponded to a constant value of the sum of the principal quantum number and angular momentum. After him there were no elements beyond 120.

He speculated about an element made of two neutrons that he put in the place of zero, and a mirror image of the whole system with negative numbering ( antimatter ). He also predicted deuterium , with his system originating before the discovery of antimatter, deuterium, or neutron.

Twenty years before Glenn Seaborg he also recognized that the 7th period contained as many elements as the 6th period and that the lanthanides in the 6th period corresponded to the actinides in the 7th period.

In biology, he took photographs of microscopic images and studied the morphology of the heads of wasps, bees and ants, dealt with bees and ants in general, but also freshwater algae, with botany and published on evolutionary theory. As an inventor, for example, he made glass boxes that allowed a clear view of the interior of ant colonies and attracted a great deal of attention. In 1899 he became president of the French Zoological Society.

His publications comprise around 4000 pages with 700 illustrations. Janet also studied geology and paleontology. He had a collection of around 50,000 fossils and natural objects that were scattered after his death.

Periodic Table of Janet

Fonts

  • The structure du noyau de l'atome considérée dans la classification périodique des Eléments Chimiques, Imprimerie Départementale de l'Oise, Beauvais, 1927.
  • Concordance de l'arrangement quantique de base des électrons planétaires des atomes avec la classification scalariforme hélicoıdale des elements chimiques, Beauvais Imprimerie Départementale de l'Oise, Beauvais, 1930.

literature

  • L. Casson: Notice biographique sur la vie et de l'oeuvre de Charles Janet , Bulletin de la sociét'académique de l'Oise, Beauvais 2008, p. 232
  • Eric Scerri : A Tale of Seven Scientists, and a New Philosophy of Science , Oxford University Press, New York, 2016, pp. 149–170
  • Edward G. Mazurs : Graphic Representations of the Periodic System during One Hundred Years , University of Alabama Press 1974
  • Philip Stewart: Charles Janet: unrecognized genius of the Periodic System , Foundations of Chemistry, Volume 12, 2010, pp. 5-15
  • Johan Bollin, Edward O. Wilson : Social insect histology from the 19th century: the magnificent pioneer sections of Charles Janet, in: Arthropod Structure and Development, Volume 37, 2008, pp. 163-167

Web links

Individual evidence

  1. ^ Janet, The helicoidal classification of the elements, Chemical News, June 1929
personal data
SURNAME Janet, Charles
BRIEF DESCRIPTION French engineer, factory manager, inventor, entomologist and chemist
DATE OF BIRTH June 15, 1849
PLACE OF BIRTH Paris
DATE OF DEATH February 7, 1932
Place of death Voisinlieu