Skip to main navigation menu Skip to main content Skip to site footer
logo

Essays

Vol. 158 No. 2 (2025): Rendiconti. Mathematics and Natural Sciences Class

Joseph Vallot and Pierre Janssen. A scientific and mountaineering adventure between 1890 and 1906 on Mont Blanc

  • Gian Sacchi Landriani
DOI
https://doi.org/10.3280/rndoa2025oa21158
Submitted
ottobre 1, 2025
Published
2026-02-17

Abstract

The story described has as its protagonist Mr. von Vlady, chief engineer of the Milan company Filotecnica located in Piazza Ellittica, producer of precision optical instruments. This character was taken as a point of connection to narrate the contemporaneity of two important figures in the decade between the 19th century and the following in the scientific and mountaineering fields: the meteorologist Joseph Vallot (Société botanique and Société géologique de France) and the astronomer Pierre Janssen (Académie de sciences and Director de Observatoire de Meudon). When reading this note, we are reminded of the great difficulties at the time of installing two observation shelters on Mont Blanc.

References

  1. Bignami G. (1978). La scienza “fin-de-siècle” in alta quota. Gli osservatori del M. Bianco. In: «Rivista del Club Alpino Italiano».
  2. Id. (2012). L’esplorazione dello spazio (Lezione tenuta nel 1998 presso l’Istituto Lombardo Accademia di Scienze e Lettere di Milano). Milano: Istituto Lombardo Accademia di Scienze e Lettere.
  3. Janssen P.J.C. (1892). Note sur observatoire au Mont Blanc. In: «Comptes Rendus Acc. Sc. Paris», XII.
  4. Malherbe J.M. (1987). Les observatoires du Mont-Blanc en 1900. In: «L’Astronomie», 101: 115-133.
  5. Id. (2022). Jules Janssen, The birth of solar physics, the foundation of Meudon Observatory and the Mont Blanc adventure (1875-1895). Paris: Observatoire de Paris-Université Paris Sciences et Lettres (PSL), HAL-03961607.
  6. Millochau G. (1906). La grande Lunette de l’Observatoire du Mont-Blanc. In: «La Nature».
  7. Sacchi Landriani G. (1988). L’osservatorio Janssen al Monte Bianco e i contributi di Eiffel e Vaudremer alla sua realizzazione (Conférence présentée à l’Ecole Nationale des Ponts et Chaussées, Paris). Milano: Politecnico.
  8. Id. (2005). La vetrina di Piazza Ellittica. Milano: Melusine