Une lettre inédite de sir William Ramsay sur la découverte de l'argon

In July 1894, Sir William Ramsay sent to the French Academy of Sciences a 'pacquet scellé', registered under number 5038. This letter, which remained unknown until June 2004, expresses for the first time the idea of a novel chemical element occurring in the air. The final proof was given one year later by Lord Rayleigh and Ramsay, who gave it the name argon. To cite this article: Y. Jeannin, C.R. Chimie 8 (2005).