Spectres Prismatiques et en Longueurs d'Ondes destinés aux Recherches de Chimie Minérale

Abstract

THE spectrum maps of Kirchhoff, Huggins, Angstrom, and Thalen are so complete that little has been left for later observers except the filling up of some details. Angstrom's discovery that the bright lines which form the spectrum of the electric spark are partly due to the air or other gaseous medium traversed by the spark, partly to the vapour of the metallic poles, formed an epoch in the history of spectrum analysis; and the publication of the fine map of the solar spectrum by Kirchhoff (founded on the great original work of Fraunhofer), in which the positions of a large number of the metallic lines are carefully laid down, gave a great impulse to the pursuit of this branch of physical science. For the discovery of the new metals, caesium, rubidium, thallium, and indium, we are indebted to spectroscopic analysis. In a paper communicated to the Royal Society in 1863, Mr. Huggins gave a valuable map of the bright lines of the metals, as seen through a system of prisms adjusted for a minimum deviation of the line D of Fraunhofer. This was followed by the works of Thalen and Mascart in which the positions of the metal lines are given in wave-lengths. The results obtained by Thalen are incorporated in the great work of Angstrom on the solar spectrum. Spectres Prismatiques et en Longueurs d'Ondes destines aux Recherches de Chimie Minerale. Par M. Lecoq de Boisbaudran, avec Atlas des Spectres. (Paris: Gauthier-Villars, 1874).