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‎Indication de quelques-uns des résultats obtenus à Cocanada, pendent l'éclipse du mois d'août dernier, et à la suite de cette éclipse. (Cocanada, 19 septembre 1868).‎

‎(Paris, Mallet-Bachelier), 1868. 4to. No wrappers. In: ""Comptes Rendus Hebdomadaires des Séances de L'Academie des Sciences"", Tome 67, No 17. Pp. (813-) 852. (Entire issue offered). Janssen's paper: pp. 838-839. A few minor brownspots.‎

‎First apperance of of the paper in which Janssen announced the first observations of a Solar Prominence without Eclipse. ""Janssen and Sir Norman Lockyer independently and about the same time discovered the method of observing solar prominences and the limb of the sun through using a high dispersion spectroscope in order to project the bright hydrogen lines of the prominence spectrum on the much attenuated background of the solar spectrum."" (Shapley & Howarth ""A Source Book in Astronomy"", where this paper is translated on pp. 308-310).""This (the spectra of helium in the sun) was announced on the same day by the French astronomer Janssen, who was in India observing a total eclipse. As a result, the French government some ten years later struck a medallion showing the heads of both scientists.By that time, the two men had made a much more dramatic discovery at the same time, this time in cooperation. Janssen, studying the spectrum ofthe sun during the eclipse, had noted a fine line he did not recognize. he send a report on this to Lockyer, an acknowledges expert on solar spectra. Lockyer compared the reported position of the line with lines of known elements, concluding that it must belong to a yeat unknown element, possibly not even existing on the earth. He named the element, from the Greek word for the sun.""(Asimov).Parkinson ""Breakthroughs"" 1868 A.‎