St. Petersburg State University, Менделеевская линия, округ № 7, Saint Petersburg, Northwestern Federal District, 199034, RussiaRussian Chemical Society
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Wikipedia's[2][3] Dmitri Mendeleev article states it plainly: "On 6 March 1869, he made a formal presentation to the Russian Chemical Society, titled The Dependence between the Properties of the Atomic Weights of the Elements". Russia was still on the Julian calendar, so contemporary Russian sources date the work to February; the manuscript sheet on Commons is signed 17.02.1869, the Julian date for 1 March, and the pin uses the Gregorian date Wikipedia gives for the presentation itself.Dmitri Mendeleev's paper The Dependence between the Properties of the Atomic Weights of the Elements is read to the Russian Chemical Society in St Petersburg, arranging the known elements by atomic weight and valence and leaving gaps for elements not yet found.
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