Polozheniya... is the first edition of the masters thesis by Dmitri Mendeleev. Published in 1856, it is a treatise on molecular volumes of various compounds. More importantly, it is a preview of the work this 22-year-old Russian scientist would go on to accomplish in the years ahead. Mendeleev would create the periodic table of elements fundamental to chemistry 13 years later. Item 136. $12,000.

Item 82 is a first edition of Galileo Galilei's Dialogo... Published in 1632. Galileo's ideas are presented in the form of a dialogue between advocates of the traditional Earth-centered solar system and the controversial Copernican model, which placed the sun at its center. Galileo would be condemned as a heretic for adopting the sun-centered model and be forced to repudiate his beliefs. Church doctrine interpreted such Biblical events as Joshua calling on the sun (not the Earth) to stand still as proof that the sun revolved around the Earth. $95,000.

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