Paris, France/parisF499-table of afinities

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In an early attempt to raise the sophistication level of chemistry, Étienne François Geoffroy (1672-1731) constructed a "Table des Affinités." Geoffroy took his concept of "affinity" from Georg Ernst Stahl (1660-1734), the proponent of phlogiston, who believed a relative ordering of "affinities" (the order in which substances displaced each other from compounds) would allow the prediction of other chemical reaction outcomes. This concept of the affinity of one substance for another was an extension of the Newtonian idea of mutual gravitational attraction of physical bodies, and was taken seriously as late as the 19th century by Berthollet. The Table of Affinities identified substances by ancient alchemical symbols. Each substance at the top row heads a column which includes the substances in order of affinity, or displacement, as one moves down the column. For example, in the 4th column, top row, vitriolic acid (sulfuric acid) combines most rapidly with phlogiston, and then with alkali (potassium hydroxide), followed by volatile alkali (ammonia), the "absorbent earths," iron, copper, and silver.