Leipzig: Johann Ambrosius Barth, 1893. 1st Edition. FIRST EDITION, FIRST PRESENTATION OF HELMHOLTZ’S DISPERSION THEORY OF LIGHT, THE BELIEF “THAT BOTH CONDUCTING AND DIELECTRIC MEDIA CONSIST OF MOLECULES, each comprising (in the simplest case) two oppositely charged atoms” (Maxwell’s Electro-magnetic Theory of Light, 375).
Helmholtz based his dispersion theory of light on what he called his “electrochemical theory.” Helmholtz believed that “identifying units of electricity with units of chemical affinity implied… the idea of ‘compounds in which every unit of affinity of every atom is connected with one and only one other unit of another atom’. This, he pointed out, ‘is the modern chemical theory of quantivalence, comprising all the saturated compounds” (ibid; Faraday, Conception of Electricity, 303). Item #578
CONDITION & DETAILS: Leipzig: Johann Ambrosius Barth. 8vo. (8 x 5 inches; 200mm x 125mm); Handsomely rebound in three-quarter calf over marbled paper boards (with purposeful scuffing to impart age -- see image); four raised bands at the spine; gilt-lettered and tooled. Very tightly bound. Ex-libris with stamp on title page and no exterior marks whatsoever; very light age toning; one plate split at the fold (not related to a paper of import). Very good condition overall.