1861-1887. Part I to IV/1 bound in 7 volumes (all published). 4to (248 x 162 mm). ix , 766; viii, 744; iv (i.e. II), 1-250; iv, 251-490; II, 491-730; X, 731-837 ; II, 240 pp. Including half-title to part II, separate title-pages to parts I, II, and III/4, as called for, 3 plates in part II and several woodcut illustrations in part I and II. Part I and II bound in contemporary half calf with gilt-lettered spines (spines rubbed, extremities worn), parts III/1-4 and IV/1 in original printed wrappers and uncut, part III/1 largely unopened, some dust-soiling and minor chipping of wrappers, part IV/1 with old tape repair to spine. Text little age-toned, very minor occasional spotting, very light foxing to part III/1, a few pencil markings, two leaves in part I brown-stained, tear to p.39/40 of part III/1 not affecting text. Provenance: E. Börnstein (signature to first flyleaf in part I and II). All in all a near fine set, collated complete. ---- Duveen 316 (vols. I-II only); Partington IV, pp. 533-65; DSB VII, pp. 280-3; Norman 1205 (wrong title, incomplete, lacking parts III/2 to IV/1, and 2nd edition of parts I and II only). - FIRST EDITION OF ALL PARTS, exceptionally rare, of Kekulé's most important work. "In 1865, in a paper read before the Paris Chemical Society, Kekule announced his discovery of the ring structure of the benzene molecule, which had been revealed to him in his famous vision of long chains of carbon atoms twisting and curling like snakes in front of him until one gripped its own tail and whirled mockingly before his eyes" (Norman). August Kekulé was less a practical chemist than more a theorist with contributions sometimes very speculative, but in his art of discussing chemical formulas painted on a piece of filter paper, he inadvertently became an excellent teacher. His field of work was and remained the carbon chemistry and the elucidation of the constitution of aromatic compounds. In 1858 he recognized (simultaneously with A. S. Couper) the quadrivalent nature of carbon and the presence of carbon-carbon bonds. In 1864 he set up the benzene theory with which he explained the hitherto enigmatic structure of benzene as a symmetrical ring consisting of six carbon atoms. This theory immediately gained great interest and approval. Above all, it has well served the chemical industry in understanding complex carbon compounds. Many of his students also became professors or were successful in the chemical industry. Kekulé "was a key organizer of the 1860 Karlsruhe Congress, a meeting of European chemists where the present understanding of atomic weights was first agreed upon. In 1865 he published the first accurate analysis of the ring structure of benzene" (Duveen). This extensive but unfinished work is rarely found complete, as it took three decades to publish the four volumes with the first fascicle printed in June 1859 and the final fascicle IV/1 in 1887. - Visit our website for additional images and information.