‎"BERTHELOT, MARCELLIN. - FOUNDING THERMOCHEMISTRY.‎
‎Recherches de Thermochemie. Premiere-Troisieme Mémoire. (Sur la Chaleur dégagée dans les Réactions chimiques. - Sur les quantités de Chaleur dégagées dans la Formation des Composés organiques. - Sur la Chaleue animale). (3 papers).‎

‎Paris, Victor Masson et Fils, Imprimerie Gauthier-Villars, 1865. 8vo. Contemp. hcalf, raised bands, gilt spine. Light wear along edges. Small stamps on verso of titlepage. In ""Annales de Chimie et de Physique"", 4e Series - Tome VI. 512 pp. and 2 folded engraved plates. (The entire volume offered). Berthelot's papers: pp. 292-328, 329-441 a. pp. 442-464. Clean and fine.‎

Reference : 44099

‎First appearance of the three importent papers in which Berthelot founded the science of thermochemistry.""Bertholet enunciated the principle that the heat evolved or absorbed in a chemical change depends only on the initial and final states of the reactants and products, provided no external work is done. This is Bertholet's second principle analogous to Hess's law of constant heat summation. He based this principle on the assumption of an equivalence between internal work (le travail moleculaire) and heat changes in a chemical reaction (Bertholet's first principle).""(DSB II, p.69.).""In the 1860s Berthelot was done with synthesis and turned to thermochemistry, the study of the heat of chemical reactions. In some of his work he had unknowingly been anticipated by Hess, but he went much further. He devised a calorimeter within which he could measure the heat of chemical reactions and ran hundreds of determinations. This work along with that being conducted by Thomson threw the science of thermochemistry into high gear.""(Asimov).‎