‎"CLAUSIUS, R. (RUDOLF) - ANNOUNCING THE ""TEOREM OF EQUIVALENCE""‎
‎Ueber die Anwendung des Satzes von der Aequivalenz der Verwandlungen auf die innere Arbeit. (Vorgelen in der Züricher naturforschenden Gesellschaft am 27. Januar 1862).‎

‎Leipzig, Johann Ambrosius Barth, 1862. Without wrappers. In ""Annalen der Physik und Chemie. Hrsg. von J.C. Poggendorff"", Bd. 116, No. 5. Pp. 1-192 a. 1 folded lithographed plate. (Entire issue offered). Clausius' paper: pp. 73-112. With titlepage to volume 116.‎

Reference : 45071

‎First appearance of the paper in which Clausius makes importent contributions to the generalization and understanding of the Second Law of Thermodynamics by introducing the concept of disgregation and proving the equivalence of the transformation of heat.""Clausius began that search for understanding in 1862 by introducing the concept of disgregation, a concept that, he said, was based on an idea he had long held: that the force of heat for performing mechanical work (both internal and external together) was proportional to the absolute temperature.13 Clausius had never stated this idea explicitly before, although he had argued in 1853, by adopting an analogy between a reversible steam engine and a thermocouple, that the potential difference at a thermocouple junction should be proportional to the absolute temperature. In any event, he now wished to assert that the work which can be done by heat in any change of the arrangement of a body is proportional to the absolute temperature multiplied by a function of molecular arrangement, the disgregation Z. Given this assumption and his postulate that the heat in a body H was only a function of temperature, he was able (1) to prove his theorem of the equivalence of transformations and (2) to separate the equivalence function (entropy) into a temperature-dependent term and a configurational-dependent term...""(DSB).The issue contains other notable papers, Plücker ""Ueber recurrente Ströme und ihre Anwendung zur Darstellung von Gasspectra"", pp. 27-54, Tyndall ""Ueber Strahlung und Absorption der Wärme durch gasförmige Materie"", pp. 1-27.‎