‎"REGNAULT, V. (HENRI VICTOR) - THE VAPOUR PRESSURE OF STEAM.‎
‎Mémoire sur les Forces élastiques dela vapeur d'eau.‎

‎Paris, Victor Masson, 1844. No wrappers. Extracted from ""Annales de Chimie et de Physique"", 3me Series - Tome 11. Pp. 273-335 and 1 large folded engraved plate (apparatus). With the halftitlepage to volume 11.‎

Reference : 48079

‎First printing of an importent paper in which Regnault found the connection between vapour pressure of steam at different temperatures.Henri Victor Regnault improved the method of Dalton to measure the elastic force of vapours at saturation. At the boiling point of a liquid, the elastic force of its vapour is equal to the supported pressure. Thus, if one boils water in an enclosure under increasing pressure conditions, water will reach increasing boiling temperatures at the same time. For each case, the elastic force of vapour will be equal to the imposed pressure.‎