Unpublished manuscript, 'Mémoire sur la cause immédiate de la chaleur, de la pesanteur, généralement de tous phénomènes de l'ordre physique' [On the cause of heat, gravity, and generally of all phenomena of the physical order] by Azais This paper concerns states of matter and the causes of physical phenomena. Azais explains how external forces transform solid substances into liquids, vapours, gases and volatile fluids. Subject: Physics / Physical chemistry 1838