Vaison-la-Romaine, in the Vaucluse department, once had a hydraulic lime factory, the Eydoux factory, whose sign can still be seen on these buildings of the old town. The plant extended near the Ouvèze river and used its water. The purpose of the lime industry was to transform clay-rich limestone rocks into hydraulic binders. The conversion process took place through cooking in ovens where the previously crushed raw materials and mineral fuels were mixed. The cooking products were then quenched with water and ground into a powder that was then sifted and bagged.