The usefulness of mineral medicinal water as an effective therapeutic resource has been known and estimated since prehistoric times. In Spain, the attempt of territorial unification under King Ferdinand V and Isabella I sponsored the development of a national image through the inventory of their greatness and one of their important possessions were the mineral medicinal springs. The seventeenth-century scientific way of thinking, from alchemy to iatrochemistry, aimed at understanding the effect of these waters by basic analysis, hydromineral treatment although existent because of popular beliefs began to be regarded as a medical science. If the paper of Alfonso Limon Montero is considered the first major compilation of Spanish Springs, the unfinished paper from Bedoya and specially that of Juan de Dios Ayuda must be considered the systematic introduction of modern chemical analysis of Bergman and Fourcroy.