By the end of the 1820s, an innovative product was introduced in the northern Italian editorial market: technical and popular periodicals offering “useful knowledge” to a larger audience composed of members of the provincial middle-class, clergymen, and modestly educated craftsmen. By examining their medical content, this paper shows that popularisation did not merely entail disseminating a set of stable, unanimous, and trustworthy medical doctrines; rather, it represented a crucial step in the making of science during a period in which medical (...) theories were still various and contradictory. Moreover, it demonstrates that the environmental and preventative approach to disease, which these medical contributors often employed, did reflect recent developments in chemical or physical knowledge and responded to pedagogical and informative goals; but it mostly served to affirm the social usefulness of medicine and the legitimacy of health professionals' participation in determining how to regulate more general epidemiologic, social, and political issues. (shrink)