This paper investigates the relation between Gabriel Plattes’ cosmology and theory of matter, on the one hand, and his method of experimentation, on the other. In my view Plattes based his cosmology and theory of matter on specific “principles of nature” expressed as alchemical qualitative relations between bodies, and these principles formed the theoretical framework for his experimental method and technologies. I also claim that Plattes’ method of experimentation has heuristic purposes, acting as a tool to instantiate and illustrate these (...) natural principles. By quantifiable manipulations of matter, Plattes made use of experimentation to provide technologies whose immediate purpose was to ameliorate or improve the material world. (shrink)