This paper presents the scientific project of Descartes’s Meteors (1637) and integrates it in the development of Descartes’s thought. It assesses Descartes’s publication strategies and the reception of the essay, while drawing attention on its opposition to contemporary Aristotelian meteorology. I argue that Descartes is concerned in The Meteors with advancing an anti-qualitative physics on the basis of an ontological reduction of real accidents to modes. I then analyses Descartes’s nominalist critique of the late-scholastic notion of body from Replies VI, The World and Rule XIV.