In the early decades of the seventeenth century, various attempts were made to develop a dynamical vocabulary on the basis of work in the practical mathematical disciplines, particularly statics and hydrostatics. The paper contrasts the Mechanica and Archimedean approaches, and within the latter compares conceptions of statics and hydrostatics and their possible extensions in the work of Stevin, Beeckman and Descartes. Descartes’ approach to hydrostatics, a discussion of which forms the core of the paper, is shown to be quite different (...) from that of his contemporaries, above all in its attempt to provide a natural-philosophical grounding for hydrostatics while at the same time using it to develop a range of concepts, approaches and ways of thinking through problems that would shape Descartes’ mature work in optics and cosmology.Author Keywords: Scientific revolution; René Descartes; Isaac Beeckman; Simon Stevin; History of mechanics; History of statics; History of optics. (shrink)