In De magnete, Gilbert frequently appealed to diagrams. As result of a focus on the experimental methodology of the treatise, its diagrammatic dimension has been overlooked in the scholarship. This paper argues that, in De magnete, at least some diagrams are epistemically relevant; specifically, Gilbert moves from experiments to concepts and theories through diagrams. To show this, I analyze the role that the “Diagram of motions in magnetick orbes” plays in the formulation of Gilbert's rule of alignment of magnetic bodies (...) within the orb of virtue. If it turns out that diagrams play a genuine role in Gilbert's magnetic investigations, then his investigative strategy goes beyond mere experimentalism. (shrink)