In his influential Geographia generalis (1650), Bernard Varenius discussed Descartes’s explanation of the ebb and flow of the sea, pointing out that “both his words and his diagram” (Cartesii tam verba… quam diagramma) failed to agree with the observed phenomena. This double criticism captures well the attitude of several early-modern authors, who in commenting, criticizing, defending, or teaching Galileo’s and Descartes’s respective explanations of the tides paid particular attention to the accompanying figures. This lecture will document how these early-modern authors reproduced, modified, reinterpreted, or suppressed Galileo’s and Descartes’s original diagrams of the tides, in order to emphasize, solve, or hide the evident mismatch between the explanans and explananda.