Abstract: The pressure gauge with a capsule formed by a cylindrical low cap sealed by a circular resilient membrane comprises, between this membrane and an indicating pointer, a kinematic linkage exclusively composed of three pairs of intermeshing gears. A spiral spring inserted under a small tension between the pointer shaft and a fixed stud takes up the lost motions of the gears thus maintaining a reliable connection between the membrane and the indicating pointer. Thanks to that linkage the ratio between the membrane deflections and the angular displacements of the pointer is rigorously linear. Furthermore, since the membrane deflections are directly proportional to the pressures in the capsule, the divisions of the dial graduation, which correspond to those pressures, are strictly equidistant.