Abstract: A self-erecting tiltmeter includes a vertical seeking assembly suspended on a gimbals within a housing which contains a viscous fluid. Portions of the assembly outer surface spherically match corresponding portions the housing inner surface, leaving a gap or gaps across which the fluid may transfer tilts to the vertical seeking assembly. Different portions may have different radii or curvature. The fluid is sufficiently dense as to reduce the weight of the assembly on the gimbals. The vertical seeking assembly includes a conductivity difference bubble sensor assembly, signals from which are transmitted to the exterior of the housing through wires which pass through the pivots of the gimbals. An annulus of closed cell neoprene accommodates thermal expansion of the fluid.