We study the case of contact angle hysteresis, when a solid defect isquasi-statically pulled out and pushed into a liquid, in the presence ofgravity. We solve the problem analytically in an approximation which, in thecase of a truncated parabolic pinning force becomes exact in the the limit ofslow variations in the height of the liquid vapour interface. The case of aGaussian pinning force is solved by a geometrical construction. We show thatthe extension of the defect, and not the capillary length, is the determininglength scale, when the extension of the defect is much smaller than thecapillary length.
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