The original question was: I know that the buoyant force on an object equals the weight of the liquid that it displaces. If this is true, as I think it is, that an object has buoyancy even if there is no liquid directly below it, then where does the force come from? I have always imagined that buoyancy originates from particles of the higher density liquid pushing against the bottom of the submerged object. Although there is some mass being moved upward (the water) the net result is that more mass is moved lower, so the lead sinks. Buoyancy can also be derived in terms of the difference in pressures between the top and bottom of an object.