Recently, it has been suggested that Darcy's Law might not be applicable for modelling miscible, density-dependent flow in porous media. To investigate this, three sets of careful laboratory column experiments were performed on coarse and medium sands, consisting of upward displacement of water by sodium chloride solutions with concentrations ranging from 5 to 200 g/l. This paper is about these experiments. In this paper, the applicability of Darcy's Law was tested using a simplified approach that treated the interface between the (displaced) fresh and (displacing) salty solutions as being sharp.