An approach for investigating the microstructural features that govern the capillary-pressure driven infiltration of liquid within beds of particles has been developed. Simultaneous measurement of the rate of liquid mass uptake and the volume occupied by that liquid within the particle bed provides information about the fraction of pore volume that participates in liquid infiltration as well as the effective size of the geometric unit that governs infiltration kinetics. Experiments involving the infiltration of squalane within different grades of silica and titanium dioxide illustrate the technique. The method is sensitive enough to enable interpretation of how variations in the morphology of the particles comprising the bed, or small changes in packing density within the particle bed, can lead to large changes in infiltration behavior. (C) 2012 Elsevier B.V. All rights reserved.