B C Sand-sized 物 particles Clay and silt- sIZed particles Pores +1/64 inch- Figure 1. A, Section through sand showing"packing"betwcen the grains B. Seetion through a loamy sand showing concentrations of elay and silt panicles at the points of contact between sand grains, reducing the size of the pores between the sand grains It is important to note that the clay and silt material itself possesses porosity due to very fine"packing"of pores between silt and clay particles. C. Section through a sandy loam showing a typical assembly of sand, silt, and clay particles into aggregates. Large pores exist primarily between aggregates and constitute a smaller proportion of the sail than in sand or loamy sand. As in B it is important to note that the clay and silt portion of this soil itself possesses orosi ty comprising much smaller pores than can be shown her