“…Pyle and Jones (82) have also studied the effect of wetting agents on the physical properties of clay bodies. Elton (81) views the sedimentation method commonly used for determining particle size as a means of determin-RECENT reports have indicated a growing activity in the application of size reduction (107), in a more definite approach to basic principles (107,108), and in improvements in devices for size reduction (109). This year, all three of these fields have made further advances; and the relatively newer aspects of nucleation and soil conditioning have made their impact.…”