GRAIN-SIZE ANALYSIS BY BUOYANCY METHOD

A new routine experiment referred to as buoyancy analysis is proposed to determine the grain-size distribution of fine-grained sons. The buo yancy analysis is based on the sedimentation principles of the hydrome ter and pipette analyses. It determines the percent by weight finer th an a given grain size by measuring the buoyant weight of a 2.5-cm-diam eter sphere immersed in the soil suspension. The buoyancy analysis is slightly more accurate than the hydrometer analysis, has a shorter dur ation, and its readings can be fed directly into a computer. It yields results identical to those of the hydrometer analysis when the sphere is immersed within the depth range of the hydrometer bulb.