The Model 1250 volumetric Pressure Plate Extractor is precision extractor designed so that the outflow section of the instrument is stable dimensionally. When the extractor is used in conjunction with the Hysteresis Attachments, the volume of water removed from the sample at each increasing pressure step can be accurately measured and retained. When pressure values are subsequently reduced, the volume of water that returns to the soil can then also be accurately measured. By this means, one can investigate the hysteresis properties of the soil. The Volumetric Pressure Plate Extractor in conjunction with the Hysteresis Attachments also makes it possible to measure the capillary conductivity of soils. The extractor can, of course, be used for any routine moisture extraction work on disturbed samples or undisturbed soil cores.