抄録
Colloid chemical studies were pursued with the Taizanjino uncultivated top-soils which had been incubated for a conciderable time with organic material and calcium. In orignal-and not incubated top-soils, rich in humus, rotted products were hastened to be composed by drying. By this drying the soil seemed to be brought to have a min-value in pH-ζ curve. On the other hand, where incubated in the above way, the soils could have a min.-value in pH-ζ curve. We supposed that the created good humus gives these properties of matured soil to the incubated soils.
