The electrification phenomenon can be analysed from two points of view: 0 from that of the liquid. @ from that of the solid.Research into this phenomenon to date includes models presented by Helmholtz, Gouy-Chapman and Stern, but all of these base their analysis on a liquid viewpoint. Since electrification actually occurs at the solid-liquid interface, i t seems unlikely that analytical results based on this approach only will be sufficiently detailed. In the experiment reported here both the r potential of the solid and the streaming current are measured. In order to explain the experimental results a specific adsorption phenomenon is required. Therefore, this paper aims to study electrification simultaneously from both the solid and the liquid viewpoints.< 1 NTRODUCT ION> When a liquid with good insulating properties flows through a pipe, a current is observed. This current is called streaming current. A streaming current exists at a solid and liquid interface and the slipping plane potential exerts a great influence on the magnitude. Therefore i t becomes important to measure the potential of the slipping plane in order to investigate the electrification mechanism. A t present, two methods of analysis are used to explain the electrification phenomenon, namely an approach from the solid body and from the liquid body. In the former method changes are made in the liquid's electric conductivity, dielectric constant. liquid velocity etc. and conclusions are drawn from the electric charge volume measured. In the latter method the coarseness, material etc. of the pipe wall are varied and the resulting electric charge volume is taken. However, both of these methods look at the mechanism from only one side and this does not provide a sufficient basis for
