A new current measurement method has been developed, allowing the determination of electrical characteristics on the water surface in the absence of or in the presence of monolayers. This work is concerned with the study of the surfaces of pure water and of acidic, basic and neutral ionic solutions. From the current versus time curves, i = f(t), the dipole density at the water surface has been calculated. On the other hand, the equation of the curve i = f(t) has been worked out. The theoretical result is in good agreement with the experimental one. In all cases a considerable decrease of the surface charge is observed for high ionic strength.