This paper presents the results of the study concerning to the leakage current be-haviour on artificially polluted ceramic insulator surface. From the present study it was observedthat there is a reasonably well-defined inception of current i.e. scintillations at a finite voltage.The corresponding voltages for extinction of the current are in the range of 0.8 kV to 2.1 kV.Obviously, the dry band formed in the immediate vicinity of the pin prevents smooth current flowas the voltage rises from zero. Only when the voltage is adequate it causes a flashover of the dryband and current starts flowing. As is common in similar current extinction phenomena, herealso, the extinction voltages are significantly lower than the inception voltages.Further, the voltage-current curves invariably show hysteresis - the leakage currents are lowerin the reducing portion of the voltage. This is obviously due to drying of the wet pollutantlayer thereby increasing its resistance. It is believed that this is the first time that such a directquantitative evidence of drying in individual half cycles is experimentally visualized.