With the production of certain types of highly resistant layers in some glasses, increases of current with time are observed, similar to those reported qualitatively by several earlier investigators. The nature of these current increases have been studied quantitatively and found to follow, for the cases here studied, the relationship, log (Im—It) =loga1—b1t,whereImis the maximum value of the current,Itis the current at any timetafter application of the field, anda1andb1are constants. The timeTfor the current to reach its maximum value seems related to the applied voltage by the equationT=K1/V—K2. The values of the constantsK1andK2seem to decrease with increase in temperature. The time for the current to reach its maximum value decreases rapidly with increase in glass temperature. The possible importance of the phenomena observed in an explanation of the processes involved in the conductivity of glass is suggested, and the need for further investigation is emphasized. No theoretical explanation is given because of the apparent necessity for further investigations.