Ionic conductivities in hydrated sodium silicate gels (water glasses) of SiO2/Na2O 3.41:1 mole ratio have been obtained by impedance spectroscopy at temperatures above and below the thermally determined glass transition temperature. Conductivities at T. are in the range 10(-6) to 10(-7) S cm(-1), which are similar to those found recently in several kinds of polymer electrolyte. It is suggested that the absence of a mixed alkali effect and a strong dependence on water imply that conductivities are largely protonic in nature and involve strong interactions between protons, water molecules and the silicate framework.