Relative transport fractions have been measured in the molten system silver nitrate - sodium nitrate at 330° over the range 5 to 25 mole% silver nitrate. The individual fractions for silver, sodium, and nitrate ion have been assessed within limits. The results indicate that transport by silver ion is greater than that by sodium ion at the same concentration, although the latter has the smaller radius. The usual assumption that the largest ion (nitrate) does not transport charge is within the interpretation of the results.