The Paper describes further experiments carried out by the Author with an improved form of the apparatus previously described ("Proc." Ph. Soc., XXI., p. 374), by means of which the value of the coefficient of diffusion of salts through water can be found at various temperatures.Special flasks, similar to those already employed, were filled with the solution under investigation, and one was suspended from each arm of the balance in a large bath of distilled water maintained at constant temperatures in a thermostat room. The diffusion tubes of both flasks were of equal length, but their cross-sections differed considerably, and a method of differential weighing was used to compensate for any small changes in temperature.From the rate at which the flasks change in weight the value of the coefficient of diffusion of the salts is deduced. Figures are given for this value in the case of KCI and KNO₃ at various concentrations and at different temperatures, and from these figures the temperature coefficient of diffusion is found.