In another connection, the anomalous behavior of very dilute aqueous salt solutions, notably potassium chloride and potassium chlorate, made it of interest to learn the viscosities of these solutions at low concentrations. The viscosity of aqueous KCl has been precisely measured by Joy and Wolfenden, but so far as we have found them, the recorded data onKClO3proved inadequate for our purpose. The viscosity has therefore been measured in the hope that a study of the variation of this property with the concentration might reveal a relationship enabling us to interpret our results in the prior study.