A modified visual method for determining the solubility of highly soluble salts in aqueous media up to 100° C is presented. The solubilities of NaCl, KCl, CaCl2, Na2SO4, and K2SO4 were determined up to 100° C. The tabulated experimental data and the fitted equations describing the data indicate that the previous literature data for the solubility of these salts were generally high by 0.05 to 2.0 weight percent salt.