A continuous-flow-type liquid-liquid equilibrium apparatus has been designed, constructed, and used to measure the mutual solubilities of hydrocarbon + water systems. New results for benzene + water have been determined in the temperature range of 303-373 K at pressures within 1 bar of the three-phase curve. The results compare favorably with the literature values in the 303-333 K temperature range. The solubility of benzene in water matches the lower range of the high-temperature data (373-473 K). The relative errors in both liquid-phase compositions are less than 6% for all values. For benzene + water, the mutual solubility is correlated and used to estimate enthalpies of solution of benzene’ in water and water in benzene; results are in good agreement with literature values based on calorimetric measurements.