A differential ebulliometric apparatus of the Swietoslawski type requiring ca. 10 cm(3) of sample is described. The application of this apparatus to the determination of enthalpies of vaporization was tested with cyclohexane and ethanol. The values obtained at 298.15 K were 33.1 +/- 0.5 kJ mol(-1) and 42.3 +/- 0.5 kJ mol(-1), for cyclohexane and ethanol, respectively, in good agreement with the corresponding values in the literature.