Abstract: Based on the error equation of ebulliometry: the t-xo line measured by a ebulliometer has the best approximation of the bubble-point line t-x when the circulation is set on the pseudo-static state where the condensate reflux diminishes to zero (r = 0). In this paper, the principle and realization of the method are further studied from different points of view, and three newly designed ebulliometers with pump stirrer are shown. The functions of the new ebulliometers and the reliability of the method are tested through experiments done in different concentration ranges and in different ways.