Abstract: A self-correcting autocalibrating analyzer for the direct determination of liquid vapor pressure and determination of the temperature at which a given ratio of vapor to liquid will exert a predetermined pressure in a container of predetermined volume. Test volumes within the analyzer can be automatically calibrated, and corrections for dissolved air in the liquid sample and/or for temperature-related changes in the liquid sample size can be made. The analyzer can set an alarm when unprogrammed variation is detected in preset volumes or when successive vapor pressure determinations of standard liquids vary by more than a predetermined amount.