Treats the new and rapidly developing independent field in gas chromatographic analysis based on the use of out of column phase equilibria and partition coefficients in gas-liquid systems. Describes new methods of head space analysis for the first time, plus related methods based on the equilibrium between liquid and gas states. Describes physico-chemical applications of this new method. Considers new principles of investigating chemical equilibria solutions and describes the determination of impurities in gases and the calibration of chromatographs. Covers original devices and up-to-date automatic instruments for head-space analysis.