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meas-ured on the pure components.Evidently, the acidic nature of one of the two absorbents is enhanced by the presence of the other. The nature of the interaction which brings about increased acidity has not been determined. Use can be made of this characteristic, however, to separate aliphatic amines, certain TV-substituted and ring substituted aromatic amines. The following general method is offered for the separation: Sample size and column length will have to be adjusted to the relative concentrations of the individual constituents.The sample is first dissolved in benzene and applied to a silicic acid column employing benzene as developer. Ar-Alkyl-substituted aromatic amines and certain ring-substituted aromatic amines pass into the filtrate while the aliphatic amines are held firmly near the top of the column. The filtrate is then concentrated by evaporation and introduced into a column of 50% by weight of boron oxide-silicic acid where the Ar-alkyl substituted aromatic amines remain at the top of the column and the ring substituted aromatic amines pass into the filtrate. The amines to which this method has been applied are:A*-alkyl-substituted aromatic amines-methylaniline, ethylaniline, dimethylaniline, and diethvlaniline.Ring-substituted aromatic amines-o-and p-nitroaniline, oand p-chloroaniline, and o-and p-methylaniline.Aliphatic amines-butylamine, amylamine, and decylamine.Those mixed adsorbents which share the adsorption of organic molecules, thus exhibiting R/ values intermediate between those measured on the pure adsorbents, should afford the practical chromatographer a wider choice of adsorbents.ACKNOW LEDGMENTThe authors wish to express their appreciation to the Phillips Petroleum Co., Bartlesville, Okla., for the generous financial grant under which this work was possible.

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