In the majority of forms of counter-current extraction column, the very small drop necessary to quickly reach equilibrium, and therefore to achieve productivity high, cannot be used due to the problem of preventing it from going in the wrong direction. In the case of the solid, however, for any rational particle size, a filter will prevent it from moving in an undesirable direction. Consideration of these facts led us to attempt to absorb water into silica gel, etc., and then use the water-saturated solid as one phase of a chromatogram, the other being a non miscible with water, the silica simply acting as a mechanical support. to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an original essay. This type of chromatographic division is therefore based on differences in the distribution between two liquid phases of the substances to be divided, and not, as in all chromatograms described previously, on differences in absorption between liquid and solid phases. The difficulties of using the chromatogram have been reduced when the substances to be separated are made visible by coloring. Different techniques have been used for this purpose (cf. Zechmeister & Cholnoky, 1936; Cook, 1941), although none of them was suitable for our problems. Since the substances we wanted to separate were acids and one of our phases is water, we were able to obtain visual evidence of the presence of one of these acids by adding an appropriate indicator to the water with which the gel was saturated. In the present paper, we introduce an approximate theory of chromatographic separation and describe an application of the new chromatogram to the microdetermination of the higher monoamino acid in protein hydrolysates. This technique is based on the separation of acetamino acids between the chloroform and aqueous phases, and replaces the macro-method described by us (Martin & Sygne, 1941,1), being rapid and economical both in materials and in equipment. progress, using ethyl acetate as the least polar phase in the chromatogram, on the separation of acetylated derivatives of most other natural amino acids, and the technique promises to be also useful in analogous separations of peptides simple. We would like to emphasize, however, that the possible areas of utility of the new chromatogram are by no means limited to protein chemistry. Using appropriate phase pairs, many other substances should be separable. When water is suitable as one of the phases, an indicator can be used to make the separation of organic acids or bases visible. Even when this is not possible, such as for neutral substances, the theory given below will reduce the known partition coefficient. In the usual adsorption chromatogram, optically active adsorbents have been used for optical resolutions (cf. Henderson & Rule, 1937; Karagunis & Coumoulus, 1938), and the resolution of racemic substances can be expected in the new chromatogram when the Either phase is optically active (cf. Bailey & Hass, 1941). The mobile phase may not be a liquid but may be a vapor. We show below that the contact efficiency between phases (theoretical plates per unit column length) is much better in the chromatogram than in normal distillation or extraction columns. Very specific separations of volatile substances should therefore be possible in a column in which permanent gas is circulated over a gel impregnated with a non-volatile solvent in which the substances to be separated obey approximately., 1937).