Abstract: A column and detector are disclosed for two-dimensional column chromatography of a sample, in which the sample is injected close to a corner of a thin parallelepipedal column through which percolates a first solvent pumped at a controlled velocity. After a convenient time this flow is stopped and a stream of a second solvent is pumped at a controlled velocity in the perpendicular direction. Elution of the separated components is performed, the stream exiting from the column flows over a detector which monitors its composition at a large number of points, along the exit edge allowing the derivation of a two-dimensional chromatogram.