Some examinations were made on infrared absorption spectra of substances as adsorbed on silica gel or activated alumina in column chromatography. From the results obtained with several troponoid and aromatic compounds, it was found that the spectrum of the adsorbed substance can be obtained by measuring the adsorbent carrying the substance by the potassium bromide disk method when the amount adsorbed is comparatively large. This method will be useful for the identification of organic compounds and studies on the mode of their adsorption. Results obtained from some troponoid and aromatic compounds possessing hydroxyl, amino, or carbonyl as the functional group indicated that there is no drastic change in their spectra when using silica gel. Phenol adsorbed on alumina already showed the spectrum of Ph-O^- ion type. The ν(C=O) band of adsorbed ketones shifted to a lower frequency region
