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For the separation of beryllium, magnesium, calcium, strontium and barium by paper chromatography, a solvent- mixture, which is claimed to be superior to any previously devised for these elements, is described. This solvent -mixture may be used for a qualitative and semi -quantitative analysis of a mixture of these cations. A method is described, whereby micromole amounts of magnesium and the alkaline earths, separated by paper chromatography, may be titrated spectrophótometrically with di- sodium di- hydrogen ethylene diamine tetra -acetate reagent. The method should be Particularly useful for the analysis of Group IIA elements in a material of which no more than 5 mg. is available. The application of the classical methods of analysis to such a sample would be very difficult if they could be applied at all. A solvent -mixture is described for the qualitative and semi -quantitative analysis of a mixture of alkali metal and ammonium salts. Although all six cations are not separated on the one chromatogram, selective spraying reagents make such an analysis possible. Methods are also suggested for the quantitative determination of potassium, rubidium and caesium, after their separation by paper chromatography. A solvent- mixture for the qualitative analysis of mixtures of the Group IIIB elements and certain aluminium alloys, is proposed. It is worth noting that the whole analysis for the detection and semi- quantitative estimation of the ten metals in Groups IA and IIA has been carried out on 0.03 ml. of solution containing never more than 20 FM of cations (i.e. < 3 mg.). 0.01 FE amounts of any of these cations, with the exception of lithium for which 0.25 FM is required, can be separated and detected in a mixture of 10 FM of the cations in the same group. The results of certain of these researches have been published in the 'Analyst' in a paper entitled, "The Separation of Group IIA Elements of the Periodic Table by Paper Chromatography". A reprint of the paper is enclosed. Another paper entitled, "Chromatographic Separations in phenol - Methanol - Hydrochloric Acid Solvents; with special reference to Alkali Metals" will shortly appear in the 'Analyst'.