For some time, buffers made from triethylamine have been used in ion-exchange chromatography and electrophoresis at this Institute. Trimethyl-ammonium salts may serve the same purpose, but we have found the triethylammonium salts preferable since triethylamiDe, due to its higher boiling point, is more convenient to handle and is easier to purify than is trimethylamine. Triethylammonium formate, acetate, bicarbonate and carbonate are all volatile and cover the approximate pH. ranges 3-6 and 7-12. In many respects these buffers are superior to all volatile buffers used so far (pyrid-inium1, collidinium2 and ammonium8 acetates and formates). They have the following advantages : (1) They can be removed by lyophilization. (2) "Ultraviolet absorption can be measured without prior removal of the buffer. (3) A number of reactions proceed without complications in the presence of these buffers. Particularly noteworthy is the fact that little or no interference takes place in the ninhydrin reaction cording to Moore and Stein4 when aliquots of -0-5 ml. of column fractions are taken if the entration of the amine is 0*1 N or less. Much larger amounts of the amine may cause too high blank values (possibly due to traces of impurities). Disturbing background colour also results on paper containing triethylammonium buffer when the paper is strongly heated. (4) They are stable towards oxidation (collidinium salts are anodically oxidized). It is obvious that much time and labour may be saved when these buffers can be used for fractionation of mixtures containing both ninhydrin-positive and ultra-violet absorbing material. Excellent fractiona-tions of mixtures of amino-acids, in free and bound form, and purine and pyrimidine compounds have been obtained on 'Dowex 50' by the use of triethylammonium formate and acetate.