The complete fatty acid composition of fats and oils can be readily determined by use of silicic acid – silver nitrate column chromatography in conjunction with gas–liquid chromatography, permanganate–periodate oxidation, hydrazine reduction, and infrared analysis. These techniques were used to demonstrate the occurrence of trans-5-hexadecenoic (2.6%) and trans-5,cis-9-octadecadienoic (4.6%) acids in the seed oil of Thalictrum venulosum. The oil contains two predominant and one minor system of fatty acids: (i) trans-5-hexadecenoic, trans-5-octadecenoic, trans-5,cis-9-octadecadienoic, trans-5,cis-9,cis-12-octadecatrienoic; (ii) cis-9-hexadecenoic, cis-9-octadecenoic, cis-9,cis-12-octadecadienoic, cis-9,cis-12,cis-15-octadecatrienoic; and (iii) cis-5-hexadecenoic, cis-5-octadecenoic, cis-5-eicosenoic.

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Several attempts have been made to modify the Kjeldaht method for determination of nitrogen in order to avoid the distillation. For example, Marcali and Rieman 1 use the formaldehyde method, and Harvey ~-determined nitrogen in unicellular algae on the submicro scale (5-30 #g) using a hypobromite titration. He showed that the mercury catalyst did not interfere in the titration. So far little use appears to have been made of Koltho//and Stenger's method a involving titration of ammonium salts with calcium hypoehlorite, hence a study has been made of its application to the Kjeldahl process a.The most likely interference in the titration would be the catalyst used in the digestion. Several were tried but all save mercury interfered, either because of their colour masking the endpoint or because they reacted with the titrant. Mercury did not interfere, and the precipitation of its oxide daring the addition of alkali is a useful indication of the approach of the neutrMisation point. Sodium hypochlorite was preferred as titrant because it is more readily available than the calcium salt. Tartrazine was used as indicator in the final titration with hypochlorite ~.The procedure has been used both on the micro and semimicro scale for a limited number of compounds. All those tried have yielded satisfactory results. When pre-reduction is necessary the direct titration is unapplicable, for all the reducing agents tried interfere with the end-point.It would be of advantage to carry out the digestion and titration in the same vessel, and various modified digestion vessels have been * We have great pleasure in dedicating this paper to our good friend Professor Dr. R. Strebinger on the occasion of his 70th birthday.

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