THE extent to which the Kjeldahl method has been applied to organic analysis has led to the publication of many data. From time to time, reviews (14,16, 66) have been published covering both macro-and micromethods. Comprehensive reports on microchemical methods have been made by Willits and Ogg (71, 72). In a previous paper (9), the method was reviewed from its inception to 1939. This report covers the period from 1939 to