Answers were received from five chemists engaged in official work and three engaged 

 in commercial work, viz, Messrs. E. M. Bailey, New Haven, Conn.; F. B. Carpenter, 

 Richmond, Va., reporting work of Mr. W. D. Cooke; H. S. Lansdale, Buffalo, N. Y.; 

 C. B. Morrison, New Haven, Conn.; J. Bernard Robb, Richmond, Va.; B. F. Robert- 

 son, Clemson College, S. C.; Paul Rudnick, Chicago, 111., and T. C. Trescot, Wash- 

 ington, D. C. 



It is regretted that cooperation has not been more general, but the work required 

 seemed burdensome, and doubtless few could find the time to engage in it. Several 

 of the cooperating chemists, however, have shown extraordinary industry, reporting 

 an amount of work seldom equaled in voluntary investigation of this sort. The ques- 

 tions involved in the plan of work are not less than 14; hence analytical results 

 are too complicated to admit of convenient tabulation. It seems better, therefore, to 

 deduce from the analytical figures the answers to the several questions. 



Before judging the results it is well to bear in mind the reasonable expectation of 

 agreement or accuracy from a number of chemists working on the same subject. I ,ast 

 year on the simpler problem of determining nitrate-free nitrogen, the work of over 

 50 chemists, possibly the largest number of the association ever engaged on a single 

 question at one time, seems to indicate that about 98 per cent of the truth is the average 

 with present methods and present personnel. Then in the more difficult question of 

 nitrates and the separation of several forms of nitrogen, this expectation would seem 

 to be at least high enough. Thus methods for nitrates that give as much as 98 per cent 

 of theory are at least as accurate as the average results on nitrate-free substance. While 

 this limit may easily be exceeded by experienced and skillful individual analysts, it 

 is useless to deny that it is not exceeded by the average results. 



The analysts used chiefly as their source of nitrate nitrogen amounts of their own 

 standardized nitric acid containing from 28 to 160 rugs of nitrogen. The results obtained 

 are reported as percentages, the basis of which is the amount of nitrogen that should 

 have been obtained. 



The questions involved follow, with the answers deduced from the figures of the 

 several analysts. 



Percentages of nitrogen recorded based on amount present, using different methods. 

 [Is nitric acid, in the absence of organic matter, reduced to ammonia without loss?] 

 (1) BY METHOD (C). 



(2) BY METHOD (D). 



o Analytical work reported by F. W. Rudnick throughout the report was done by F. Fenger, K. J. Mon- 

 rad, and A. C. Johnson. 



