88 



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



(10) BY METHOD (D). 



[Is any of the nitrogen in nitrate-free and ammonia-free nitrogenous bodies obtained?] 



(11) BY METHOD (G). 



o These figures were obtained distilling with magnesia only. Soda being added and distillation con- 

 tinued, the following additional percentages were obtained: Bailey, 8.3 to 9.3, average 8.8; Morrison, 8.3 

 to 11, average 9.7. These four determinations were made on cotton-seed meal containing 0.0739 gram of 

 nitrogen, on which nitrogen the percentages are based. 



(12) BY METHOD (F). 



Bailey and Morrison, who alone worked on this question, report that distillation was 

 rendered impossible by excessive frothing. 



[How complete is the liberation of ammonia when distilled with magnesia?} 



(13) BY METHOD (D). 



a These figures represent the fraction of total ammonia liberated by magnesia, the complement lacking 

 to make 100 per cent having been liberated by soda. Thus, Cooke's lowest result was 19 per cent distilled 

 from magnesia and the remaining 18 per cent was obtained by adding soda solution and continuing the 

 distillation. Trescot, reported below, recovered practically all of the ammonia by magnesia alone. 



(14) Is the loss of nitrogen by methods (c) and (d) caused by heat generated in mixing the 



acid and water f 



Rudnick, using potassium nitrate instead of a solution of nitric acid, obtained the 

 following figures, and as compared with these results those found with the solution of 

 nitric acid by the same methods averaged 79.8 to 66.1 per cent. Trescot obtained 

 80 per cent when using nitric acid, as compared with 100 per cent with potassium 

 nitrate. 



Rudnick' 's results, using potassium nitrate. 



