55 



the results listed as total nitrogen-in-the-nltrate-from-humin. 



The total nitrogen in the hydrolysate was determined by add- 

 ing the nitrogen obtained as ammonia, and humin (in salt and that 

 precipitated by calcium hydroxide) to the total nitrogen-in-the- 

 filtrate-from-humin. 



Fifteen grams of phosphotungstic acid were used for the pre- 

 cipitation of the bases. The barium phosphotungstate from the 

 sphagnum-covered peat retained 0.0055 gram nitrogen. The solu- 

 tion containing- the basic nitrogen was made to. 50 cc. vUim" '* ' 

 that containing the total nitrogen-in-the-filtrate-from-the-bases was 

 made to 250 cc. volume. 



The experimental data showing the grams of nitrogen and per 

 cent of total nitrogen are given in Table XIX. 



Table XIX. Nitrogen distribution in that portion of a sphagnum- 

 cohered peat soluble in 4 per cent sodium hydroxide and not precipi- 

 tated by hydrochloric acid and (in part) of a similar solution from a 

 calcareous black grass-peat. 



Sphagnum-covered 

 peat 



Cateareous 

 black grass-peat 



1 Calculated from one determination. Duplicate lost in digestion. 

 8 Distribution of the remaining nitrogen not determined. 



16. "Jodidi numbers." These determinations were carried 

 out as directed previously on Fargo clay loam, Fargo silt loam, 

 Hempstead silt loam, prairie-covered loess, and forest-covered 

 loess. 



The resulting data in grams and in per cent of total nitrogen 

 are shown in Tables XX, XXI, XXII, XXIII, and XXIV. The 

 figures for similar fracions from the complete Van Slyke analyses 

 are added for comparison. These results will be discussed later. 



