53 



with 4 per cent sodium hydroxide and filled to the mark. These 

 were thoroughly shaken and placed on their sides, thus allowing 

 the peat to settle on the sides of the cylinder, thereby exposing a 

 very large surface to the action of the hydroxide. The shaking was 

 repeated at intervals for nine days. The cylinders were then thor- 

 oughly shaken, placed in a vertical position and allowed to settle 

 for four days before the supernatant liquid was syphoned off and 

 filtered. The samples of calcareous black grass-peat were almost 

 completely dissolved by the hydroxide solution. 



These filtered solutions were neutralized with hydrochloric 

 acid (solution tested faintly acid) when a brown flocculent precipi- 

 tate separated. This was allowed to settle for several hours and 

 the cider colored solution syphoned off. The brownish black pre- 

 cipitates were filtered and after draining over night were thoroughly 

 mixed with a large volume of water and again filtered and drained. 

 The resulting precipitates were hydrolyzed with 200 cc. of hydro- 

 chloric acid for 48 hours. This amount of concentrated acid was 

 added and the flask brought to boiling until hydrogen chloride 

 fumes were evolved showing the presence of constant boiling acid. 

 Silicic acid separated on the condenser during the hydrolysis of 

 calcareous black grass-peat. Even after the hydrolysis there still 

 remained some small lumps of the "humus" precipitate. 



The entire hydrolysate was used for the ammonia determina- 

 tion. After this determination the "humin" precipitate was thor- 

 oughly ground in a mortar to insure complete disintegration, al- 

 though this seemed hardly necessary as the solid was already in 

 a fairly fine state of division. This precipitate was washed in the 

 usual manner by decantation, the filtrate concentrated by evapora- 

 tion and made to 250 cc. volume. Duplicate portions of 25 cc. 

 were used for the determination of total nitrogen in the solution 

 and the result listed as total nitrogen-in-the-filtrate-from-humin. 

 The remaining 200 cc. portion was used for precipitation of the 

 bases and subsequent analysis. 



The high content of carbonaceous organic matter made the 

 "humin" precipitate very difficult to digest. The sulfuric acid 

 required was 120 cc. and the digestion extended over 10 days be- 

 fore complete decoloration was effected. Of course precautions 

 were taken to prevent the absorption of ammonia from outside 

 sources, The material was diluted to 500 cc. and 250 cc. portions 

 used in the distillation. The basic nitrogen was precipitated with 

 25 grams of phosphotungstic acid. The nitrogen retained by the 

 barium phosphotungstate was 0.0043 gram. The solution contain- 

 ing the basic nitrogen was made to 50 cc. volume, and that con- 

 taining the total nitrogcn-in-the-filtrate-from-the-bases was made 

 to a volume of 250 cc. 



The experimental data showing the grams of nitrogen and per 

 cent of total nitrogen are given in Table XVIII. 



