114 



BULLETIN No. 145 



[April. 



17. Matter e Noire, CARBON, NITROGEN AND PHOSPHORUS IN THE 

 MATIERE NOIRE; RESULTS EXPRESSED AS POUNDS PER TWO 



MILLION POUNDS OF DRY SOIL. 

 (Soil not acid-extracted before treatment with ammonia) 



Phosphorus-nitrogen ratio == i '.6.9 

 Nitrogen-carbon ratio = i :6.6 

 Phosphorus-carbon ratio 1 145.6. 



The matier e noire was now redissolved in dilute ammonia, an 

 excess of i percent hydrochloric acid added and set aside over 

 night. The precipitate of organic matter was brought on to a filter 

 paper, which had previously been dried at uoC and weighed. 

 The precipitate was washed with i percent hydrochloric acid, dried 

 at noC and weighed. The precipitated matter e noire was obtained 

 in quantity and analyzed for carbon, nitrogen and phosphorus. The 

 results obtained are recorded in Table 18. 



TABLE 18. PERCIPITATED Matibre Noire, CARBON, NITROGEN AND PHOS- 

 PHORUS IN PRECIPITATED Mature Noire: RESULTS EXPRESSED AS 

 POUNDS PER Two MILLION POUNDS OF DRY SOIL 



(Soil not acid-extracted before treatment with ammonia) 



Phosphorus-nitrogen ratio = 1 132.4 

 Nitrogen-carbon ratio = 1 17 

 Phosphorus-carbon ratio == 1 1225 



The results recorded in Tables 17 and 18 are very significant 

 as can be more readily seen by glancing at Table 19 which sum- 

 marizes the above data. 



TABLE 19. Matiere Noire, CARBON, NITROGEN AND PHOSPHORUS PRECIPI- 

 TATED FROM AMMONIACAL SOLUTION BY HYDROCHLORIC ACID: RESULTS 

 EXPRESSED AS PERCENT OF TOTAL SOLUBLE IN AMMONIA. 

 (Soil not acid-extracted before treatment with ammonia) 



