336 



Journal of Agricultural Research 



Vol. XVIII, No. 6 



Table VII. — Relative acidity of water-free composts 5 to 10 



[Expressed in cubic centimeters of Nlso sodium hydroxid required to neutralize 

 100 gm. water-free compost] 



1917 



Dec. 27 



1918 



Jan. 22 



Feb. 28 



Mar. 27 



May 3 



June 24 



Aug. 24 



1919 

 May 6 



Heated. 



Stirred. 



No. 5, 

 soil and 

 rock phos- 

 phate. 



1.80 



2. 40 



4. 00 



4. 60 



15. 00 



13. 60 



II. 60 



8.50 



No. 6, 



soil, rock 



phosphate, 



and sulphur. 



13.80 



52. 00 



108. 60 



175. 60 



385- 60 



I, 363. 00 



906. 02 



Not stirred. 



No. 7, 

 soil and 

 rock phos- 

 phate. 



1.80 



4. 00 



5.00 

 4. 60 



4.99 



No. 8, 

 soil, rock 



phos- 

 phate, and 

 sulphur. 



13.60 



01. 00 

 365. 00 



191.36 



Cold, stirred. 



No. 9, 

 soil and 

 rock phos- 

 phate. 



1.80 



3.00 



10. 60 



7. 60 



5-73 



No. 10, 



soil, rock 



phosphate, 



and sulphur. 



2. 60 



64. 60 



225. 60 

 760. 60 



I, 151. 26 



Table VIII. — Percentage of water-soluble and ammonium-citrate-soluble phosphorus 

 in water-free composts 5 to 10 



Jan. 22. . 

 Feb. 25. 

 Mar. 26. 

 Apr. 30. 

 Jtme 19. 

 Aug. 21 . 

 26. 

 Oct. II., 



Jan. 24. 

 Apr. IS. 



Date. 



1918. 



Percentage of total phos- 

 phorus 



Maximum percentage of 

 total phosphorus made 

 soluble 



Heated. 



Stirred. 



No. s, soil 



and rock 



phosphate. 



. 012 

 . 012 

 .008 

 . 012 

 .018 

 .010 



.007 

 9-576 





is 

 II 



0.063 



. 104 

 .108 

 . 112 

 .094 

 , 121 

 • 123 



. 126 



• 337 



9.576 



No. 6, soil, 

 rock phos- 

 phate, and 

 sulphur. 



.036 

 . 009 

 ■ ois 

 . 040 

 .118 

 •42s 



• 774 

 9. I 



E3 

 3 3 





0.063 



■ IIS 

 . 126 

 •151 

 .174 

 •378 

 I. 054 



I. 183 



1.874 

 2. 532 



Not stirred. 



No. 7, soil 



and rock 



phosphate. 



.011 

 . 017 

 . 012 



26. 9 



. 007 



9-S-6 



63 

 s a 



"51 

 B ca 



0.063 



•324 

 9. 576 



No. 8, soil, 

 rock phos- 

 phate, and 

 sulphur. 



• 199 

 9. I 



as 



a a 



0.063 



• 139 



• 356 

 ■ 416 



.638 

 1. 029 



Cold, stirred. 



No. 9, soil 



and rock 



phosphate. 



No. 10, soil, 

 rock phos- 

 phate, and 

 sulphur. 



. 010 

 . 020 

 . 014 



63 

 a a 



E "! 



1-5 



< o 



0.063 

 .114 



. 120 



.124 



. 140 



.166 



.012 .305 

 9.576 9.576 



• 023 



.014 



.065 

 .294 



.984 

 9. 1 



tin 



0.063 



• 113 

 .142 



• 733 



•975 



1.644 



2.582 



9.184 



