20 
MANURING EXPERIMENTS WITH PADDY RICE (SECOND YEAR). 
phoric acid, of which 24.80% was soluble in neutral citrate 
solution and 4.55% soluble in mineral acids. 
4) Peruvian guano, undissolved, containing 14.18% phos¬ 
phoric acid and 7.61% nitrogen. 
5) Thomas phosphate with 21.75% phosphoric acid and 75% 
fine powder of a diameter of 0.1 millimetres. 
6) Steamed hone dust containing 23.06% phosphoric acid, 
3.87% nitrogen, and 1.33% fat. The separation with 
chloroform showed that in 100 parts of the manure 0.94% 
of the nitrogen was not in the form of bony substance ; 
hence the proportion of nitrogen to phosphoric acid in the 
bony part was 1 : 7.9, showing that a considerable part of 
the gelatogenous substance had been extracted. 
7) Crude bone dust containing 19.70% phosphoric acid, 4.74% 
nitrogen and 1.93% fat. From 100 parts of the manure 
0.71% of nitrogen could be separated by chloroform as 
not belonging to the bony part ; hence the proportion of 
nitrogen to the phosphoric acid in the bony part was 1 : 
4.9, which enables us to conclude that no gelatogenous 
substance had been extracted from the bones. 
8) Bone ash containing 30.465% total phosphoric acid ; 4.89% 
phosphoric acid were dissolved by neutral citrate solution. 
9) Podolian phosphorite containing 35.02% total phosphoric 
acid ; 1.24% were dissolved by citrate solution. 
The mechanical condition of the manures No. 6—9 as 
determined with 
follows : 
a set of 
sieves with 
round 
holes, 
was as 
Diameter of the 
Steamed 
Crude 
Bone 
Phos¬ 
particles. 
bone dust, bone dust. 
ash. 
phorite. 
Less than 0.25 
millimetre. 
. 84-9 
37-8 
54-8 
93.° 
0.25—0.5 
1) 
.II.I 
25.2 
21.7 
6.9 
0.5—1 
)} 
. 4 -° 
35-9 
10.6 
0.1 
i —2 
If 
. — 
1.1 
12.9 
— 
The other manures used were ammonium solphate and 
potassium carbonate, of which equal quantities containing per 
