MANURING EXPERIMENTS WITH PADDY RICE (SECOND YEAR). 
2 5 
for comparison the relative effect on the increase of hulled 
grain.* 
Relative 
Relative 
Relative 
assim- 
action 
manurial 
ilability. 
on the increase 
of hulled 
grain. 
value in the 
first season. 
Double superphosphate 
...IOO 
IOO 
IOO 
Precipitated phosphate 
... I04.O 
I07.1 
IO« 
Crude bone dust 
... 60.4 
59 - 8 
60 
Steamed bone dust ... 
... 58.6 
53 -o 
56 
Thomas phosphate 
... 56.9 
48.8 
s:t 
Sodium phosphate ... 
45-3 
50.2 
4S 
Peruvian guano 
... 34.4 
33-3 
34 
Bone ash. 
... 27.4 
29.1 
as 
Phosphorite . 
... 7.t 
11.8 
0 
There is a most satisfactory coincidence in the relative as- 
similability of the various phosphates and their relative action 
on the increase of hulled grain. The average of the two series 
of results given above in the 3rd column, constitutes ac¬ 
cordingly the standard for the calculation of the quantities of 
the various phosphates suited for rice under conditions similar 
to ours in respect to soil and climate. 
Before we consider the relative effect of the various phos¬ 
phates on crops we may quote here the results obtained by 
P. Wagner 10 on dry land in cylindrical pots of a diameter of 
and height of 20 centimetres. With moderate doses similar 
to ours he obtained in the average of three closely coinciding 
series of parallel experiments with wheat, barley, and flax, 
the following results as to the relative effects, that of the 
soluble phosphoric acid in superphosphates being reckoned as 
100 : 
* The figures of the following table differ slightly from those given by 
me in a lecture before the Agricultural Society of Japan, because in the latter 
case the small amount of dust adhering to the full grain had not been taken 
into account. 
10 Wagner, Thomas phosphate powder, 1887, p. 23. 
