MANURING EXPERIMENTS WITH PADDY RICE (THIRD YEAR). 
Phosphoric 
acid taken 
Phosphoric acid in 
the dry matter of 
the whole crop. 
Phosphoric 
acid in the 
manure. 
up from the 
soil, resp. 
from soil & 
manure. 
' % 
grms. 
grms. 
grms. 
Unmanured, 
1889. .0.240 
0.64 
0 
0.55 
11 
1890. .0.165 
0.86 
0 
0.53 
11 
1891. .0.180 
0.80 
0 
0.73 
Without phosphoric acid, 
188g. .0.232 
0.61 
0 
0.52 
11 >♦ 11 
1890. .0.165 
0.88 
0 
0.55 
»• 11 11 
1891. .0.171 
0.96 
0 
0.89 
Complete manure, 
1889. .0.320 
4.12 
18.36 
4-°3 
»1 11 
1890. .0.206 
2-73 
18.36 
2.40 
11 11 
1891. .0.220 
2.62 
8 - 33 1 
2-55 
The figures for the phosphoric acid assimilated from the soil 
of the unmanured plots and those which had received all 
nutrients except phosphoric acid, indicate that the disintegra¬ 
tion and decomposition of the phosphatic constituents of the 
soil originally inaccessible to the roots, gradually commence on 
a rather large scale. Our soil is very rich in phosphoric acid 
(0.49%), but as it consists chiefly of recent volcanic products, it 
is not yet sufficiently decomposed to yield much of the latter 
nutrient to crops. The repeated mechanical treatment of the 
soil which had been left uncultivated for several years before the 
experiments were commenced, and the indirect action of the 
ammonium sulphate and potassium carbonate on the plots 
without phosphoric acid, are probably the principal reasons for 
the slight increase of the assimilability of the phosphatic soil 
ingredients. In the average of the three years the quantity of 
phosphoric acid consumed from the soil amounted to 0.60 grms. 
per frame=o.72 kilogrms. per tan on the unmanured plots, and 
to 0.65 grms. per frame = o.78 kilogrms. per tan on the plots 
4 As these plots had received in i8go a large dose of phosphoric ac'd we 
applied less of it in 1891. 
