VARIOUS PHOSPHATIC MANURES ON UPLAND SOIL. 
9 
and must both be considered to have the same very considerable 
manurial value (56). For their application on dry land, the 
conversion into steamed bone dust may be profitable in many 
cases also in Japan, as by this operation a very fine powder is 
obtained, which admits of a better distribution on the soil, and 
undergoes decomposition with great ease ; but we are inclined to 
recommend to the farmers racher a preparatory fermentation of the 
raw crushed bones in the compost bed whenever it is sought to 
accelerate the action of this manure.—The Thomas phosphate has 
almost exactly the same manurial value as the crude bone dust and 
raw bones; it decomposes a little more slowly in the soil than the 
two latter phosphates, and should therefore be always applied as 
early as possible.—The lowest effect was observed with the bone ash, 
which, owing to high temperature during the incineration of the raw 
bones, contains the phosphates in a very insoluble and partly fused 
state and should accordingly be converted into superphosphate 
before application. 
It affords moreover some interest to compare the results 
obtained with the above phosphates on upland soil with those 
previously found in our experiments with rice on irrigated paddy 
land. The principal figures of the two reries of experiments are 
the following : 
Dry land. Barley. Paddy field. Rice. 
Consumed lrom 
100 parts of phos¬ 
phoric acid. 
Relative 
manurial 
value. 
Consumed lrom 
100 parts of phos¬ 
phoric acid. 
Relative 
manurial 
value. 
Superphosphate... 
.21.5 
IOO 
24.I 
IOO 
Steamed bone dust , 
.16.6 
79 
14.2 
56 
Precipitated calcium 
phosphate. 13.8 
62 
25.1 
106 
Crude bone duste 
•. 12.4 
56 
14.6 
60 
Thomas phosphate 
. 131 
55 
13-7 
53 
Bone ash . 
. 5 ° 
27 
6.6 
28 
These figures show a pretty close coincidence as to the relative 
manurial values of the double superphosphate, crude bone dust, 
Thomas phosphate, and bone ash. From the phosphoric acid of 
these manures the barley consumed on the dry land a little less 
than the rice on the irrigated soil, probably because the former 
