58 
Absorption of Phosphate of Lime ; and 
we should lose all the advantages resulting from equal distribu- 
tion of the phosphates and their incorporation with the soil. 
The more rapidly the soluble phosphates in superphosphate 
are precipitated or rendered insoluble in the soil, and the more 
viniformly these highly-divided insoluble phosphates are distri- 
buted in that portion of the surface-soil which is just under the 
young turnip-plant, the more energetic their effects. Superphos- 
phate acts a great deal more energetically when applied with the 
liquid than with the dry drill ; according to practical men, 
2 cwts. of superphosphate applied with water frequently produce 
as good an effect as 3 or 4 cwts. in a dry state, 
A little consideration will explain this difference. In the 
first place, superphosphate, in the shape of a powder, cannot be 
so uniformly distributed on the land as it is in a liquid condi- 
tion. In the next place, the acid or soluble phosphate may, and 
often does, remain unchanged in the soil for a long time when 
superphosphate is applied in a dry state, and no rain falls for 
some time, or the manure is badly prepared. In dry weather 
the soluble phosphate remains as such where it has been 
deposited ; when rain falls, as is frequently the case, in insuf- 
ficient quantity to dissolve the soluble phosphate and to produce 
at once a dilute solution, a proper distribution in the soil is 
not effected. In other words, there will be too much phosphate 
in one place and none in another. And, besides this, more or 
less acid phosphate will be left that cannot exert any beneficial 
effect on the young turnips. I have frequently picked up on 
fields bits of superphosphate a month or six weeks after its 
application, and found in them still a considerable proportion of 
acid or soluble phosphate of lime, notwithstanding that some 
rain had fallen during that time. There cannot, therefore, be 
much doubt that in superphosphate applied in a dry state fre- 
quently a large proportion of the phosphates remains inactive 
in the soil just at the period when phosphates are most needed by 
the young plants. 
On the other hand, if superphosphate mixed with a sufficient 
quantity of water is put on the land Avith the liquid-drill, the 
whole amount of the acid or soluble phosphate in the manure 
is at once brought into contacit with a portion of the surface-soil, 
and by it rapidly precipitated and changed into insoluble phos- 
phate. Appliecl with water, the manure thus is not only uni- 
formly distributed on the land, but its most valuable constituent 
is rapidly changed by the soil into the most active condition in 
which it can be presented to the young turnip-plants. 
We can thus readily explain the fact that in many instances 
2 cwts. of superphosphate produce as good a crop of swedes when 
