<16 
Absorption of Phosphate of Lime ; and 
duc'dve of harm, or at the best does no gfood, in perhaps not a 
few instances ; and this may be due to the porosity and liifht 
character of some soils, in consequence of which the soUdjle 
phosphates are washed away by heavy rains, or suffer changes 
which render them ineffective. 
With a view of ascertaining whether this supposition is likely 
to be correct, I have carefully studied tlic changes which soluble 
phosphate undergoes, when brought into contact Avith various 
kinds cjf soils of known composition. 
The soils used in the following experiments were — 
A. A red loamy soil. 
jB. A calcareous soil. 
C. A stiff clay subsoil. 
D. A stiff clay surface-soil. 
E. A light sandy soil. 
F. A clay-marl. 
In the case of the first five soils a superphosphate was em- 
ployed, containing 37'20 per cent, of bone-earth rendered soluble 
by acid ; in the sixth experiment the superphosphate used con- 
tained 23 '84: per cent, of soluble phosphate. The superphos- 
phate was free from organic matter and salts of ammonia. 
Absorption of Soluhle Phosphate hj a Red Loamy Soil. 
Experiment A. — In the first set of experiments a deep, red 
loamy soil, well suited to turnips, was employed. This soil was 
found on anah sis to contain in 100 parts : — 
Moisture 2-05 
Organic matter anil water of comLiiiatii)!! .. .. (i-75 
Oxides of iron and alumina 6'10 
Carbonate of lime 1"22 
Alkalies and magnesia .. 1'20 
Insoluble siliceous matter (clay and sa'.ul) .. .. 82-22 
100-44 * 
5250 grains, or 12 oz. of this soil, were mixed with 109'34 
grains of superphosphate, containing 37'20 per cent, or 40 67 
grains, of bone-earth rendered soluble by acid, and the whole 
repeatedly shaken up in a Winchester st<)})pered bottle with 
1^ pint, or 13125 grains, of distilled water. After a lapse of 
twenty-four hours 3500 grains of tlie supernatant liquid were 
drawn off. The amount of bone-earth in this perfectly clear 
solution was next determined, and found to weigh 4"37 grains. 
The total amount of liquid (13,125 grains) consequentlv con- 
tained 16 38 grains of bone-earth ; and, deducting these 16 ;)8 
grains from 40'67 — the amount of soluble bone-earth originally 
