120 
On the Chemical Properties of Soils. 
Therefore '170 grains were removed from every 1000 j^rains of 
li(^ui{l of 8'o31 grains from the entire quantity of liquid used in 
the experiment and absorbed by 3500 grains of soil. 
Ammonia. 
Grains. 
1000 airains of this soil thus absorbed in the 2ncl Experiment -9457 
After having taken np in tlic Isfe Experiment .. .. '51 G 
Or in both experiments 1000 !j;rains of soil absorbed .. 1"5217 
Thus in each case the soils absorbed a considerable quantity of 
ammonia from the stronger solution with which they were brought 
into contact after having taken up a certain variable quantity 
from a weaker solution. 
It is singular that whilst the proportion of ammonia removed" 
by each of these five soils varied considerably in the first series 
of experiments with the weaker ammonia solution, the total 
(juantity of ammonia absorbed by ]000 grains of soil in both 
experiments is almost identical in four of the soils, and but little 
less in the remaining one. Thus the total amount of ammonia 
absorbed by 1000 grains of soil was in the case of the — 
Ammonia. 
(J rains. 
1. Calcareous soil 1\")193 
2. Fertile loamy soil 1-53G3 
3. Clay soil 1-1240 
4. Sterile sandy soil 1-5220 
5. Pastnre land 1-5217 
It will be seen that the soil from a permanent pasture absorbed 
much more ammonia in the 2nd Experiment than in the first, 
so that the total quantitv of ammonia absorbed in the two 
together is nearly identical with that absorbed by the other soils. 
I have shown that this soil contained much organic matter 
(humic acids), and that a portion of this organic matter united 
with ammonia passed into solution in the 1st Experiment, impart- 
ing to it a deep yellow colovn-. In the 2nd Experiment with a 
stronger ammonia solution the liquid was but little coloured. 
It appears thus that, comparatively speaking, little ammonia 
was fixed in the soil in the 1st Experiment, because the organic 
acids in this soil uniting with the ammonia of the weaker solu- 
tion, produced soluble combination before insoluble compounds 
of ammonia could be formed in the soil in as large a proportion 
as in the other soils containing much less organic matter. 
The organic acids of the pasture soil were apparently removed 
in the 1st Experiment, and thereby the soil acquired increased 
powers of absorbing ammonia from the stronger solution used in 
the 2nd Experiment. 
.. Thiu.d Series of Experiments. 
Although the preceding experiments show distinctly that soils, 
no matter of what character, absorb more ammonia from strong 
