me is often necessary for other purposes; and setting
aside, for the present, its feeding action, we will examine its various
effects on the mechanical and chemical condition of the soil.

1. It corrects acidity (sourness).

2. It hastens the decomposition of the organic matter in the soil.

3. It causes the mineral particles of the soil to crumble.

4. By producing the above effects, it prepares the constituents of the
soil for assimilation by plants.

5. It is _said_ to exhaust the soil, but it does so in a very desirable
manner, the injurious effects of which may be easily avoided.

[How does lime correct them?

How does it affect animal manures in the soil?]

1. The decomposition of organic matter in the soil, often produces
acids which makes the land _sour_, and cause it to produce sorrel and
other weeds, which interfere with the healthy growth of crops. Lime is
an _alkali_, and if applied to soils suffering from sourness, it will
unite with the acids, and neutralize them, so that they will no longer
be injurious.

2. We have before stated that lime is a decomposing agent, and hastens
the rotting of muck and other organic matter. It has the same effect on
the organic parts of the soil, and causes them to be resolved into the
gases and minerals of which they are formed. It has this effect,
especially, on organic matters containing _nitrogen_, causing them to
throw off ammonia; consequently, it liberates this gas from the animal
manures in the soil.

3. Various inorganic compounds in the soil are so affected by lime, that
they lose their power of holding together, and crumble, or are reduced
to finer particles, while some of their constituents are rendered
soluble. One way in which this is accomplished is by the action of the
lime on the silica contained in these compounds, forming the silicate of
lime. This crumbling effect improves the mechanical as well as the
chemical condition of the soil.

4. We are now enabled to see how lime prepares the constituents of the
soil for the use of plants.

[Inorganic compounds?

How does lime prepare the constituents of the soil for use?

What can you say of the remark that lime exhausts the organic matter in
the soil?]

By its action on the roots, buried stubble, and other organic matter in
the soil, it causes them to be decomposed, and to give up many of their
gaseous and inorganic constituents for the use of roots. In this manner
the organic matter is prepar