uck should not be used immediately after being taken from the swamp, as
it is then almost always _sour_, and is liable to produce sorrel. Its
_sourness_ is due to _acids_ which it contains, and these must be
rectified by the application of an alkali, or by long exposure to the
weather, before the muck is suitable for use.

LIME AND SALT MIXTURE.

[What proportions of lime and salt are required for the
decomposing mixture?

Explain the process of making it.

Why should it be made under cover?]

The lime and salt mixture, used in the decomposition of muck, is made in
the following manner:

RECIPE.--Take _three_ bushels of shell lime, _hot from the kiln_, or as
fresh as possible, and slake it with water in which _one_ bushel of salt
has been dissolved.

Care must be taken to use only so much water as is necessary to dissolve
the salt, as it is difficult to induce the lime to absorb a larger
quantity.

In dissolving the salt, it is well to hang it in a basket in the upper
part of the water, as the salt water will immediately settle towards the
bottom (being heavier), and allow the freshest water to be nearest to
the salt. In this way, the salt may be all dissolved, and thus make the
brine used to slake the lime. It may be necessary to apply the brine at
intervals of a day or two, and to stir the mass often, as the amount of
water is too great to be readily absorbed.

This mixture should be made under cover, as, if exposed, it would obtain
moisture from rain or dew, which would prevent the use of all the
brine. Another objection to its exposure to the weather is its great
liability to be washed away by rains. It should be at least ten days old
before being used, and would probably be improved by an age of three or
four months, as the chemical changes it undergoes will require some time
to be completed.

[Explain the character of this mixture as represented in the
diagram. (Black board.)]

The character of this mixture may be best described by the following
diagram:--

We have originally--

+----------------------------------+
| |
Lime-+ Salt
| consisting of
| +---Chlorine } Chloride
| | and } of
| | +-Sodium. } Sodium.
| | | --Carbonic acid
| | | and
|