they cause the
ammonia to be thrown off and lost.

[From what other sources may potash be obtained?

How may we obtain soda?

In what quantities should pure salt be applied to the soil?]

_Potash sparlings_, or the refuse of potash warehouses, is an excellent
manure for lands deficient in this constituent.

_Potash marl_, such as is found in New Jersey, contains a large
proportion of potash, and is an excellent application to soils requiring
it.

_Feldspar_, _kaolin_, and other minerals containing potash, are, in some
localities, to be obtained in sufficient quantities to be used for
manurial purposes.

_Granite_ contains potash, and if it can be crushed (as is the case with
some of the softer kinds,) it serves a very good purpose.

SODA.

[If applied in large quantities will it produce permanent
injury?

In what quantities should salt be applied to composts? To asparagus?]

_Soda_, the requirement of which is occasioned by the same causes as
create a deficiency of potash, and all of the other ingredients of
vegetable ashes, may be very readily supplied by the use of _common
salt_ (chloride of sodium), which consists of about one half sodium (the
base of soda). The best way to use salt is in the lime and salt mixture,
previously described, or as a direct application to the soil. If too
much salt be given to the soil it will kill any plant. In small
quantities, however, it is highly beneficial, and if _six bushels per
acre_ be sown broadcast over the land, to be carried in by rains and
dews, it will not only destroy many insects (grubs, worms, etc.), but
will, after decomposing and becoming chlorine and soda, prove an
excellent manure. Salt, even in quantities large enough to denude the
soil of all vegetation, is never _permanently_ injurious. After the
first year, it becomes resolved into its constituents, and furnishes
chlorine and soda to plants, without injuring them. One bushel of salt
in each cord of compost will not only hasten the decomposition of the
manures, but will kill all seeds and grubs--a very desirable effect.
While small quantities of salt in a compost heap are beneficial, too
much (as when applied to the soil) is positively injurious, as it
arrests decomposition; fairly _pickles_ the manures, and prevents them
from rotting.

[What is generally the best way to use salt?

What is nitrate of soda?

What plants contain lime?]

For _asparagus_, which is a marine plant, salt is an exc