lime a better fertilizer than phosphate of
lime?

What can you say of the _lasting manures_?]

_Bone ashes_, or bones burned to whiteness, may be similarly treated.
Indeed, in all of the forms of bones here described, the phosphate of
lime remains unaltered, as it is indestructible by heat; the differences
of composition are only in the admixture of organic constituents.

_The reason why super-phosphate of lime is so much better than
phosphate_, may be easily explained. The _phosphate_ is very _slowly_
soluble in water, and consequently furnishes food to plants slowly. A
piece of bone as large as a pea may lie in the soil for years without
being all consumed; consequently, it will be years before its value is
returned, and it pays no interest on its cost while lying there. The
_super-phosphate_ dissolves very _rapidly_ and furnishes food for plants
with equal facility; hence its much greater value as a manure.

It is true that the _phosphate_ is the most _lasting_ manure; but, once
for all, let us caution farmers against considering this a virtue in
mineral manures, or in organic manures either, when used on soils
containing the proper absorbents of ammonia. They are _lasting_, only
in proportion as they are _lazy_. Manures are worthless unless they are
in condition to be immediately used. The farmer who wishes his manures
to _last_ in the soil, and to lose their use, may be justly compared
with the _miser_, who buries his gold and silver in the ground for the
satisfaction of knowing that he owns it. It is an old and a true saying
that "a nimble sixpence is better than a slow shilling."

IMPROVED SUPER-PHOSPHATE OF LIME.

[What are the ingredients of the _improved_ super-phosphate of
lime?]

To show the manner in which super-phosphate of lime is perfected, and
rendered the best manure for general uses, which has yet been made,
containing large quantities of phosphoric acid and a good supply of
ammonia,--hereby covering the two leading deficiencies in a majority of
soils, it may be well to explain the composition of the _improved
super-phosphate of lime_ invented by Prof. Mapes.

This manure consists of the following ingredients in the proportions
named:--

100 lbs. bone-black (phosphate of lime and carbon).
56 " sulphuric acid.
36 " guano.
20 " sulphate of ammonia.

[Explain the uses of these different constituents.

What is nitrogenized phosphate?]

The sulphuric acid has the befo