Port Tobacco times, and Charles County advertiser. (Port Tobacco, Md.) 1845-1898, 1852-05-12

Notwithstanding The various compounds
value almost entirely depends on two Of
them. On the ammonia already present in
il as salt, with that which is capable of
teing formed by the decomposition of its
azolIzed matter, and On its phosphoric acid
or phosphates, which are combinations Of
this acid with some base. The small guam
!ity Of the other substances in it possess no
particular value, as they can, If needed, be
supplied much cheaper from other sources.
Does the value of guano depend on lis
ammonia which it already may have, or
which may be formed in it, and its phospho-
-fic acid or phosphates We have, in sup
port of this, a unity Of sentiment amongst the
abes! chemists. Liebig, Ure, Johnston, and
indeed nearly all who have written on the
subject, agree in the opinion that guano owes
lis value to its ammonia and phospha,es.-
These two substances must give guano its
value, or nothing else does, for, take a.
way these two, and only moiety of other
matters remains, which can be cheaply OBJ
ianed from many sources.
Not only are these substances the cause
of The value of guano, but as either may ex-
Isl IN greater or less proportion, in any PAL
tlcular specimen, it makes that specimen bet
Ter or worse for particular soils. Ammonia
is supplied 10 plants in large quantities from
the atmosphere, being absorbed by soils,
and, with iron and clay, forms "true salts"
Blu, if any particular soil has not this absor-
bent capacity, and has a deficiency Of iron
and clay, it cannot obtain ammonia from
the usual source of supply, and will be un-
productive, unless il be supplied from some
other source. If guano is used, then, the
purchaser should know which of the diff
ierent lots contains the most ammonia. But
many soils have the capacity 10 supply
themselves with ammonia, but are deficient
in phosphates, and therefore barren, and if
the owners Of soils find it more convenient
TO buy guano than any other manure, they
should know what specimen contains the
largest quantity Of phosphaes, wha. sam
piles contains the most Of what they want.
If The purchaser does not know, would he
not be constantly liable to loss in buying
the wrong specimen If il even acts well,
he is not assured that another specimen
would not have acted better. If, on his
land, in one year, he makes a luxurient crop,
by the use Of gnano. the next year by the
use of different specimen, even at the same
price, he may make a very inferior CROP
Guano, therefore, has relative value in re-
alion to particular soils, as it can supply
them with greater or less proportion Of
their deficiencies; it has an absolute value
depending on the quantity of ammonia which
is already, or can be formed in it, and on
lis phosphates Most clearly and unques-
tionably, then, It's inspection should show
the proportion of each Of these constituents,
so as to show its absolute worth, and lis
relative value to different soils. When a
farmer is buying guano, let him know how
much Of each valuable substance he may be
purchasing, then he will not be spending his
money without knowing what he is getting
for it, and can better suit his guano to his
particular soil. The proportion of the two
valuable substances is very variable, and yet
the guano, at present, has but two, or al most,
three grades of value.
(To be continued.)