Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1884-05-16
An Easy Lesson in Agricultural Chem
iatry,

istry.
All intelligent farmers who use artiicially
prepared fertilizers will desire 10 understand
as far as possible the philosophy of their &C
tion. But what is more practical, and vastly
easier to understand is the chemistry Of their
composition. At this season, when immense
quantities of fertilizers are being used, the
easy lesson on their composition, which fol-
lows, is timely;
1t is fact that on worn out or partially
worn-out soils something is gone that was once
there, and which made the crops grow and
yield well. What these things are (for there
are more than one), has been found out by
the study and experiments of agricultural
chemists. This knowledge is in the hands of
the fertilizer makers, but not yet to any great
extent in the hands of the farmers To those
who in school got little insight into chemis.
try it is very easy to understand all the facts
in the case. The chemists have found out
and proved that in all ordinary soils the only
kinds of plant-food likely to be used up by
over-cropping can easily be replaced, and the
land be made as productive as before The
farmers long ago learned that this could be
done by applying the dung Of animals, de-
cayed vegetable and animal matter, ashes,
sosp-suds, muck, and various other things, to
the soil. Later it was found out that vast
piles of bird dung, called 'guano," (Which is
Spanish for 'dung"O was a strong manure.
Still later it was found that bones, when fine.
ly ground were also powerful as a fertilizer.
Later still, rocks were found which are in
composition the same as bones Except the
animal natter, and these when ground, have
proved good for plant-food. And still later
potash has been found in Germany in mex
haustible quantities, buried in the earth. Two
kinds of saltpeter potash saltpeter and soda
saltpeter) have been found to exist in abund.
Ance in the soil of some countries
When the chemists began to study this sub
ject of plant food-that is, of the things
found to be useful in promoting the growth
OF vegetation-they went to work and took
all these substance apart Chat is, they analyz-
ed them, to find what they were made of, for
they were all compounds. They found that
animal dung, which is a complete restorative
of worn soils, contains chiefly three things,
called phosphorus, potassium and nitrogen
The first we have all become familiar with be
cause it is used to top matches. When pure
it is a white, waxy looking substance which
is so inAammable that it has to be kent under
water. When phosphorus burns, there arises
from 1t thick, white smoke. This smoke il
really fine, white powder, and is called
phosphoric acid. Phosphorc acid, If it is
placed in contact with lime, will unite with
~
phate of lime. In fact, it will form three diff
ferent compounds with lime, and the more
lime there is in the compound, the slower il
will dissolve in water. These are the three
kinds about which so much is said in eonnec
ton with fertilizers-'' acid" phosphate con.
tanning but little lime, reverted" phosphate
containing more lime, and "bone" phosphate,
containing still more lime and called bone
phosphate because bones are mostly made of
nfN haon l., = Il
soil, but only more or less soluble
Now for the second fertilizinR material
found in the complete fertilizer dung. This
Is potassium. 1t is a metal looking like sill
yer, but soft as wax, and nearly as inflamma-
BILE as phosphorus. II will burn when il is
thrown upon water. Though a metal, it is
light enough to float, and piece of it thrown
into dish of water will swim around on the
top of it, flaming brilliantly until 1t is all
burnt up. Where did it go to Taste of the
water it was burnt on, and you will find IL has
queer taste. Boil the water down until it is
all evaporated, and when you sugar il of"
you will find that you have got Just exactly
what you get when you boil down lye made
from wood ashes-potash.
The third fertilizing element in dung was
found to be nitrogen. Pure nitrogen is a gas
and in this pure form it constitutes about four
htths Of the air we breath. In this pure form
It Affects but one Of our senses. We can feel
the wind but cannot see, taste or smell IT,
unless it is tainted with something else. But
when nitrogen becomes combined with other
substances 1t becomes puugent enough, and
noticeable by oil our senses. When nitrogen
gas and hydrogen gas unite they form a gas
which is called ammonia (sometimes called
hartshorn) This is always found when dung
cheats" and is one of the oommonest smells
Of dung-heap. When nitrogen combines
with oxygen gas in due proportion, they form
together white liquid that looks as innocent
as water, but is really one Of the strongest
and most corrosive of acids, called nitric acid,
or aqua fortis," Our readers will have no.
ticed that when writing of fertilizers we often
speak of combined nitrogen" BY this con.
venient expression we cover all those oombi-
nations of nitrogen found in dung or other
fertilizers, including ammonia and ita salts
and nitric acid and its salts. ''What are saltsY1
the enquirer will ask. Our common salt used
on food is q salt but there are lots Of other
salts" Some are very familiar, like "Epsom
salts, which is sulphate of magnesia. The
nitrogen salts are quite numerous, and among
those used in fertilizers are the salts Of am
MONA, and the salts of nitric acid. OF tha
first, the sulphate Of ammonia is most com
monty used, and looks almost exactly ike
common salt. The two common nitric acid
salts are the two saltpeters, nitrate Of pot.
ash" Common saltpetor) and nitrate of soda
or soda saltpeter." The latter, being CHEAP.
er, is the one most commonly used in fer.
tilizers
But beside the nitrogen salts" combined
nitrogen is found in other forms equally use.