The Marietta journal. [volume] (Marietta, Ga.) 1866-1909, 1902-12-18
SEVENTH LETTER ON AGRlCuL.
TURAL CHEMISTRY.
Continuing the Letters Of State Chem.
list to Georgia Farmers on AgrIcuI-
tureaI hemstry-Descriptlo of
Fertilizer Materials

Continued.
Cotton seed meal blood, tankage,
ETC., which | have described to you
In the last letter. are known as or
ganic" sources OF ammonia, or rather
| of nitrogen. Habit is so strong, you
see, 1t Is hard to get rid of the use
] OF that word ammonia. Nitrogen is
| much the better term for our use. Be-
sides the organic sources of nitrogen
! we also have what are known as the
inorganic sources. have explained
in previous letter fully the meaning
OF these two terms, but lest you may
have forgotten, will stop a moment
to say that an organic substance may
| be either vegetable or animal, thus a
leaf, a seed, piece OF meat or OF skin
| are organic substances. An inorganic
! substance is the opposite of these,
! and Is mineral In its nature, a piece
of rock or OF iron is inorganic. The
chief inorganic source of nitrogen,
then, Is nitrate of soda, also commonly
called Chill Saltpetre;" saltpetre be-
cause 1t has many Of the properties of
real saltpetre, which is nitrate of pot
ash and Chill because IL is imported
| from Chill In South America.
Nitrate OF potash or true saltpetre
is very valuable fertiHzing compound,
yielding both nitrogen and potash to
the plant, but 1t Is much too expensive
TO buy In this FORM 1t is, therefore,
better. or, rather, cheaper to buy nj
trate OF soda and muriate of potash
separately, and then mix them to-
gether. when we will accomplish rac-
tically the same results from a fertil-
izing standpoint, and for a smaller out
lay Of money, than II we bought the
same elements in form Of nitrate Of
potash. Nitrate OF soda IL such an
important salt for fertilizer purposes
that I will go into some Titled etail
| about It.
The entire supply at present comes
from the western coast of Chill. II ex.
tends in q narrow strip OF land run
ming north and south for about 26O
miles, at an average distance of about
IA miles from the ocean The country
where 1t is found Is a desert, It never
rains there and the whole region IL
bare Of vegetation and destitute Of
water. The nitrate rock is call ga
liche" pronounced Calee-chay) and
the best quality has the following com
position:
Sodium nitrate, 50 per cent sodium
chloride &c per cent, sodium suiphate
per cent, magnesium sulphate 3 per
cent, insoluble matter IA per cent, So
dunn iodate, sodium nitrite, magnesi.
um chloride, magnesium nitrate, potas
SUM chloride ] per cent making the
whole.
The average quality Of "caIiche" con
ta.ns from 30 to 40 per cen Of sodium
nitrate, and the poorest quality worked
ranges from II to 80 per cent sodium
nitrate. The "caliche" occurs from 6
to 10 feet below the surface of the
ground and the vein or stratum va.
ries from a foot and half to twelve
feet in thickness.
The process of extracting and sepa-
rating the valuable nitrate of soda
from the rest ow the "caliche" Is done
by means Of water in which the nj
trs,te Of soda disolves, and from which
II is crystallized. A description of
the process would be tedious. Suf-
fee It to say that costly plant is re-
quired for the purpose, and that the
work is so we'll done that the product
when finished contains about 95 per
cent nitrate Of soda which is equiva-
lent TO 1865 per cent Of nitrogen, or