The Laurens advertiser. (Laurens, S.C.) 1885-1973, 1885-09-23

phosphate 0f litne IL Is ,BbsofbBd by
plants and assists powerfully In their
Development and fruiting; it then
passes into the structures of man and
animals. Anhydrous phosphoric acid
contains 81 of PHOSPHORUS and 40 of
oxygen, total n. In nature an equiv
alent of pbosphoric acid is alw avs
combined with three equivalents. of
lime. In this state phosphate of lime
is insoluble and no value to n crop
except in certain acid soils, newly
cleVrcd, where reaction may render it
soluble. 1t must be powdered very
fine and carefully mixed with the soil.
Natural phosphates are made soluble
by being treated with %sulphuric acid
weakened with water. Then two
equivalents of lime are converted into
sulphatc of lime and replaced in the
phosphate by two equivalents of water.
Thus the phosphoric acid is now COM
bincd with but equivalent of lime
and water; in this form it is soluble.
This is the method of procedure:
the mineral phosphate of lime or tri-
calcique is ground fine and passed
through a sieve. Fifty 10 eighty per
cent. of its weight in subpluric acid at
SO degrees is poured upon it. Tho
mixture is well worked and the rcac-
ton takes place. The %sulphuric acid
attacks the tricalciquc phosphate, takes
up two equivalents of lime to form a
combination with the phoSphoric acid.
placed for the acid by two equivalents
of water borrowed from the hydrated
sulphuric acid. We thus obtain a
product that is an equivalent OF mono
calcique phosphate containing two
equivalents of water and some sui
phate Of lime.
There are besides in this product
certain earthly matters and metallic
oXydes which mineral phosphates
always contain in more or less Quanti-
ties. This is the impure mono-calcique
phosphate Or supcrphosphatc of lime
of commerce in which tho phOsphoric
acid is immediately soluble in water,
or at least in the alkaline citrate OF
ammonia which is generally used in
the making of chemical fertilizers. Its
richness in soluble phosphoric acid
varies from twelve to fifteen per cent,
according to the composition of the
natural phosphate used in making il.
The supcrphosphate contains an
average of sixty per cent. of anhy-
drous sulphatc of lime or plaster,
which is formed during the reaction.
Reverted phosphatcs arc those which,
soluble In water at the time of the
| preparation of the superphosphatc,
cease to be at the end of u certain time
from the combination of part of tho
phosphoric acid with the pcroXyde OF
of iron and aluminium which the natu-
raj phosphates always contain. 1t is
worth no more than the precipitatcd OF
bicalciquc phosphate, for the reverted
phosphate is only soluble after remain
ing a long time in an acid soil.
To find how much phosphoric acid
there is in a tricalciquc phosphate,
divide by 2.1S, and to know how mucl
tricalcique phosphate TO the quantity
of phosphoric acid found, multiply by
2.18. For example,: If a supcrphos
plate contains fifteen per cent. of sol
ublc phosphoric acid, multiply this
fifteen by 2.18 and we find 1910 pei
cent. of tribasic phosphate contained
in the superphosphate.
For many years bones were the only
practicable source of phosphate o.
lime. They were gotten at first from
bone pits made by refuse animals an(
even went SO far as to rifle old graves
Eli Beaumont, Professor of Geolog,
at the school of mSles, begged Mr.
Joseph Lamballe, the celebrated sur
gcon, to weigh a good many differcn
skeletons and found that n dry human
skeleton weighed an average of hin,
pounds and contained six pounds o
phosphate of lime. From these figure
it was concluded that from tie time 0
the Gauls to the present day our methot
of burying the dead had covered in tn
French soil an immense mass of phos
phorous evual to forty-five millions o
pounds of phosphate of lime.
But we need not be uneasy and ma,
continue to respect u dead. A few
years working of the numerous de
posts of natural phosphatcs now i,
France will compensate this loss
Farmers will be several thousand year.
e~xhausting the deposits already fount
and others are continually being found
Forty departments in France have de
posts Oh phosphate of lime Now work
ed. Phosphoric- acid is found on al
cultivated continents and III immcasur
able quantities.
The phosphate Of bones is, Xix,
manure, but an imperfect fertilizer
The mineral p~hosphstc alone rcall,
enriches the soil. Bones are now onl,
used in preparing a m~ono-calciqu,
phosphate to obtain industrial phos
phorous. Agriculture really relies OF
geological phosphates