Vermont watchman and State journal. [volume] (Montpelier, Vt.) 1836-1883, 1882-03-01
Homemade and Other superphosphates.
Mr.. John G. Thompson writes to us fror
Washington, as follows:

home-mhue anu Uther SuperpnOsphates.
Mr.. John G. Thompson writes TO us from
Washington, as follows
=" recently attended a lecture on agriculture
by DIR. Cutting of Lunenburgh In which he stated
that one barrel Of bone-meal and three gallons Of
suphuric acid mixed together (he told his hearers,
at some length, how TO mix it) was equal to any
ton OF commercial fertilizer that could be bought.
What would you advise any one to do about try
ing it?'
Public speakers sometimes get badly mis-
understood. We know that by experience.
Even writing, plain and fair before the eyes,
is often sadly misconstrued by hasty
reader, aud Of course speaking is much more
liable TO the same occurrence. We say this
because we can hardly believe that 80 care
full and accurate man as Dr. Cutting could
have said, without qualification, what Mr..
Thompson reports.
Here are the facts. A good honest, am
moniated bone superphosphate should be
(and by honest manufacturers is supposed
to be) made just in the way described by
DIR. Cutting. A barrel of bone meal weighs
about 2l0 pounds. Three gallons of sui
phuric acid weighs less than fifty pounds.
This must be diluted with an equal bulk of
water, weighing twenty-four pounds. As
strong heat is developed by the mixture,
much OF the water evaporates therefore the
superphosphate so made from a barrel of
bone dust would not weigh much if any
over 275 pounds. The question naturally
arises, how can 275 be equal to 2,000P Was
Dr. Cutting misunderstood, or does he
charge fertilizer manufacturers, without ex-
ception, with committing such enormous
frauds as must be committed in making a
ton of superphosphate out of barrel of
bone dust We have stood by and seen the
hands making superphosphate at the Brad
ley works. The material used was not Or
dinary ground bone, but ground bone char
coal, "animsl charcoal" as it is called.
This is made in the Bradley works by char
ring the bones in iron retorts. When made
it is carefully ground aud granulated, and
sold to the sugar refners, who use it in
making filters through which syrup made Of
brown sugar is passed to take out the color
and impurity before boiling it down to make
white sugar. These filters soon become
clogged, and the bone charcoal has to be
reheated before it will again act as puri-
fer of syrup. This is done several times,
and then, being no longer useful for that
purpose, 1t is resold to the Bradley COM
pany, who use it for making fertilizers.
Only part of the bones are used for this
purpose, the thin or very soft bones not be-
ing suited to sugar refining. These latter
are steamed to extract the grease aud then
ground, to be directly used for fertilizers OF
sold as bonedust. Those who have used
the Bradley phosphate as sold in New Eng
laud know that it is black, and smells pretty
strong. 1t is black because made from bone
char, and the smell is due to the rank am
moniacal liquor extracted from the bones
and ION account of its fertilzing value,
mixed with them again when made into su
perphosphate. 1t is claimed, and we believe
truly, that bone char is worth as much al
raw bone-dust for making fertilizers when
the ammoniacal liquor extracted from it i:
mixed with it in the manufacture. The
fact that it can be first used for sugar re
fning and then becomes waste product,
returned at low cost to the makers for use
as fertilizer, reduces its cost, and ought
at least, to make the superphosphate COM
cheaper to the farmers.
Besides bone char aud bone dust, fertili
ger manufacturers use bone-ash, brought BY
the ship load from South America, being
the burnt bones of cattle slaughtered there
The quantity of this, however, is compare
lively small, but if used alone, it makes 9
very concentrated and powerful superphos
phate. The South Carolina phosphate rock
and other phosphate minerals, are also used
and, if of good quality, they make as gooc
a superphosphate as bones. Most super
phosphates sold in New England have am
monia in some form added to them. Raw
bone phosphate is naturally ammoniated
the animal matter of the bones furnishing
ammonia. Bone char phosphate is ammo
mated by the return of the ammoniaca
liquor extracted in charring, as above de
scribed. Ammoniated mineral phosphate
receive their ammonia by the addition o
sulphate Of ammonia, or of some anima
matter, such as the fish pomace from tn
porgy oil factories or the dried blood an,
meat scraps from the great slaughter house
called abbatoirs." All of these ammonia,
ing materials add to the cost of fertilizer
and reduce the proportional amount of pho'
phoric acid,-that is, if you have a super
phosphate made of ground bone and acit
and to increase the ammonia you add an
substance containing it, of course this re
duces the percentage of phosphoric aci,
Just in proportion TO the bulk of ammon
acal material added. Tue more bulky sue
material is, in proportion to the ammoni
in it, the more it dilutes the superphosphat,
and in this way some of the ammoniate
superphosphates in the market are mad
much inferior to pure raw bone supe
phosphate which has had its ammoni
brought up TO standard by the addition o
concentrated ammoniacal substance.
the Bradley method it is claimed tina
though the ammoniacal liquor is not yer
concentrated, yet, as an equal bulk of watt
must always be added to commercial su
phuric acid before it will combine with tn
bone the water of this liquor serves thi
purpose, with the practical result Of concel
trating the ammonia This is Just pie
when full strength acid is used.
Our readers will see that there is consi
cradle chance for variation in the value
phosphate fertilizers, especially when an
moniated, according TO the way they al
manufactured. But most of the leadin
} makers sell by analysis, and guarantee oe
, tain percentages of phosphoric acid, solub
and insoluble, and of ammonia. Some
! these fertilizers might be made good de
better than they are, but few If any Of the
are 80 greatly reduced rs one would be Il
to believe by the statement, as reported, I
DR.. Cutting. We should be glad to he
what the doctor has to say about it.
THAT little mutual admiration coter
known as the New England Agricultur
8 Society held its annual meeting the 9th
, day, and
NH