56 
AMERICAN AGRICULTURIST. 
^mmrait Agriculturist. 
.Mew-Yoiv, Y/ednesaay, April 5, 1854. 
SUPER-PHOSPHATE OF LIME. 
DIFFERENT KINDS IN THE MARKET—HOW MADE— 
THE BEST KIND TO BUY, AC. 
In answer to frequent inquiries, we will give 
a few general statements on this subject. 
Super-phosphate of lime, as most are pro¬ 
bably aware, is made by dissolving phosphate 
of lime in sulphuric acid (oil of vitriol.) 
There are three methods of making this: 
1st. Dissolving unburned bones, ground or 
unground. 
2d. Di.-solving burned bones. 
3d. Dissolving a native mineral phosphate of 
lime, called apatite. 
Since unburned bones contain considerable 
animal matter, the super-phosphate made from 
these is the most valuable fertilizer, unless for 
land already abounding in organic matter. 
The second kind, from burned bones, is gen¬ 
erally better than the third, because the mineral 
phosphate usually contains more or less of for¬ 
eign substances. 
A greater portion, if not all, of the super-phos¬ 
phate sold in the market, is made from burned 
bones. The manufacturers do not prepare 
bones for this purpose, but procure them ready 
burned from the sugar houses, where they have 
been used for refining sugar. The sugar re¬ 
finers burn the bones away from the air, so as 
to preserve the animal charcoal formed from 
the organic part, and grind them to a powder. 
The sugar syrups are passed through this sub¬ 
stance to purify them. After the substance 
thus prepared, (called bone-black or bone-earth,) 
has been used awhile, it is again burned, and 
again used. Sometimes it is re-burned and used 
four or five times, and then thrown out into a 
heap, or placed in the empty sugar hogsheads, 
and sold for a small sum to the super-phosphate 
manufactories. 
B 
At these factories the bone-earth is mixed 
intimately with a portion of sulphuric acid, 
(oil of vitriol,) which changes the phosphate of 
lime in the bones (which has not been altered 
by the burning) into super-phosphate of lime. 
Sometimes the bone earth and acid are mixed 
by putting them in a cask and stirring or sho¬ 
velling them well together. Others do the mix¬ 
ing with machinery. This last method is pre¬ 
ferable, since the mixing is more thorough and 
uniform. The heat produced by the action of 
the acid upon the bone, is sufficient to expel 
the water and leave the mass dry. This sub¬ 
stance, thus simply made, is the commercial su¬ 
per-phosphate of lime. It is of a dark color, al¬ 
most like powdered charcoal. 
Several manufacturers claim to improve this 
by mixing other substances with it, such as 
guano, sulphate of ammonia, &c. The addition 
of ammonia in some form is doubtless an im¬ 
provement for grain and grass crops, and on 
poor lands, for root crops, though on most soils, 
if not all, we should prefer to buy the-simple 
super phosphate, and add manure from the 
farm-yard or the compost heap. But a word 
about these extra substances added by the man¬ 
ufacturers. 
Some claim to add sulphate of ammonia. Now 
this article is expensive, and we think we are 
entirely safe in saying that five tons of sulphate 
of ammonia have never been purchased in this 
country, by all the manufacturers of super-phos¬ 
phate of lime put together. 
Others claim to supply ammonia from the gas 
works. In some recent inquiries, instituted for 
the purpose of ascertaining whether there were 
around the gas works of the city any materials 
that might be profitably used by our farmers as 
fertilizers, we could not learn that any of the 
ammoniacal liquors were saved by any person. 
We have been informed that in an adjoining 
city (Williamsburgh) there is a manufactory of 
sulphate of ammonia, but this probably does 
not at best supply more than enough for one 
manufacturer of super-phosphate. If there are 
other sources of the ammonia claimed to be 
used for this purpose, we shall be glad to be in¬ 
formed of, and chronicle the fact. There is, then, 
we believe, but one further source from which 
ammonia is obtained to add to the super-phos¬ 
phate, and that is guano. 
Several manufacturers do add more or less 
guano. This gives to the super-phosphate a 
lighter color and a peculiar odor. We shall be 
glad to know of a certainty, that no other sub¬ 
stances, such as yellow earth, &c., is added to 
change the color and cheapen the manufacture. 
As far as guano is added, the article is certainly 
not made worse; for at the same price per ton 
we prefer guano to super-phosphate for all crops, 
except perhaps the root crops and old grass 
lands. As we have before stated, for some crops 
a mixture of guano and super-phosphate is 
doubtless better than either alone. But as we 
said in a former number, we advise farmers to 
buy the guano and super-phosphate separately , 
and make the mixture themselves, by thoroughly 
mixing the two together upon a floor. 
What we recommend then is, that manufac¬ 
turers should confine themselves to putting up 
the simple super-phosphate. This we advise 
farmers to buy for their old grass lands, for 
root crops especially, and in small quantities for 
experiment upon other crops, and upon gardens, 
trees, &c. 
Notwithstanding all that has been written on 
this subject, we consider it yet an unsettled 
question, whether an indiscriminate use of su¬ 
per-phosphate of lime on other crops than tur¬ 
nips is profitable. We advise every farmer to 
try it carefully as an experiment. It can seldom 
do harm, it will generally do some good. Will 
it pay ? We have heard of several instances 
where it has paid, but as a Connecticut corres¬ 
pondent justly remarked in our last number, 
“ nobody is interested to chronicle the failures.” 
Fellow-farmers let us have both sides of the 
question. We do not want puffs or condemna¬ 
tions of this or that man’s manufacture. Hon¬ 
estly made, super-phosphate is essentially the 
same thing, no matter by whom manufactured. 
We put no confidence in this or that professed 
addition of other materials. We want to know 
the effect of super-phosphate of lime alone. 
If any one makes the article from unburned 
bones, let him frankly and openly so advertise 
it. If he adds other substances let him as 
frankly and openly state what and how much 
he adds, and allow farmers to see his daily pro¬ 
cess; and we advise him to tear down all suspi¬ 
cious “ no admittance" signs from over the door 
of his factory. We are no friend to secret 
medicines for a sick body, or for sick land. If 
the physician offers us a secret pill we eschew 
it, and so we treat secret manures, of whatever 
kind. 
What we are Doing. —We think our readers • 
capable of appreciating a good paper, and we do 
not deem it necessary to imitate some of our 
cotemporaries—in telling them from week to 
week how much we are doing. It is agreeable, 
however, to know that our labors are valued, 
and it is with no little pleasure that we daily 
meet such expressions as those contained in the 
following extract from a letter, sent us by an old 
farmer, to whom we are indebted for several sub¬ 
scribers : 
“ * * * * I have just received and 
read your Agriculturist of March 29; and allow 
me to say that I think you are not only going 
ahead of all other agricultural papers, (of which 
I take the best six,) but you are even excelling 
yourselves. In the number before me, I find 
some thirty-five columns of instructive, common- 
sense agricultural matter, almost all of which I 
see was written for your paper—I mean our pa¬ 
per—by its editors and correspondents. * * * 
I like to show my neighbors such a paper as you 
weekly send me, and let them see what a treat 
they can have for less than four cents a week. 
Please send me two or three extra copies as spe¬ 
cimens.” * * * 
-—->* ♦- 
GUANO-HOW TO APPLY TO CORN. 
A “Farmer,” in Windham Co. (Ct.) Tele¬ 
graph, thinks us wrong in our objections to put¬ 
ting guano into the hill with seed corn. He 
says, “cover it two inches with soil, and drop 
on the seed, and he will warrant not more than 
one kernel in a hundred will fail to come up.” 
With two inches of soil over the guano, the 
corn may “come up,” but he may be pretty 
sure it will not “ grow up” very high or thrifty. 
Every little root that penetrates to the guano 
will be destroyed. There may be side roots 
enough to keep the corn alive and support a 
partial growth. Guano is so caustic in its na¬ 
ture, that it needs to be incorporated with the 
soil thoroughly before it comes in contact with 
the roots. If applied at planting or hoeing, it 
should be placed at least four inches distance 
from the stalks in the hill, so that the corn will 
only receive the dilute washings of the guano. 
We repeat, that experience has shown, the 
best course generally speaking to be, mixing the 
guano thoroughly with the whole soil, some 
time before sowing or planting. It will remain 
in the soil; the first roots will find but little of 
it, not enough to destroy them, but enough to 
supply their present demands; and as the roots 
extend farther and deeper, they will continually 
find new portions to supply the successive 
wants of the stalk and grain. 
Who keeps Fowls for Sale ?—Since t'he re¬ 
cent Poultry Shows, we have had, and are con¬ 
stantly receiving, numerous inquiries for all 
sorts of fowls. We cannot privately answer all 
such letters, and we suggest that to meet these 
wants, it will be for the interest of breeders of 
fowls and other animals, to advertise and par¬ 
ticularly describe what they have to sell, giving 
the price, how they can be forwarded, and also 
stating the purity of the breed, &c. This course 
will bring breeders and purchasers into direct 
