Other substances might be tried as additions, but these were to be the
standard experiments.
Mr. Cholmeley's turnips, grown on a loamy soil had the heaviest crop on
No. 3, the dung, coprolite, and guano, beating the farm-yard manure by
some 5-3/4 tons per acre.
Mr. Johnson's experiments were tried with various manures singly; and
his Peruvian guano gave the greatest weight of the class of substances
tried; but 10 cubic yards of farm-yard manure had previously been
applied to the whole land.
Mr. Maulevere's heaviest weight, also applied singly, was with the 12
tons of dung; but only 14 cwt. more than the dressing with 2 cwt. of
coprolites. This soil was a light clay.
Mr. Newham's on a limestone soil, were the heaviest with No. 3--the
same as Mr. Cholmeley's--and were 16 cwt. heavier than an application of
dung alone.
Mr. Outhwaite's, on a hungry gravel, were the heaviest, with 9-3/4 tons
of dung and 2 cwt. of guano, for all the land had been dunged at this
rate, and exceeded 14-1/2 tons of dung by 2 tons 9 cwt. per acre.
Mr. Scott's were the heaviest on No. 4,--the guano and coprolites, and 1
ton 7 cwt. more than 20 tons of dung,--his soil was a strong loam.
Mr. Wailes's were the heaviest, with 4 cwt. of coprolites, showing an
increase over 20 tons of dung of 2 tons 9 cwt. per acre; the soil is a
useful loam.
The first fact which strikes the observer, is, that as a general rule,
there is not only an addition to the crop by the addition of those
artificial manures, but there is, in some cases, more absolute crop
produced by them than by farm-yard manure alone.
Now to bring this to the test of figures, the coprolites at £5 per ton,
and the guano at £10 per ton, will be at the rate of 2 cwt of each, £1
10s per acre. Now assuming this to be equal to 20 tons of dung per acre,
we should require to be able to produce the dung at 1s 6d per ton to
cost us the same money. But it can be neither produced nor purchased at
any such money. In the whole of the cases referred to, the manure is
most costly, and yet we find hardly any case where there is not an
addition to the crop, of say two to three tons of turnips per acre, by
such an increase of manure as the guano. Now, if a ton of turnips be
worth 10s., or even 9s, there is at once an element of repayment; for,
if a soil be in a condition to give a large crop of turnips, it is
almost certain to be capable of giving a large crop of any other plant
to succeed.
Mr. Charnock gives it as the result of his practical experience, that 4
cwt. of Peruvian guano, without manure, is the cheapest and best mode of
growing turnips; but the general testimony seems to be decidedly in
favor of what all farmers find it the best and easiest to do, viz., to
add a small quantity of artificial manure to that which the farm will
supply, and so to spread the whole over the land, rather than put all
the dung in one place, and all the artificial manure in another.
No one can doubt the true statement of this report, which proves $7 50.
worth of guano equal to 20 tons of manure--reducing the worth of that
to one shilling and sixpence--about 34 cents--per ton, or one dollar a
cord. Now, as manure is often estimated in this country by the cord, and
valued at about $4, and applied at the rate of 6 cords per acre, it
follows that a saving of $14 50 per acre may be made by using 250 lbs.
of guano instead of purchasing the manure. This Yorkshire experiment
exactly corresponds with those made in this country, some of which we
have detailed, and which proves that a farmer cannot buy manure at the
common selling prices; and if he hauls his own the distance of a mile,
he will expend more value of time, than it is worth to him on the land;
because the same value of time--"time is money"--expended for guano,
will bring him better returns. In this, as before stated, we are
confirmed by Professor Mapes; and here is the opinion of Mr. Hovey of
Boston, the eminent horticulturist, which we find in the August No. of
his magazine, as follows--
"If, after such evidence as this, farmers will continue to buy ashes at
eight cents a bushel, or manure at three to six dollars a cord,
including carting, and use them alone, then let them do so, but they
should not complain that their crop cost more than it comes to. To
orchardists and fruit growers, this information is of the greatest
value, and we trust they will not let it pass unheeded."
This opinion is valuable because it has been stoutly asserted, that
however well guano might answer at the South, it was of no use in the
hard soil and cold climate of New England. This is a fallacy which will
soon be cured by knowledge, and self-interest is a very strong prompter
towards the acquisition of the knowledge, that guano is the best,
cheapest, most suitable, convenient and productive manure ever used by a
New England farmer, and just as suitable for that climate and soil as it
is for Virginia. We assert, without fear of successful contradiction,
that there is not a farm--not a field--covered with five-finger vines
and mullens, in the State of Massachusetts, which may not be made to
produce as profitable crops, by the use of guano, as any Connecticut
river farm. Farmers are about the hardest class of men in the world to
learn new doctrines; or that science has anything to do with the
business of this life, and what all other life in a civilized country is
dependent upon. Yet science teaches, by unerring truths, that the plants
the farmer cultivates, are composed of carbon, obtained by plants
chiefly from the soil and atmosphere; oxygen and hydrogen, obtained by
plants chiefly from water, carbonic acid, &c.; nitrogen obtained by
plants chiefly from manure, and also from rain and snow; silicium, in
combination with oxygen, called _silicia_ or sand; lime in combination
with phosphoric and other acids; potash and soda in combination with
acids; magnesia, in combination with acids, and various oxides of
metals, the presence of which, however, is not very important, as they
exist in an exceedingly small quantity. And that guano is composed of
ammonia (formed of nitrogen and hydrogen,) combined with carbonic,
oxalic, phosphoric, and other acids; lime, combined with phosphoric
oxalic, and other acids; potash and soda, combined with muriatic and
sulphuric acids; magnesia, combined with phosphoric and other acids;
animal organic matter, containing carbon, and also nitrogen.
Now, is it not enough to prove that all the ingredients, with the
exception of the metallic oxides, exist in guano, which are required by
the plants grown for the sustenance of man.
Putting guano into the soil, therefore, as a manure, is clearly
restoring to the earth those substances which plants abstract from it,
and which are absolutely necessary for their growth.
The questions, then, which the farmer should now ask are, "which is best
for me to buy, guano or coarse manure?" The evidence just given answers
that question. "I have manure, teams, and men to haul it; my fields are
from one to three miles distant, is it economy for me to let my teams
lay idle and buy guano?" By no means. But you can probably employ men
and teams in other improvements to much better advantage. With your
manure make all your home lots exceedingly rich. With your men and teams
clear off stones, dig ditches to put them into, drain your land, or
build fence--bring bog meadows and swamps into dry cultivation--send
every little brook through artificial channels for irrigation--send
water up from lowland springs and streams by hydraulic rams for the same
purpose, and for stock on the hills; or bring it down from hillsides if
you are so situated; and buy guano for those distant fields, instead of
wasting time in the laborious operation of hauling manure. Those who use
guano, are enabled by the saving of time, to say nothing of their
increased profits, to make improvements which are utterly impossible to
accomplish under the old system.
_How to choose Guano._--As we are satisfied no sensible reader can have
perused the preceding pages, without having come to the determination to
make a trial for himself, we will give him some general instructions
about buying guano.
In the first place, we lay it down as an incontrovertible axiom, that
the Peruvian guano, at the current price for years of that and all
other, is the cheapest and best, because it contains the largest amount
of ammonia, in a perfectly dry state; as a carbonate, true, but because
dry, it is permanent and not likely to loose by volatilization by long
keeping.
If other varieties contain a larger proportion of phosphates, and are
sold at a less price, experience proves they are not cheaper. If an
additional quantity of phosphates is desirable, it can be obtained in a
cheaper form from dissolved bones, or bone dust and shavings of bone
workers; or from mineral phosphates of lime. Recollect, guano under no
other name, has ever equalled the Peruvian, in the results as compared
with the quality or cost.
Therefore buy none but Peruvian. To guard against deception, be careful
of whom you buy. If you cannot buy directly from the agents, be sure the
character of your merchant is a sufficient guarantee against
adulteration.
_To test the quality of Guano._--The best test is the price. Unlike
other merchandise, this article is not subject to fluctuations. Being a
government monopoly, the price at which the agents are to sell here is
fixed in Peru, and that price may be easily known; therefore, if any
dealer offers you Peruvian guano at "a reduced price," you may be sure
the quality is reduced also. Remember, that the lowest price by the ship
load, it can be procured for of the agents in Baltimore or New York is
$46 per ton of 2240 lbs. To this, every fair, honest dealer, must add
freight, insurance and profit. Every man who sells without such
addition, you may be sure will make his profit by short weight or
adulteration.
The next best test is its appearance. Good Peruvian guano is an
impalpable powder, perfectly dry to the touch, of a uniform brownish
yellow color, with a strong smell, like that of spirits of hartshorn,
contained in ammoniacal smelling bottles. But the smell is no test; that
which smells strongest may be worst, as the ammonia may be disengaged by
moisture or by the addition of lime or salt.
_The adulteration of guano_ is carried to a great extent in England, and
probably will be in this country. The principal adulterations are made
by the addition of loam, marl, sand, plaster, old lime, ashes, chalk,
salt, moisture, and by mixture with other guano of a cheaper quality.
The farmer need not depend upon the assertion, "this is a genuine
article--here is the inspector's certificate." We would not give a straw
for a corn basket full of certificates of analysis. The buyer must
analyse for himself. Mr. Nesbit, analytical chemist, London, has just
published a pamphlet from which we have condensed some very plain,
short, simple rules for testing the quality of guano. As the
adulterating substances are generally heavier than the guano, they may
be detected by a comparison of weight and measure. To do this, get a
small glass tube closed at one end, and weigh accurately an ounce of
pure guano, put it in the tube and carefully mark the hight it
fills--try several samples--if there is any difference, mark it. Now
weigh an ounce from a sample adulterated with one fourth its bulk of any
or all the preceding list of articles used for that purpose, and you
will find the difference of bulk between that and the genuine, very
perceptible.
_Test by Burning._--Guano burnt to ashes at a red heat will leave an ash
of a pearly white appearance, not varying in weight from 30 to 35 per
cent. of the quantity burnt. If it is adulterated with marl, sand, clay,
&c., the ash will be about 60 or 65 per cent, of the weight tested, and
be colored with the iron always present in the adulterating substances,
and which is never found in pure guano. This test, to be accurate, must
be done with a nice pair of scales and a platinum cup, which may be
heated over a spirit lamp. Ten grains of the guano are placed in the
platinum cup, which is held by the tongs in the flame of the spirit lamp
for several minutes, until the greater part of the organic matter is
burnt away. It is allowed to cool for a short time, and a few drops of a
strong solution of nitrate of ammonia added, to assist in consuming the
carbon in the residue. The cup is again heated, (taking care to prevent
its boiling over, or losing any of the ash,) until the moisture is quite
evaporated. A full red heat must then be given it, when, if the guano be
pure, the ash will be pearly white, and will not exceed 3-1/2 grains in
weight. If adulterated with sand, marl, &c., the ash will always be
colored, and will weigh more than 3-1/2 grains. Even the simple burning
of a few grains of guano, on a red hot shovel, will often indicate by
the color whether a fraud has been committed; but we cannot particularly
recommend this method, as the iron of the shovel itself will sometimes
give a tinge to the ash. This might be obviated by burning the sample on
a common earthen plate.
If the adulteration of guano has been made by sand, it can be detected
by dissolving the ashes in muriatic acid. The sand will remain--if it is
more than one per cent., it has probably been added fraudulently. As
iron exists in loam, it will show in the color of the ash if that is the
substance used for adulteration. If lime has been added, it can be
detected by dissolving the ash in muriatic acid and separating the sand,
loam and iron, if present, by filtration, and then adding oxalate of
ammonia to the liquid. If it shows more than a mere trace of lime, it
has been falsified.
_Test by salt._--Saturate a quart of water and strain it; pour some in a
saucer and sprinkle guano upon the surface. Good guano sinks
immediately, leaving only a slight scum. If it has been adulterated by
any light or flocculent matters, they will be seen upon the surface of
the brine.
_Test by Acid._--Put a teaspoonful of guano in a wine glass and add a
little vinegar or dilute muriatic acid. If ground limestone or chalk
have been added, the effervessence will show it. A genuine article will
only show a few bubbles.
_Test by Water._--The following simple plan will easily detect all the
ordinary adulterations of guano. Procure a wide mouthed bottle, with
solid glass stopper; fill with water and insert the stopper; let the
exterior be well dried. In one pan of accurate scales, place the
bottle; counterpoise by shot, sand or gravel. Pour out two thirds of
the water, and put in four ounces avoirdupois of guano. Agitate the
bottle, add more water; let it rest a couple of minutes, and fill with
water, so the froth all escapes; insert the stopper, wipe dry, and
replace the bottle in the scale. Add now to the counterpoised scale, one
and a half ounces avoirdupois, and a fourpenny piece; if the bottle
prove the heavier, the guano is, in all probability, adulterated. Add in
addition a three-penny piece, and if the bottle is still heaviest the
guano is undoubtedly adulterated. By this simple experiment, a very
small amount of sand, marl, &c., is detected.
If farmers will not use some of these simple tests, or employ a chemist
to detect suspected adulteration; or if they will buy guano of men who
have no character to lose, and who offer to sell below a price to afford
them a living profit, they cannot be pitied if they are cheated.
_Prepared Guano._--Never buy anything bearing that name, unless you wish
to verify the adage of "the fool and his money are soon parted."
_Analysis of Prepared Guano._--We give an analysis of one sample of
domestic manufacture, and two British. No. 1. was offered in London and
actually sold as Peruvian guano, to farmers in the south of England;
just because they were so neglectful of their own interests as not to
inform themselves that an article sold for $35 a ton, could not be
genuine, while the regular government price remained fixed at $47. It
may readily be seen by the analysis, how they were cheated into paying
that price for an article of which 74 per cent. is plaster, and only
half of one per cent. ammonia.