Part 7 (1/2)
The questions, then, which the farmer should now ask are, ”which is best for me to buy, guano or coa.r.s.e 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 quant.i.ty 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 s.h.i.+p 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 princ.i.p.al 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 a.s.sertion, ”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 a.n.a.lysis. The buyer must a.n.a.lyse for himself. Mr. Nesbit, a.n.a.lytical 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 gla.s.s 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 quant.i.ty 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 a.s.sist 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 sc.u.m. 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 gla.s.s 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 gla.s.s 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.”
_a.n.a.lysis of Prepared Guano._--We give an a.n.a.lysis 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 a.n.a.lysis, 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.
No. 1. Gypsum, 74.05
Phosphate of lime, 14.05
Sand, 2.64
Moisture and loss, 9.26 ------ 100.00 ------ Ammonia, 0.51
The other sample is still worse. This was sold as Saldana Bay guano, at $15 to $20 a ton. It was composed of
Sand, 48.81
Phosphate of lime, 10.21
Gypsum, 5.81
Chalk, 22.73
Moisture, 12.44 ------ 100.00 ------ Ammonia, a trace