Introduction

In June 2024 evidence became so overwhelming that I had to do a complete rethink of how the art of meat curing came about. I presented my position and some of the evidence in the Reevaluation of the Discovery of Nitrate and Nitrite Curing. The onus remains to continue a thorough historical evaluation of evidence. Here I present results from a newspaper search I did from the 1600s to the beginning of the 1900s as well as Chemistry Textbooks and other similar historical texts.

This is time-consuming work and I present what I got last night. I will continue to update this as I get time to spend on this.

-> “Urine” from The Hillsborough Recorder, published on August 1, 1844

• Refers to a time in the past when it was highly esteemed. “Urine is one of the most useful, yet neglected, of all substances. It was formerly much more highly esteemed than it is now, but it has fallen into disuse, and very few persons now have any notion of its value.”
• The main benefit by the mid-1800s was seen in agriculture as a fertaliser. “Its neglect is, indeed, much to be regretted, for there is nothing which is more likely to benefit the soil, and at the same time enrich the crops, than this invaluable manure. It is worth ten times more than dung of any kind, as it contains in a very soluble form all the salts and nitrogen which, though voided in a different form, are so necessary to the growth and nourishment of plants. It is easily collected, and if the cisterns are made tight, and covered to prevent evaporation, it may be kept for an indefinite length of time, without losing any of its valuable properties. In villages, it might be collected by a very simple arrangement; and if applied to the land, the inhabitants would soon find the difference in the increased productiveness of their fields.”
• The liquid form is prized over the solid substance of dung which is something I also see in meat curing. The curing agents in liquid form are more valuable to the biological, bacterial and chemical processes than in a solid state. “The solid excrements of animals are useful, but they require a long time to decompose and become fitted for the use of plants. The liquid excrements, on the contrary, are in the best possible state for being taken up by the roots of plants, and hence they produce an immediate effect on the growth of the crops. In towns and villages, where the inhabitants keep their urine and apply it to their gardens, the increased productiveness of their vegetable crops is very remarkable.” Also, “Urine is, therefore, a complete manure, containing all the elements necessary for the growth of plants in a very soluble and available form. It may be applied to the land in its fresh state, but it is generally better to mix it with other substances. If a quantity of gypsum, lime, or ashes is added to the urine, the ammonia which is formed during the decomposition of the urea will be fixed, and prevented from escaping into the air. This mixture forms a very powerful manure, and may be applied with great advantage to all kinds of crops. It is particularly useful for grass, corn, and root crops, and it is also very beneficial to fruit trees and vines.”
• Presidents are mentioned in other cultures who use it extensively. “The Chinese, who are the most successful agriculturists in the world, employ it largely. In Japan, also, it is in universal use; and in many parts of Europe, it is considered so valuable that the inhabitants collect it with great care, and apply it to their fields.”
• By 1844 the basic mechanism behind its value was understood. “In the human body, the urine is secreted by the kidneys, and is composed of water holding in solution various saline and organic matters. The most important of these are urea, uric acid, phosphoric acid, and common salt. The proportion of these different substances varies according to the state of health and the nature of the food; but they are all more or less useful as manure. Urea, which is the principal constituent of urine, is very rich in nitrogen, and is therefore highly valuable as a manure. It is quickly decomposed when exposed to the air, and is then converted into carbonate of ammonia, which is immediately available to plants. Uric acid is also rich in nitrogen, and phosphoric acid is one of the most essential elements for the growth of plants. Common salt is useful in small quantities, but if used in excess, it may be injurious.
• Evaluation of urine vs dung: “The actual amount of ammonia in human urine and cattle dung is about the same; yet in actual practice it is found the effects of urine are nearly double those of dung. Look now for the reason of this; in the first place, the principles which give ammonia in urine runs off by putrefaction into that state. It does nothing else; whereas in dung, the ammonia arises from a slow decay, and the principle which here affords ammonia, and without doubt does, form other products. Hence we have a quick action with the liquid, a slower one with the solid. A second cause of the better effects of the liquid is, that it contains besides its ammonia, a far greater amount of salts, and these give a more permanent effect. The amount of salts in human, cow, and horse dung is about one pound in every hundred. While the urine of the same animals contains nearly six pounds in every hundred. A third cause of the greater fertilizing action is found in the peculiar character of some of these salts, which are composed of soda, potash, lime, etc., united to an acid formed in the animal body. This acid is like the acid of saltpetre; it is a nourisher of plants, as much so as is carbonate acid.”

-> “Urine and Dung” from The Philadelphia Inquirer Sat, Mar 12, 1791

This news article offers possible insight into our evaluation presented in The Hallstatt Curing Method

“Perhaps you do not all know, because you have not tried the means of increasing manure by compost. I have tried it, and wish you to follow my example.

Adjoining the stye where your swine are shut up, which should be dry and warm, fence a yard for them to wallow in; twenty or thirty feet square will be large enough for half a dozen hogs; cover this in the fall or spring with mud, or any rich earth or grass sods; common loam should not be refused, if richer earth cannot be procured. The hogs, having no rings in their noses, will render this mud or earth, if not more than two feet deep, an exceeding rich compost in a year’s time. They will keep it stirring and fermenting with their dung and urine, which will be incorporated with the mud, and thereby their whole strength will be saved; for the mud or earth will prevent the virtues of the dung and urine from being washed into the ground by the heavy rains, or evaporated by the sun and air—it not only saves them, but makes them stronger, by keeping them in a state of constant fermentation—the fermentation will be increased, and the whole mass will be improved by making this yard the receptacle for the weeds of your garden—throw into it your soap suds, brine, and all the greasy slop of the kitchen—you may add potatoe tops, which should be carefully saved for the purpose when you gather the potatoes—the stubborn corn-stalks, which rot slowly in the cow-yard, will soon consume in the hog-yard. Indeed any vegetable or animal substance may be added, for there is none which will not make manure when rotten. Half a dozen hogs, if confined to a stye, and such a yard, will make more than 20 tons of the best manure in one year. The manure should be laid in heaps to mellow with the frosts of one winter, and it will answer to put into the hills of Indian corn as well as horse dung.”

-> “Urine and Dung” from Newcastle upon Tyne, Tyne and Wear, England, dated Tuesday, October 7, 1749

A veterenarian recipe for curing infections in cattle:

“A most excellent and approved Receipt for the Cure of Infection among the Cattle.

GET a Quantity of Urine and of Pigeon’s Dung; to three Pints of Urine put a little strong Beer, and a good Handful of the Dung, and stir it well over a Fire till the Dung be dissolved. A while after it is taken from the Fire, put therein a little Horse Powder, or Diaponte, and a little sweet Butter: If the Beast be costive, add thereto five Eggs, beat in Shells and all, in a Dish by themselves, very small, and mix them with the Drench, being lukewarm. Give a Pint thereof to every Beast, and if need bleed them first in the Neck.”

Ingredients and Preparation

1. Urine and Pigeon’s Dung: The primary ingredients. Urine – believed to have antiseptic properties, and pigeon dung – possibly used for its ammonia content.
2. Strong Beer: Likely used for its fermentation properties and possibly to mask the smell of the other ingredients.
3. Horse Powder or Diaponte: Exact nature of these ingredients unclear. Might refer to powdered herbs or other medicinal substances.
4. Sweet Butter: Added potentially to improve the texture or efficacy of the solution.
5. Eggs with Shells: Beaten and added if the animal is constipated, which suggests an understanding of dietary influences on health.

Method

• The urine and pigeon dung are combined with beer and heated until the dung dissolves.
• After removing from heat, horse powder (or Diaponte) and butter are added.
• If the animal is constipated, beaten eggs with shells are mixed in.
• The mixture is given lukewarm, a pint to each infected animal.
• If necessary, the animal is bled first in the neck.

Possible Interpretation

Urine and dung might have been used for their perceived antiseptic and laxative properties. The addition of eggs for constipation indicates an early understanding of treating digestive issues. Beer, containing alcohol, could have had a slight antiseptic effect, though its primary role may have been to mask unpleasant tastes and smells.

-> Urine and Dung from The Newcastle Weekly Courant, a newspaper from Newcastle upon Tyne, Tyne and Wear, England, dated Tuesday, January 28, 1749

“An infallible Cure to prevent the Infection amongst the Horned Cattle, which may be of the greatest Service to Persons concerned.

TAKE half a Pound of fresh Madder, half a Pound of strong Leaf Tobacco, Pigeon’s Dung, and Rue, each a large Handful; if this cannot be had, a Handful of Devil’s-Bit will serve: These are to be boiled very well in seven Quarts of stale Urine. A drenching Hornful of this to be poured down the Throat of each Beast. The above Quantity will serve 30 Head of Cattle.

Take an Ounce of Asafetida, boiled well in a Pint of Vinegar and a Pint of Urine; a Spoonful of this to be poured into the Nostrils of each Beast.

Take a Pint of Tar, a Pennyworth of Brimstone, mixed together, with three or four Heads of Garlic bruised among it; these to be rubbed on the Nose and Rump of each Beast, which you are to take Care to bleed in both Nostrils. And if any of them take the Disorder after this, you must give them a Quart of Ale, with a Pennyworth of Tobacco infused in it: After that, give them about a Pint of Salad Oil.”

Madder and Tobacco:** Both plants were believed to have medicinal properties. Madder was used for its perceived blood-purifying qualities, and tobacco was often employed for its supposed antiseptic and insecticidal properties.

• Pigeon’s Dung and Urine. Likely used for their ammonia content and potential antiseptic properties.
• Asafetida and Vinegar. Asafetida – a common remedy for digestive and respiratory ailments. Vinegar is an antiseptic.
• Tar, Brimstone, and Garlic. Used for their presumed disinfectant properties. Garlic, in particular, was known for its antimicrobial effects.
• Ale and Tobacco Infusion. Possibly intended to act as a tonic or a stimulant.
• Bleeding. Bleeding was common in historical medicine, based on the belief that it could balance bodily humors and remove “bad blood.

-> Dung and Urine from The Western Flying Post; or, Sherborne and Yeovil Mercury, a newspaper from Sherborne, Dorset, England, dated Thursday, November 13, 1749. 

“The following Mixture has been found to be of Use, as well in Preventing, as in Curing the Distemper, which has so long raged among the Cattle; viz.

For a large full-grown Ox, or Cow, (to be given with a Drenching-Horn) a large Handful, or more, of Hen’s Dung stirred, ’till incorporated, in at least a Quart of hot stale Human Urine; and to be administer’d about Blood warm. To Cattle of a smaller Size, a proportionable Quantity of the like Mixture may be given.”

• Hen’s Dung: Likely used for its ammonia content and potential antiseptic properties.
• Human Urine: Used of hot stale human urine reflects a belief in its antiseptic properties and its role as a solvent to incorporate the dung.

-> Urine from The American Weekly Mercury, a newspaper from Philadelphia, Pennsylvania, dated Sunday, August 28, 1729

“There was lately in an upper County, a Hero of this Class, but he could write; he was famous many Miles for writing with Urine and other sharp Liquids, which was not legible till some Sleights of Hand were used; He was also a Professor of the Mathematicks, and could dextrously describe a Circle tho’ three Points, or Dots, placed in any odd Position, except a tight Line. Moreover, he taught Logick and Latin which few could learn, and those who did could never understand.”

Interpretation: An individual, famous for writing with urine and other sharp (possibly acidic or pungent) liquids. Writing not immediately legible – required some form of trick or sleight of hand to reveal it. This could be interpreted as a form of invisible ink, where the writing only becomes visible under certain conditions, such as exposure to heat or another chemical.

-> Dung from The Western Flying Post; or, Sherborne and Yeovil Mercury, from Sherborne, Dorset, England, dated Monday, February 24, 1766.

“Another very valuable Negro of hers next catched the infection by the smell, and was seized with a most violent fever, and quite delirious; his tongue and head were swelled in a tearful degree; and though the pock appeared the third day, as usual, yet it never rose, and black spots appeared all over him, as if they had been sparks of ink from a brush.

Efficebat etiam per os excrementa imi ventris (Latin for: “It also caused the excretion of faeces through the mouth”). On the sixth day of the pock, still continuing very bad, delirious, and without sleep, since first taken ill, he was given over by the physicians; Mrs. Stewart therefore saw the necessity of giving him something which might make the matter separate from the blood, and give it a turn outwardly, and accordingly composed the following draught, which a grown person may take at once, if they possibly can.

Take half an ounce of Virginian snake root; boil it in two pints of river water for a quarter of an hour. To this decoction add of the best saffron one dram, of fresh goat’s dung two handfuls; infuse these for two hours near the fire; then strain it, and add of lemon juice half an ounce, white sugar as much as will bring it to an agreeable sweetness, French brandy two ounces. Take it warm.”

Interpretation:

• Virginian Snake Root: Virginian Snake Root (Aristolochia serpentaria) – traditional medicinal herb historically used for treating snake bites and other ailments. Believed to have stimulant and diaphoretic properties, aiding in fever reduction and promoting sweating.
• Saffron: Valued for its medicinal properties, including its potential to reduce fever and inflammation.
• Goat’s Dung: Animal dung was used – why is a good question. 🙂
• Lemon Juice: We now know it would provide vitamin C and at the time might have been believed to help purify the blood. They may have had an idea of its general value.
• White Sugar. Probably added to make the mixture palatable.
• French Brandy: Likely as a general stimulant and to provide some antiseptic properties. I would have added 5 L of any brandy around! 🙂 🙂 🙂

-> Urine from The Leeds Intelligencer and Yorkshire General Advertiser*, from Leeds, West Yorkshire, England, dated Tuesday, July 14, 1767

“MEDICAL RECIPES and REMARKS.

A RECIPE for a BRUISE.

WET bran well with stale urine, to which add a little spirits of hartshorn, or crude sal ammoniac in powder; apply it by way of poultice.

Another.

Dissolve some sal ammoniac in a little urine and white wine; dip a rag in it warmed, and apply to the place, renewing it as need be.

Remarks. Of all the salts, there are none more agreeable to the body, and more penetrating, than sal ammoniac (which is chemically extracted out of soot from cattle’s dung) and urine, which contains also a salt similar thereto. This resolves extravasated blood in an admirable manner.”

Interpretation. Here we have two recipes:

Recipe 1: Poultice for a Bruise

1. Ingredients

• Wet bran
• Stale urine
• Spirits of hartshorn (ammonium carbonate)
• Crude sal ammoniac (ammonium chloride) in powder

2. Method

• Wet the bran well with stale urine. The wet bran is the base for the poultice. The Urine – probably for the ammonia – acts as an antiseptic
• Add a little spirits of hartshorn or crude sal ammoniac in powder. Additional ammonia would have helped to reduce swelling and inflammation
• Apply the mixture as a poultice to the bruise.

Recipe 2: Sal Ammoniac Solution

1. Ingredients

• Sal ammoniac
• Urine
• White wine

2. Purpose

• Sal ammoniac (ammonium chloride) – for its ability to dissolve extravasated blood (blood that has leaked out of vessels).
• Urine and white wine – solvents and carriers for the sal ammoniac, enhancing its penetrating ability.

Comments on the use of Sal Ammoniac

The text highlights that sal ammoniac is particularly effective at penetrating the body and dissolving extravasated blood. It notes that sal ammoniac can be chemically extracted from soot produced by burning cattle’s dung, and urine also contains a similar salt. The use of sal ammoniac is praised for its ability to resolve bruises effectively. Ammonium chloride – widely used in various medical and alchemical preparations. Its ability to dissolve blood clots and reduce swelling made it valuable in treating bruises and similar injuries.

Note on Stale Urine Was believed to have antiseptic and therapeutic properties due to its ammonia content.

Spirits of Hartshorn. An interesting substance requiring investigation. From the distillation of deer antlers or ammonium carbonate, commonly used as a smelling salt and in medicinal preparations for its stimulating effects.

Jägermeister comes to mind with its logo featuring a stag with a glowing cross between its antlers. I looked it up and it actually symbolizes the patron saint of hunters, Saint Hubertus. So, sorry, no deer antlers in Jägermeister! 🙂 🙂 Im still going to use the logo as the featured image for this page! 🙂 🙂

-> On Urine from New England Farmer, Page 3, Wednesday, January 3, 1838, Boston, Massachusetts.

(Selected for the New England Farmer.)

LIQUID MANURE.

Urine, although essentially composed of water, yet contains most of the elements of vegetation in a state of solution peculiar to itself, and is combined, through the secretions of vessels, with carbon and saline matter, from which it derives its nutritive properties, as well as with a large portion of ammonia, to which it owes the peculiar smell by which it is distinguished. The various species of urine from different animals, differ in their constituents, and the urine of the same animals alters when any material change is made in the nature of the food.

The analysis by Mr. Brande, of 100 parts of the urine of cows, and by Fourcroy, of horses, the following proportions are found in each, viz:

Cows:

• Phosphate of lime, 3
• Muriate of potash and ammonia, 1.5
• Sulphate of potash, 1.3
• Urea, 6.7
• Uric acid, 0.7
• Free lactic acid, 4.0
• Muriate of soda and ammonia, 4.8
• Water, 84.0

Horses:

• Carbonate of lime, 1.0
• Muriate of potash, 2.5
• Benzoate of soda, 3.0
• Carbonate of lime, 2.1
• Water and mucilage, 91.4

Human urine contains a greater variety of constituents than any other species, and differs in composition, according to the state of the body.

Liquid manure consists of urine with feces, which is gradually collected on subterranean vaults of brick-work, near the stable or hay barn. Those receptacles are generally 40 feet long by 14 wide, and 7 or 8 feet deep; an aperture is left in the side, through which the manure (night soil, from privies) is received from the cart by means of a shoot or trough; and at one end an opening is left to bring it up again, by means of a temporary pump, which delivers it into carts or barrels. Another cistern of double that size, is however, for the most part formed under the range of stables, from each stall of which the urine is conducted to a common grating, through which it is drained into the vault; but in the best regulated, there is a partition in the cistern, with a valve to retain the contents of the first space into the second, to be preserved there free from the later acquisition, and improving materially in its efficacy. This species of manure is indeed relied on beyond any other, upon all the light soils throughout Flanders; and the coarse lands, originally so rich as to preclude the necessity of manure, is now coming into great esteem, being considered as above all other species the most economical; and the benefit is most immediately felt by the application of night soil to the various productions which human sustenance demands, and the appearance of flowers, cucumbers and vegetables.

Experiments on urine have been made on the use of various kinds of soils, to which the manure is applied; and their effects will show how important each is considered in Flanders and its vicinity: nor can there be any doubt, that for many years to come the urine should be more valuable, when properly irrigated, upon all light soils. The expense, probably, and not the advantage, of this highly irrigating manure, has prevented its introduction into some parts of the world. It is indeed used throughout Holland and on all the open flat meadow ground situated on the North Sea; but only sprinkled on soils in China; but, although it is particularly approved by many, by which the number of working animals is so much reduced, that night-soil and urine forms the principal dependence of the farmer. Into a cask or jar is put a collection of putrid animal substances, night-soil, fish, blood, &c., to which is added a certain quantity of urine, but it is never used if not completely filled. A manure, or officer of government then attends, who, upon the vessel being closed, affixes his seal, and in which state it must remain for 6 months at least. When this, or a longer period, has elapsed, the mandarin removes his seal, and grants a certificate as to the quality of the preparation, which is owned by the proprietor, who cries it through the streets as a manure for gardens, and it is sold in quantities as small as an English pint. Before using, it is always diluted with four or five times its bulk of water.

The late Dr. Franklin informed us that he was assured by several Chinese, that human urine, thus prepared, forms a fourth-part of all the manure employed in China, and which is never used until it has reached a high state of putridity. That an article considered of so much importance in that country, should in ours, be so much neglected, is not easy to be accounted for. The quantity which will be preserved in a cistern of middling or moderate size, has been shown, by a series of experiments, to amount to about half a gallon, which, if diluted with double the collection of it, would, according to an intelligent Flemish application, be a sufficient manure for 1-4 of an acre of ground. Urine itself, when diluted with water, forms a highly diluted compound for the best plants; and if the soil is deeply wrought up, to its depth, and inclosed, should then be used to Flax, or Oats, in China. This, it may be observed, that, in hot countries, summer, the pasture where the urine of cattle falls, becomes marked by a rich dark green, when rain falls and the herbage in that quarter continues, the development of ammoniacal salts, arising from the putrefaction of the urine, then occasions it to burn up the grass; yet, on the contrary, an excess of moisture deprives it entirely of effect. Thus, when the whole of the urine of a dwelling-house having been daily thrown on a piece of pasture, during the months of winter, it was found in the following summer to differ but little from the state of that rest of the field,—it having suffered too much by the rain and snow, to arrive at the point of putrefaction. But in the following June, it was again re-jointed in a jar, and covered with a slate, where it remained until it had completely undergone that stage, was then mixed with four times its amount of water, when sprinkled four proper times on the same quantity of pasture, it was found to greatly improve the vegetation.

It is probably no species of manure so generally adopted, and yet so highly valued in Flanders, farm-yards, stables, and by agriculturists of high standing, later, quantities are commonly applied to the barn-yard. We have no means of accurately measuring the urine of animals and the other house-cattle, nor the quantities that arise in the course of a day, for blood, or the expense; but, having been applied in a calculated amount upon a broad level of such, on all clean soils, there is no value such experienced if you feel no common efforts should be paid towards it.

A trial with two-thirds of this water—at about 1 gallon for every 12 lbs,—besides water should be drank. The weight of pure distilled water is 8 lbs. per gallon; if that of urine is heavier, in proportion to the same weight.

Considering, then, the frequent application of water, and the recommendations of government, particularly recommended by the Rev. Mr. Pebbles, who applied it to his land and benefited his pine plant, about 12 years ago, and, since that matter has been highly commended, by some officers who affixed their seal to a given quantity of each cask while less filled, is convinced of the utility by a sewer, and greatly experienced in cattle; this component has received the greatest of proofs, of which it is greatly assisted by a jar, before it is ready for the application to all its careful order, when it shows symptoms of ammoniacal attenuation; and in this way a large quantity of rich manure is raised, equal to about 200 cart-loads, which when applied in small quantities, is equal, if not superior in its effects to its best dung. The expense of filling the jar only amounts to about 38s.

Throughout a great part of Tuscany, the manure of swine is chiefly procured by night-soil and refuse animal matters thrown into it, which in its steeped form by several months in a cistern in the farm-yard, after which the effect of cattle urine is also thrown, and every attention is paid to the management. A species of peculiar import is made from the putrefied water of any kind, in a large jar by Baron Schweigel, in Vienna.

Sweden the urine is collected from barns, stables, and emptied into vats and mixed with clay; these, the ponds, remain for twelve months at least.

In Scotland, some extensive experiments have been made upon the application of liquid manure containing urine; which have proved very favorable. A cistern is constructed under the stables, for carrying the drains to the urine from thirty-five to forty, and sometimes seventy swine. The supply generally amounted to 360 gallons a week, and when land was mixed with three or four times the same quantity of water, irrigating 120 plants, one and three weeks at least have been shown by Sir H. Davy.

In Sweden, the urine is collected from barns and stables, emptied into vats, and mixed with clay; these ponds remain for twelve months at least.

It is then put into vats, from which it is conveyed to the fields, by small conduits, and by others kept for wheat and oats. The expense of a hog-manure, from pigs which are fed on potato diet, and kept in sties, is very small, compared with that from other kinds of manure, because the supply is more regular and extensive. And it has been observed that whenever there is a great deficiency in any part of the farm, it is quickly supplied by liquid manure; which not only saves the necessity of carting dung from distant parts of the farm, but also furnishes an immediate and abundant supply of the richest nutriment to the soil. It is known that the urine of cows and horses contains a great portion of nitrogen; and it has been proved by accurate experiments, that this substance enters largely into the composition of plants, and contributes in a very important degree to their growth and vigour. The same observation applies to the dung of poultry, and of other animals.

In Flanders, the urine of animals is collected with great care, and large quantities of it are applied to the soil with the most satisfactory results. In some districts, it is the only manure used, and it is considered to be of greater value than any other kind of manure. The Flemish farmers have a peculiar method of applying liquid manure, which they consider to be of the greatest importance. They use a large quantity of water with the urine, and apply it in a very diluted state. This is considered to be the best mode of application, as it prevents the burning of the plants, which sometimes occurs when the urine is applied in a concentrated state.

Nothing shows a good farmer better than his attention to the comfort of his family.

-> From The History of Chemistry by Thomas Thomson, published in 1830

1. Avicenna, also known as Ibn Sina, was a Persian polymath who wrote during the late 10th and early 11th centuries, and whose seminal works in medicine and philosophy, particularly “The Canon of Medicine” completed around 1025, profoundly influenced both the Islamic world and Western thought for centuries.

Thompson writes that in the 19th and subsequent chapters of his “Dictions”, “he treats of aurum vivum, of hair, of urine, of eggs, of blood, of glass, of white linen, of horse-dung, and of vinegar.”

The phrase “aurum vivum, of hair, of urine, of eggs, of blood, of glass, of white linen, of horse-dung, and of vinegar” appears to be a list of materials and substances commonly associated with alchemical processes. Aurum Vivum (Living Gold) was a term used in alchemy to refer to a substance believed to possess life-giving or transformative properties, often associated with the philosopher’s stone or the elixir of life.

2. On John Kunkel, Thompson writes, “John Kunkel who acquired a high reputation as a chemist, was born in the Duchy of Sleswick; in the year 1630”. It is of interest to me personally since the town of Tønder where my ancestors came from (also spelt Tonder or Tondern) is located in the southern part of Denmark, which historically was part of the Duchy of Schleswig (Slesvig in Danish, Sleswick in English). They were, however, not chemists but peasants who joined the Dutch East Indian Company and came to the Cape of Good Hope in their service.

Back to the quote from Thomson: “his father was a trading chemist, or apothecary; and Kunkel himself had, in his younger years, paid great attention to the business of an apothecary: he had also diligently studied the different processes of glass-making; and had paid particular attention to the assaying of metals. In the year 1659, he was chamberlain, chemist, and superintendent of apothecaries to the dukes Francis Charles and Julius Henry, of Lauenburg.” For clarification, apothecaries were historical medical professionals who formulated and dispensed medicines to physicians, surgeons, and patients. They were precursors to modern pharmacists and played a crucial role in health care from the Middle Ages through the 19th century. Apothecaries not only prepared and sold medicines but often provided medical advice and treatment. They operated out of apothecary shops, which also sold herbs, spices, and other medical ingredients.

Again, back to Thomson: “While in this situation, he examined many pretended transmutations of metals, and undertook other researches of importance. From this situation he was invited, by John George II., Elector of Saxony, on the recommendation of Dr. Langelott and Counsellor Vogt, as chamberlain and superintendent of the elector’s laboratory, with a considerable salary. From this situation he went to Berlin, where he was chemist to the elector Frederick William; after whose death, his laboratory and glass-house were accidentally burnt. From Berlin he was invited to Stockholm by Charles XI., King of Sweden, who gave him the title of counsellor of metals, and raised him to the rank of a nobleman: here he died, in 1702, in the seventy-second year of his age. Kunkel’s greatest discovery was, the method of extracting phosphorus from urine. This curious substance had been originally discovered by Brandt, a chemist, of Hamburg, in the year 1669, as he was attempting to extract from human urine a liquid capable of converting silver into gold. He showed a specimen of it to Kunkel, with whom he was acquainted: Kunkel mentioned the fact as a piece of news to one Kraft, a friend of his in Dresden, where he then resided: Kraft immediately repaired to Hamburg, and purchased the secret from Brandt for 200 rix-dollars, doubtless exacting from him, at the same time, a promise not to reveal it to any other person. Soon after, he exhibited the phosphorus publicly in Britain and in France; whether for money, or not, does not appear. Kunkel, who had mentioned to his friend his intention of getting possession of the process, being vexed at the treacherous conduct of Kraft, attempted to discover it himself, and, after three or four years labour, he succeeded, though all that he knew from Brandt was, that urine was the substance from which the phosphorus was procured. In consequence of this success, phosphorus was at first distinguished by the epithet of Kunkel added to the name.”

-> Explanation and recap

The text deals with Johann Kunkel’s work in evaluating claims of metal transmutation, a common pursuit in alchemy where the goal was to transform base metals into noble metals like gold. Kunkel, working in a scientific capacity, assessed these claims and conducted other significant chemical experiments.
During the 17th century, alchemy was still widely practised, but it was gradually being supplanted by modern chemistry. Kunkel’s work represents a transition from mystical alchemical practices to empirical scientific research.

Kunkel’s reputation and expertise earned him an invitation to Saxony, where he served as a high-ranking official in the elector’s laboratory, managing chemical research and operations. Saxony, under the rule of John George II., was a hub of scientific inquiry. Kunkel’s role there highlights the importance of chemistry and alchemy in European courts, which often sought practical and financial gains from scientific advancements. Kunkel continued his career in Berlin, serving the elector Frederick William. After the elector’s death, Kunkel’s laboratory was destroyed by fire, a significant setback. The move to Berlin indicates Kunkel’s continued prominence and the trust placed in him by influential leaders. The destruction of his lab was a common risk for early chemists, dealing with volatile substances and rudimentary safety measures.

Kunkel’s expertise was recognized internationally, leading to his appointment in Sweden by King Charles XI. His work there culminated in his ennoblement and recognition as a significant figure in metallurgy and chemistry.

“Kunkel’s greatest discovery was, the method of extracting phosphorus from urine. This curious substance had been originally discovered by Brandt, a chemist, of Hamburg, in the year 1669, as he was attempting to extract from human urine a liquid capable of converting silver into gold.”

Kunkel is credited with refining the method to extract phosphorus from urine, a process initially discovered by Hennig Brandt. Brandt’s goal was alchemical—to create gold—but he accidentally isolated phosphorus, an element with significant scientific importance. Phosphorus was one of the first elements discovered in modern times and played a critical role in advancing chemical knowledge. The discovery marked a departure from alchemical mysticism toward systematic scientific exploration.

Brandt shared his discovery with Kunkel, who in turn informed Kraft. Kraft acquired the secret from Brandt under an agreement of confidentiality. Kraft betrayed Kunkel and frustrated by Kraft’s betrayal, Kunkel embarked on his own efforts to rediscover the process. After several years, he succeeded, leading to the association of his name with phosphorus.

-> The Relevance to Metal Works

It introduces a third chemical element into our consideration of possible value there may have been in introducing animal dung into early metal works. It feeds into our evaluation of the ancient value of dung and urine which sheds light on its use in meat preservation from the perspective that if the ancients were able to desern and exploit the value of nitrogen in metalworks, they would undoubtedly have done so for the far more common practice of meat preservation through curing.

We do this by an analysis of phosphorus, carbon, and nitrogen in dung and urine for metal smelting (1200 BCE to 1600 AD).

Phosphorus in Urine and Dung

Let’s first look at the numbers.

Phosphorus Content in Urine and Dung (Descending Order)

1. Chicken Dung (Dried): ~4-6% phosphorus
2. Goose Dung (Dried): ~3-5% phosphorus
3. Human Feces (Dried): ~1.5-2.5% phosphorus
4. Sheep Dung (Dried): ~1-2% phosphorus
5. Cattle Dung (Dried): ~0.5-1.0% phosphorus
6. Horse Dung (Dried): ~0.5-1.0% phosphorus
7. Human Urine: ~0.1-0.2% phosphorus
8. Animal Urine: ~0.1-0.3% phosphorus

Potential Impact of Phosphorus on Metal Smelting

Late Bronze Age (1200 BCE – 500 BCE)

During the Late Bronze Age, metalsmiths primarily used bronze, an alloy of copper and tin. They likely experimented with various organic materials, including dung, as fuel. The high phosphorus content in dung would not have been understood in chemical terms but might have been noticed for its effects on the final product. Its presence might have slightly altered the hardness of bronze, though the primary metals were tin and copper. The impact of phosphorus would have been minimal in this period due to the dominance of tin and copper in bronze alloys but it would have been noticable.

Early Iron Age (500 BCE – 500 CE)

Iron smelting emerged during this period, and blacksmiths would have continued using organic materials, including dung, for their high carbon content. Phosphorus, even in small amounts, can make iron harder and improve its edge retention. However, it also increases brittleness. The inclusion of phosphorus from dung could have led to the creation of harder but more brittle iron tools and weapons. This effect would have been observed through trial and error, leading to variations in the quality of iron products.

Medieval Period (500 CE – 1500 CE)

As metallurgy advanced, the use of various organic materials, including dung, continued. The unintentional inclusion of phosphorus became more significant as the production methods evolved.

Metallurgists in this time, like their predecessors would have noticed that certain fuels, like dung, produced harder but sometimes more brittle iron and steel. The increased sophistication in metalworking allowed for more consistent results, and the effects of phosphorus would have been more systematically observed, if not fully understood.

Early Modern Period (1500 CE – 1600 AD)

The Early Modern Period saw significant advancements in metallurgical techniques. The deliberate manipulation of material properties became more common, though the understanding of chemical elements remained basic.

The value of Phosphorus would have continued to be exploited from animal dung even if the reason for the effects would not have been understood.

Combined Effect of Carbon, Nitrogen, and Phosphorus in Dung

The other elements of great value in animal dung is carbon and nitrogen.

Carbon:

• Role: Essential in smelting for reducing metal oxides to pure metal.
• Impact: Dung, with its significant carbon content, provided the necessary reducing environment, similar to charcoal, making it a valuable fuel source.

Nitrogen:

• Role: Helps create a reducing atmosphere, preventing oxidation during smelting.
• Impact: High nitrogen content in dung improved smelting efficiency and metal purity, contributing to better quality iron and steel.

Phosphorus:

• Role: Increases hardness and edge retention but can cause brittleness.
• Impact: The presence of phosphorus in dung led to harder iron and steel, beneficial for tools and weapons. However, excessive phosphorus could make the metal brittle, a trade-off that ancient metallurgists would have managed through experience.

Practical Use and Availability

Dung was readily available from domesticated animals and easily dried and concentrated for use in smelting. Its use would have been practical for ancient metallurgists. Dried dung combusts easily, providing necessary heat and reducing gases. This made it more manageable and sustainable than bulkier materials like bones.

Alchemical Perspective

What would the value of animal dung have been from an alchemy perspective? Materials like dung and blood were thought to imbue metal with life force and vitality.

Kunkel’s work in metallurgy and his discoveries, particularly those related to the incorporation of various elements into metalworking, indirectly elucidate the mechanisms by which ancient metallurgists achieved their results using animal dung. Kunkel, known for his contributions to alchemy and early chemistry, helped lay the groundwork for understanding how different elements interact during the smelting process.

The use of dried dung in metal smelting from 1200 BCE to 1600 AD highlights a multifaceted approach to metalworking, where the carbon, nitrogen, and phosphorus content of dung played significant roles. Carbon, as a reducing agent, facilitated the extraction of metal from ores. Nitrogen, while not as prominently discussed in modern metallurgy, contributed to the carburization process, affecting the hardness and brittleness of the final metal product. Phosphorus, although less abundant, had a critical impact on the metallurgical properties of the smelted metal, particularly in terms of hardness and brittleness, which influenced the quality of blades and other metal artefacts.

Kunkel’s exploration into the elemental composition and its effects on metals can be seen as a precursor to understanding why animal dung, with its unique combination of elements, was so effective in ancient metalworking. His work indirectly supports the notion that early metallurgists, through empirical knowledge, harnessed the beneficial properties of dung to achieve desired metallurgical outcomes. This aligns with the historical practices where the practical and alchemical use of dung provided a reliable and multifaceted approach to smelting, resulting in metals with improved characteristics suitable for various applications.

I’m moving away from Kunkel who is the actual subject of this section but I want to list other benefits that the use of dung would have had in the smelting process. Here are a few.

-> As a fuel source. This also relates to its carbon content but it also contains organic materials, such as cellulose, hemicellulose, and lignin, which combust to provide additional heat within the furnace, supporting the high temperatures needed for steel production. Dung is a great fuel source. Its availability, ease of collection, and combustion properties made it an accessible and efficient material to maintain the high temperatures necessary for smelting. This fact can not be overlooked!

-> As binder and flux: Dung could act as a binder and flux. The organic material in dung, when burned, produces ash that can help remove impurities from the metal ore, facilitating the smelting process. This fluxing action helps in lowering the melting point of the ores and assists in separating the metal from the slag.

Dung’s value as a binder and flux in ancient metalworking was multifaceted and highly practical. In comparison to other materials used by ancient metallurgists, such as limestone, silica, and borax, dung offered unique advantages. While limestone and silica were effective fluxes for removing specific impurities, they required processing and did not contribute as fuel sources. Borax, known for its excellent fluxing properties, was expensive and less accessible. Dung’s multifunctionality, combining fluxing, binding, reducing (value of carbon), and fueling properties, made it a superior choice for many ancient metalworkers. Its practicality and effectiveness in smelting processes highlight its significant role in the development of early metallurgy.

Animal dung, particularly from cows, has historically been used as a flux in the steelmaking. One of the primary advantages of using animal dung lies in its composition, which includes both organic and inorganic components. Organic materials, such as cellulose, hemicellulose, and lignin, combust to provide additional heat within the furnace, supporting the high temperatures needed for steel production. This feeds into its value as a fuel source. Simultaneously, the combustion of these organic components leaves behind ash rich in minerals like calcium, potassium, phosphorus, and silica, which are essential fluxing agents.

In the steelmaking process, fluxes play a critical role in purifying molten iron by binding with impurities to form a slag that can be easily removed. The ash from animal dung is particularly effective in this regard. The mineral content in the dung ash combines with impurities such as silica and alumina, lowering their melting points and facilitating the formation of a fluid slag. This slag floats atop the molten iron, allowing impurities to be separated and removed efficiently, resulting in purer steel.

Beyond its functional benefits, using animal dung as a flux is both cost-effective and environmentally friendly. It represents a sustainable use of agricultural waste, providing an inexpensive source of flux material readily available in many rural and agricultural regions.

-> As an insulating material. The ash residue from burnt dung can serve as an insulating material, helping to retain heat within the smelting furnace. This contributes to maintaining the high temperatures required for effective smelting.

-> Aeration and Combustion Control. Dung, when used in combination with other fuels like charcoal or wood, can help in controlling the aeration and combustion process. The structure of dung can allow for a more controlled burn, ensuring a steady temperature during smelting.

-> From the Annals of my European Collaborator

In private communication with my collaborator, she sent me the following valuable information.

“In the Middle Ages, vinegar and ammonia in the form of urine were used as mordants when dying fabrics. To produce indigo, the leaves of the native woad plant were used. These were first crushed in an indigo mill and then left to ferment for two weeks. The fermented material was then moistened with urine and allowed to ferment again. This process was repeated after storing the material for several weeks. The storage took place on air-permeable surfaces. The fermented plants were then mixed with urine and potash at 60 degrees Celsius. After about three days, a dye bath, known as a “küpe,” was formed. Indigo is thus a vat dye. The plant fibres (cotton or linen) or animal fibres (wool and silk) were dipped in this urine vat for an hour. Immediately after dyeing, the fibres were initially yellow but turned blue over time due to oxidation in the air.

The expressions “Blau machen” (literally “to make blue”) and “blauer Montag” (blue Monday) originate from this dyeing process. The dyeing process took a long time back then, so the fabrics were left in the vat over the weekend, and the actual dyeing took place on Monday. This required little physical effort since the blue colour developed on its own through exposure to air. Interestingly, blue dyeing is very common in Burgenland; as you know, iron mining and the goose are unofficial symbols of the region!

The production and processing of dyes followed strict rules set and monitored by the craft guilds. It was often linked with cloth and wool weaving, with blue dyeing playing a significant role. The men and boys in my area wore blue work aprons over their clothes as everyday attire. I believe this practice continued until after World War I. It is certainly described this way in 19th-century literature. In South Tyrol, this tradition still exists! Due to the armistice agreement between Austria-Hungary and Italy on November 3, 1918, and the Treaty of Saint-Germain between the Allied Powers of World War I and the newly created Republic of Austria, South Tyrol was ceded to the Kingdom of Italy in 1919, becoming its northernmost province.”

Evaluation:

I am struck by the key aspect of fermentation technology in antiquity. Fermented meat may have been the earliest form of preservation along with ammonia curing. This is an aspect to delve into.

-> Animal Dung for Thermal Capacity

The structure is almost filled up with sherds of thick-walled ceramic vessels (deep opened bowls with an inverted body) used for the boiling of brine during the Chalcolithic. Their external surface was intentionally roughened, the internal one being well smoothed and often coated with kaolin in order to become less permeable thus protecting the vessel from cracking during the production process. Furthermore, the pots were coated on the outer surface with a mixture of clay and fine straw or animal excrements (probably to increase their thermal capacity). The diameter of the mouths was between 30 cm and 70 cm, and the bottom diameter was between 15 cm and 40 cm. The wall thickness attained up to 2.5 cm. Most vessels were equipped with two pairs of vertically arranged conical knobs each; vessels with one or three knobs are rarely encountered. They were seemingly used to manoeuvre the vessels. (The prehistoric salt-production and urban center of Provadia-Solnitsata, Northeastern Bulgaria and https://journals.openedition.org/mediterranee/8246)