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Some comments on Chaucer's Yeomans tale
by:
Guthrie Stuart
Many people will have heard of Chaucers masterpiece “The Canterbury tales” but few will have read it in the original early English. Within it there is one story that is directly relevant to study of Medieval Alchemy, because it mentions a great many materials and much of the equipment then in use by alchemists.
The story, as such, is that a Canon, a religious man who has taken some form of holy orders, joins the party on its way to Canterbury, accompanied by his servant. I am not completely sure about the motive, but the impression I get is that the Canon’s servant then proceeded to deliberately tell the party that his master is very rich and can multiply gold, and the Canon, on hearing this, tells the yeoman to hold his tongue.
The yeoman ignores this injunction, and so the Canon leaves before anyone starts asking questions about the accusations. The yeoman then proceeds to slag off the Canon and tell a long tale about the work he was engaged in and how he swindled people. But the aim in this short article is to list the alchemically related matters and explain a little about them.
For us re-enactors, having some evidence from the period, even if it more written for entertainment than information, is still very useful. And the tale has such details as suggest Chaucer was well studied and knowledgeable about what was at that time a topic for learned churchmen. By investigating the materials and equipment used, I can then source replicas and gather substances to demonstrate the learning of the period to members of the public.
A list of substances mentioned in the tale:
- Orpiment
- burnt bones
- iron scale
- Salt
- pepper (“pepper dear”, presumably meaning expensive and hard to get)
- glass
- quicksilver
- porphyry (a hard close grained stone for grinding material)
- litharge
- Armenian bole
- borax
- the green of brass
- dark bulls gall
- Arsenic
- sal Ammoniac
- brimstone
- unslaked lime
- chalk
- white of egg
- ashes
- dung
- urine
- clay
- oil of tartar
- alum
- yeast
- wort
- artoll
- realgar
- Silver
- Gold
- Magnesia
Most readers of the period would recognise some of these substances, but not all are so readily come by. It would have been necessary to purchase many of them, and of course gold and silver would be rather expensive. A number of the substances are very rare, such as Orpiment and Realgar, and Armenian bole was originally found in Armenia, which was rather a long way away at that time. Dangerous chemicals such as Orpiment and Realgar are mentioned in Agricolas 16th century work as Arsenical Sulphides, although I am not so sure precisely what the names stood for in the 14th century.
There is however plenty of evidence from earlier alchemical works to suggest that they were indeed colouring metals with these minerals for over a thousand years. These would have had to be imported, as would pepper, borax, and others. Dung, clay, and clay mixed with horses or men’s hair would have been used as lute to keep the vessels airtight.
Interestingly, Magnesia is mentioned in other Alchemical texts as being very important for making the stone, but it is not always clear what magnesia was at that time. Reed in “”Through Alchemy to Chemistry” suggests it might have been a quicksilver based material, but nowadays of course it is more related to the element magnesium, which was isolated in 1808 by Humphrey Davy. There is no evidence that I can find that at the time they were using magnesium bearing minerals in alchemy.
Interestingly I can find no mention of Marcasite, which is used by Thomas Norton, (one of the most famous English Alchemists) nearly a century later and was a term already known of in Alchemy from Geber and others. So further study may elicit some specific authorities which Chaucer was more familiar with than others.
Activities mentioned:
- sublimating
- calcining
- amalgamating
- grinding
- distillation
- albication
- cementation
- fermentation
I am not sure what Albication is, but according to the internet it is the process of becoming white, or developing white patches. This would be accomplished using Arsenical compounds such as realgar and Orpiment, or indeed Arsenic itself, although I believe that name was used more for the Oxide than the pure element. White metals can of course mimic Silver to fool the unsophisticated.
Cementation is a process whereby impure gold is placed in a crucible or sealed box with salt or vitriol and ground tiles or bricks and heated, such that the gold is kept hot, but not so hot it melts. This is kept up for many hours, during which time impurities in the gold, such as lead or silver, will be turned into chlorides and absorbed by the bricks or tiles. It was definitely recommended in the Latin Geber for purification of the metals to be used in the great work. I do not know how long it has been around as a process, but it may well date back to the ancient Egyptians.
Sublimation means heating a substance until it vaporises then condensing it, often done in an enclosed vessel on a pure substance such as sulphur, or else to separate it from impurities, whereas distillation is used at this time to create powerful waters such as the mineral acids.
Fermentation of course refers to a process such as the production of wine or beer, but in an alchemical sense applies to the production of a new material from the old, often with a change in colour.
Amalgamation means joining together, and an amalgam is made by gently heating gold and mercury, such that the mercury dissolves the gold. It is an action often undertaken in Alchemy at some point in the process, although exactly when and how is often cloaked in special language.
The story also mentioned a “chalk-stone”, used for casting silver and other such metals, and it would have been a hollowed out piece of chalk used as an ingot mould. The duplicitous canon, when out to dupe his victim, puts base metal such as copper into a crucible, then adds the special powder. After some suitable heating time, he casts the metal into the chalk stone mould.
However he has previously made an identical silver ingot that looks like it was cast into the same chalk mould that he produced. After casting, he drops the mould and metal into a bucket to cool, but also drops the silver ingot from his sleeve and when fetching the cooled copper ingot produces the silver one instead, to the amazement of his victim, who then demands to know more about how to produce silver from copper and can be persuaded to part with a great deal of money to find out more.
Interestingly, the tale also mentions the use of coal in the fire. I knew that coal was being transported from Newcastle to London in that century, but this is another example of the small bits of cross correlation you can get from reading old manuscripts. Looking further on the internet, I find suggestions that several thousand tonnes was being shipped out of Newcastle in 1300, and that coal was used by blacksmiths from around 1200 onwards.
Given that Chaucer started writing the Canterbury Tales in the 1380’s, I think it fair to suggest that the tale represents what was known amongst well educated sections of society in the 2nd half of the 14th century. (Chaucer wrote a treatise on the use of the Astrolabe in 1391) The Alchemy craze in medieval Europe really got going in the 13th century, and possibly had reached its first peak when Pope John 22nd issued a Bull against it in 1317.
Re-enactment camp
This is therefore within the time period of our re-enactment group, and gives some licence for practising Alchemy at that time. The tricky bit is in fitting it into the camp activities in a half way acceptable manner. Also it seems clear that most practitioners in the 14th century were churchmen of some sort or another, and further research is required into the precise standing of such nebulous people as the duplicitous Canon in the story. But on the other hand the basics of alchemical practise are clearly laid out, with my display requiring distillation apparatus, crucibles, a good furnace, tongs, grinding equipment, clay and glass vessels for liquids and heating substances on the fire.
As a cautionary ending, the Canons yeoman says in his tale (modernised spelling):
“This wicked craft, whoso will exercise, he shall never gain wealth that may suffice; for all the coin he spends therein goes out and is but lost, of which I have no doubt. understand these things what the actual processes are that are used in all painting and other kinds of work.”
