On twitter recently a new article with the above self explanatory title was mentioned, written by Christopher Booth and published in The Journal of medieval Monastic studies, Volume 6, 2017.
The starting point for his paper is the venerable but still interesting paper on “Medieval distilling apparatus of Pottery and Glass” in 1972 by Stephen Moorhouse. This brought together a number of sites on which evidence for distillation had been found and as such was intended to spur more research. Booth points out that unfortunately not a lot has been done since then, so his paper tries to carry things further. He deliberately brings alchemy into the discussion from the start, but I think we can skip over his explanation of early alchemy and get into expanding and discussing the rest of it.
He points out that “The two most significant distillates of later centuries, mineral acids and alcohols, were likely only discovered within Western Europe in the twelfth century, as recipes for their production only became common by the thirteenth or fourteenth centuries”
His references are to Anderson in “Instruments and Apparatus”, Forbes, “A short history of the art of distillation and Multhauf “the origins of Chemistry”
The latter two are ancient works, very out of date. It is a sad fact that there hasn’t been a work pulling together all the research done since Forbes wrote his book. If anyone wants to give me money to write it I’d be happy to do so, but what a history of distillation in Europe and the middle east needs is a multi-lingual team and 5 years.
As for the distillation of alcohol, I am persuaded by the chapter in Ahmad Y. Al-Hassan’s book “Critical issues in Latin and Arabic Alchemy and Chemistry” that distillation was practised in the middle east by the 8th century, and from there it would have been transferred via Sicily and Spain to Europe. He quotes various texts and if you read any Arabic alchemical text you will find many references to distilling pretty much anything that could possibly be distilled, solid or liquid. Even without textual evidence, there is no reason to suppose that people didn’t distill wine.
There is also C. Ann Wilson’s book “Water of life” which suggests distillation of wine was carried out as a great secret thing, IIRC, 2000 years ago, the knowledge kept within secret societies and religious organisations, although it is on somewhat shakier ground.
Certainly the distillation of wine to make alcohol was written about and known in Spain and France in the 13th century, e.g. the works of the real Arnold of Villanova. So it would have reached England by the 14th century, and I am sure I have read about it also being transmitted via 12th century Salerno in Sicily.
The tricky bit is mineral acids. Al-Hassan tries to claim them all for Arabic chemistry. I have tried some recipes that he quotes and reckon most wouldn’t have worked (https://distillatio.wordpress.com/2013/03/20/not-one-of-the-earliest-recipes-for-making-acid-the-humbled-chemist/), and wrote a while back that they were invented in western Europe, probably Spain, (https://distillatio.wordpress.com/2013/09/17/the-invention-and-manufacture-of-mineral-acids-in-medieval-europe/) but I suspect that the original discovery might have been in Arabic Spain.
Anyway, back to the paper. I like the idea of using cupellation and sublimation as markers, it makes sense and can guide analytical approaches to the archaeological finds. Booth is correct that sublimation is more likely a marker of alchemy than of chemical techniques.
Data from 23 published sites is used in the paper, and notes that there isn’t overlap between the different things done at each site, as in, you don’t find distillation and cupellation at the same site.
At this point I should pause and run off and find a copy of an article on pewter stills that he mentions, by Hayward and Hayward in the Journal of the Pewter Society.
Booth mentions that alembics have been misidentified, which is always an issue.
Cupellation is discussed well enough, and of course Oberstockstall comes into it, because that site contained evidence for all parts of the alchemical work, including silver cupellation. Cupellation in an alchemical work is usually carried out either to ensure you start with pure silver, or else to test the silver that you have made.
The discussion section is where things are brought together.
Booth is correct to say that there are 4 possible reasons to find such artefacts on a site, the first being that it was a manufacturing site e.g. of distillation apparatus, second that they were used in a kitchen to make consumable products, which applies to distillation, or three, it was used for alchemical experiments, or four they were used in metallurgy. Regarding point three he mentions Jenny Rampling and her work on Ripley as indicating that alchemy was practised in monasteries and priories. He might also have included Chaucer’s Cannon’s Yeoman’s tale, and there is a telling mention of an alchemical laboratory in Walsingham priory, in 1538, when commissioners looking for valuables to remove found a ‘”secrete privye place within the howse, …, in which there were instrewmentes, pottes, belowes, flyes of such strange colers as the lick non of us had seened, with poysies and other things to sorte, and denyd gould and sylver, nothing ther wantinge that should belonge to the arte of mulyplyeng.”
On cupellation, Booth points out that the hearths with potential cupellation evidence belong to the dissolution of the monasteries period, which would make sense, and that they were more likely for lead recycling. On the other hand, he doesn’t give a reference for the claim that “… the lead from the monasteries that we being recycled would undoubtedly have had any silver content removed previously…” which I think isn’t quite right. Methods of smelting lead ore and testing for silver had varied over the medieval period and improved by the 16th century. I am sure I read somewhere about older medieval lead having the silver removed, but I can’t remember where.
The above photo is a cupel I made, and used to get the nice pure blob of silver in the middle. The black stuff around it is metal oxides from the lead and air, that used to be in the silver.
The two sites with evidence for cupels, at Portmahomack (I’ve visited it, nice wee museum in the old church), and Armagh, are quite early, Armagh being 5th to 7th centuries, and Portmahomack similar. Whilst mentioning that metalworking apparatus was found too, Booth perhaps should have said outright that the evidence supported purification of silver for use in decorations and such associated with the monastery. For this, “On Divers Arts” by Theophilus, from the 12th century, is the go to book. It mentions cupellation, for purifying silver with which to make a chalice, and says to use ashes for it, although it is unclear whether they are wood or bone. From what I have read, a lot of monasteries were centres of industry and craft work, at least during the early medieval period, since they retained some of the expertise of the Roman era that was lost elsewhere. Thus to say that “The scarcity of cupellation vessels at monastic sites is possibly explained by the fact that in monastic precincts the only uses of cupellation that are likely are small-scale assaying of ores for economic or alchemical purposes.” is incorrect. Portmahomack also fits into the general fact that in early medieval Scotland artisans using bronze and silver were found working at places of governance and elite residences.
Pure silver is softer than the alloy and thus more easily worked for certain decorative purposes, and as I have said above I think it likely the cupellation is for manufacture of items. “On Divers Arts” certainly counts as another way of looking at monastic cupellation that doesn’t require material culture.
The discussion of sublimation is interesting. I would say that glass can survive the temperatures needed for sublimation; it’s specified for making acids too, if you lute it up properly.
Unfortunately the possible sublimation vessel has not been properly published, again showing the poor state of a lot of archaeology in the UK, despite it’s popularity with the public.
He is likely correct to say that sublimation before the 15th century is most commonly used in alchemical experimentation. It took a long time for alchemical knowledge to spread properly across England. Distillation of wine and suchlike in order to make medicines only really got going in the 15th century, despite being common on the continent before that. I do not recall finding any late medieval English medical recipes that involve sublimed mercury. There is a possibility that it could be used to make cinnabar for artistic purposes, the manufacturing process involving sublimation. The Libellus de Alchimia says to do it in a glass vessel.
In the conclusion, his comments about distillation being more common make sense, as it has non-alchemical uses. We definitely need to re-assess the chemical residues in old and new finds, as per Marcos Martinon-Torres and his work on Oberstockstall. We also need more funding for proper studies of artefacts and assemblages, in order to avoid missing anything.
Hopefully with this as a basis more work can be carried out and archaeologists will be more aware of what to look out for.
Mention is made within the text of distilling apparatus found in excavation of Weoley castle.
These can be seen here: http://www.barbicanra.co.uk/assets/weoley-castle-summary-v2.pdf and more fully here: http://archaeologydataservice.ac.uk/archives/view/weoleycastle_eh_2011/downloads.cfm