Category Archives: distillation

The “Gentle Heat” of Boerhaave’s Little Furnace

By Ruben Verwaal and Marieke Hendriksen

Ruben Verwaal is curator of the historical collections at Erasmus Medical Centre, Rotterdam, and at the Museum for Communication in The Hague. He obtained his PhD in June 2018 with a thesis on the role of bodily fluids in eighteenth-century chemistry. Marieke Hendriksen is a postdoctoral researcher on the Artechne Project at Utrecht University and a long-time contributor to The Recipes Project. She specializes in the material culture of science and art in the long eighteenth century. Ruben and Marieke share an obsession with an eighteenth-century object that has since disappeared: a small chemical furnace.

With the introduction of chemistry into the university curriculum in the late seventeenth century, new practical needs arose for students  such as being able to perform experiments. Would it be possible to build a chemical furnace that provides a gentle heat, yields no smoke, and is safe for students to use? Herman Boerhaave (1668–1738) believed he found the perfect solution in, what came to be called, Boerhaave’s little furnace.

Portrait of Herman Boerhaave by Cornelis Troost, c. 1730.

Boerhaave was professor of medicine, botany and chemistry at Leiden University in the early 18th century.[1] Instead of starting with the most difficult experiments with metals and minerals, he was convinced that students were better off when they learned the techniques of through simpler processes, such as distilling leaves and flowers, and fermenting bodily fluids. But most chemical laboratories were equipped with elaborate devices too complicated for freshmen students, who in the eighteenth century could be as young as fourteen. Moreover, the brick-build furnaces were designed to create high temperatures, in which small and delicate materials like rosemary leaves would burn instantly.[2] Boerhaave hence needed a device that was low-cost, user-friendly, and would provide a gentle heat.

The plan for the oven, • H. Boerhaave, Elementa Chemiae, Quae Anniversario Labore Docuit in Publicis, Privatisque Scholis, (Leiden 1732).

A small wooden oven was the answer. Boerhaave claimed he had designed this type of furnace when he himself was studying chemistry in the 1690s. He opened the chapter on instruments in his chemistry textbook with the words: “I shall begin with my simplest furnace; which I invented forty years ago, when I practiced chemistry in no large study, where there was only one little chimney, and where I required several furnaces at once.”[3]

Woman at the Virginal and stove under her feet, by Jan Miense Molenaer, 1630-1640. Rijksmuseum, Amsterdam.

This kind of device was probably inspired by ordinary foot stoves. These little stoves, also known as foot warmers, were very popular in the Dutch Republic. Coming in a wide variety of shapes (square, octagonal, cylinder), these stoves often feature in books and paintings. Filled with glowing coals or peat, women placed the little stoves under their robes or blankets to keep warm.[4] Many foot stoves were equipped with a wire bail handle for lifting and easy transportation. Such stoves were used in carriages, sleighs, at home and in church to keep one’s feet warm. This ordinary foot warmer got new applications too, namely as tea and coffee stove,   and we suspect it was the model for the ‘simplest furnace’ in the Leiden chemical laboratory.

Woman carrying a little stove, Harmen ter Borch, 1648–1677. Rijksmuseum, Amsterdam.

The gentle heat produced by Boerhaave’s small oven proved very useful in performing all kinds of chemical experiments. Take rosemary, for example, the evergreen aromatic shrub. Distilled atop a “violent fire”, it would have been turned to flame, smoke, and ashes. But when rosemary instead was distilled at “summer-heat” (approx. 85º F), the mild operation would instead reveal the most volatile, fragrant and aromatic part of the plant ordinarily exhaled in summer. The same process could be applied to Angelica, basil, and all other aromatic plants.

Students in the Leiden laboratory, in Herman Boerhaave, Institutiones et experimenta chemiae (‘Paris’, 1724). Ghent University Library.

Boerhaave, in other words, attributed the success of his device to one’s control over gentle heat. Whenever the wooden oven was filled with hot pieces of coal or Dutch turf that was no longer smoking, it established a constant and moderate heat that could be kept up to 24 hours. As such, the instrument was perfect for students to perform all kinds of heating processes and distillations. In fact, he was so excited about this apparatus, that he claimed that “I believe eggs may be hatched by it”.[5]

Was Boerhaave’s little furnace really that user-friendly and effective as he claimed it was? We checked it out by recreating Boerhaave’s stove and performing experiments with it. Check out our next blog to entry to find out whether we succeeded!

Creating an oven from two old stoves… to be continued!

References:

[1] More on Boerhaave, see Marieke Hendriksen, “Boerhaave’s Mineral Chemistry and Its Influence on Eighteenth-Century Pharmacy in the Netherlands and England”, Ambix(2018) and Ruben Verwaal, “The Nature of Blood: Debating Haematology and Blood Chemistry in the Eighteenth-Century Dutch Republic”, Early Science and Medicine(2017).

[2] Boerhaave, Elementa Chemiae (Leiden:  Isaac Severinus, 1732), vol 2, experiment 1.

[3] Ibid., vol 1.

[4] Le Francq van Berkhey,Natuurlyke historie van Holland (Amsterdam: Yntema and Tieboel, 1769–1778), vol. 3, 706-707, 1200.

[5] Boerhaave, Elementa Chemiae, vol 1.

Tales From the Archives: A Recipe for Disaster: How Not to Distill Turpentine

In September 2018, The Recipes Project will be six years old. There’s been a lot of blogging on this platform, and we are so grateful to all our wonderful contributors. But with so much material on the site, it’s easy for earlier pieces to be forgotten. So, the editors have decided that, once a month, we’ll pull something out of the archives to share with our readers anew.

This month, I have chosen a piece written by Tillamann Taape. In this post, first published in July 2013, Tillmann writes vividly about alchemical disasters. Heat, unsurprisingly, comes into play. Enjoy!

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

By Tillmann Taape

When sifting through early modern alchemical recipes, I am often struck by their inherent dangers which would make modern-day health and safety officers pull their hair out. Renaissance practitioners were remarkably unfazed by temperatures high enough to melt glass and metal, and they frequently recommended heating volatile and flammable liquid in sealed glass vessels which, by their own admission, had a tendency to crack if not handled with the utmost care. Surely these exploits must have gone wrong a lot of the time, resulting in burnt fingers or a faceful of boiling alcohol?

If we look at the stereotype of the alchemist in contemporary satirical literature, it seems that accidents came with the job. In his Ship of Fools (1494), German humanist and satirist Sebastian Brant echoes themes from medieval poetry in his depiction of the alchemist: a greedy and reckless fool whose dangerous and fruitless exploits leave him scarred, financially ruined and even blind. [1] As a source of historical information, satirical genres should of course be taken with a generous pinch of salt. It is significant to note, though, that early modern people saw alchemy as a potentially dangerous thing to do, even in times long before anything like today’s health and safety standards.

More direct evidence of alchemical disasters is, unfortunately, fairly rare. I would of course be delighted to be persuaded otherwise by readers of this blog, but to me it seems that while adepts of alchemy frequently wrote down instructions which sound like they might well blow up, they were frustratingly silent on whether this actually happened. I was quite thrilled, therefore, when I finally stumbled upon a first-hand account of an alchemical disaster: exploding stills, knocked-out practitioners and all. In his 700-page tome entitled Liber de arte distillandi de compositis or Large book of distillation, first published in 1512, my favourite surgeon-apothecary Hieronymus Brunschwig (introduced here and here) includes the following cautionary tale.

Brunschwig was distilling turpentine to separate the watery fraction from the valuable oil, and when nearly all of the water had come out, he was interrupted.

 I was called away to a patient, so the oil went into the water, and when I came back, a layer of oil was sitting on top of the water. I didn’t have the sense to simply decant off the oil, so I poured the lot into a new flask and thought I’d just extract the water by distillation. But I was called away again, and in the meantime the water evaporated from the oil, and some of it condensed on the side of the flask and dripped back into the oil, which rose inside the flask with a great tumult, and fumes erupted from the flask, blowing off the alembic. [2]

 A lot to handle: picture of a still from Brunschwig’s Large book of distillation. © Wellcome Images

A lot to handle: picture of a still from Brunschwig’s Large book of distillation.
© Wellcome Images

Things got worse when Brunschwig came back late at night and went to investigate the accident, telling his servant to bring along a light:

When the light arrived, the fumes touched it, and fire burst forth all around, and in the blink of an eye went out again, nevertheless burning off mine and my servant’s hair, clothes and eyebrows. We fell to the ground and did not know where we were, but before long we got up again and fetched a closed lantern so the same thing would not happen again, and threw ashes in the furnace to smother the fire. [2]

And this, dear readers of the Large book of distillation, is how you do NOT distill turpentine! Once the initial excitement about this truly adventurous tale had worn off, I realised that, to the historian, there was more to this anecdote than merely the satisfying confirmation that some procedures which look so precarious on paper did indeed go up in fire and smoke. In his description of this extraordinary incident, Brunschwig also reveals a number of interesting details about his everyday life and work. We get a glimpse of what it meant for an early modern practitioner to have multiple vocations. Juggling his alchemical activities with his duties as an apothecary and surgeon, it seems that Brunschwig could be called away to the aid of a patient at a moment’s notice, even at night. We also learn that he had at least one servant, and we can surmise that he did his distillations in an enclosed workshop, since a buildup of explosive fumes would be unlikely in the open air. Perhaps most importantly of all, this anecdote provides strong evidence that Brunschwig was actively performing many of the procedures he describes in his works, rather than just copying and compiling them for publication.

Anecdotes like these, then, are more than just an entertaining read and a well-earned reward for ploughing through hundreds of pages of Brunschwig’s Alsatian dialect with its erratic spelling. Descriptions of extraordinary events also grant us a glimpse into the reality of practicing alchemy, and into practitioners’ everyday life.

[1] On the stereotypes and changing ‘personae’ of early modern alchemists, see Tara Nummedal,  Alchemy and Authority in the Holy Roman Empire. Chicago: University of Chicago Press, 2007, Ch. 2.

[2] Brunschwig, Hieronymus. Liber de arte distillandi de compositis […]. Strasbourg: Grüninger, 1512.

 

Recipes for honey-drinks in the first published English beekeeping manual

By Matthew Phillpott

The Roman emperor Augustus is said to have asked the Roman orator, poet, and politician, Publius Vedius Pollio, how to live a long life. Pollio answered that ‘applying the Muse water within, and anointing oil without the body’ would help to keep him free of sickness. Whether Augustus took up Pollio’s advice is not mentioned. Indeed, Thomas Hill was little interested in exploring the story further when he took it from Pliny the Elder’s The Natural History in the 1560s as part of his small treatise on beekeeping, A Pleasant Instruction of the Perfect ordering of Bees (London, 1568).

Drawing of Thomas Hill from his The Art of Gardening (1568).

The story’s purpose, as an opening passage of his twenty-ninth chapter, was meant only to introduce Muses water (otherwise called Melicrate by the Greeks or more commonly, Hydromel), and to suggest that it is a drink containing various health benefits. Hill went on to explain that the Muses water can ‘ease the passage of wind or breath, soften the belly’ and cure poisoning by Henbane. He then gave a recipe;

Let eight times so much water be mixed unto your honey prepared which boil or seethe so long, until no more foam arises to be skimmed off, then taking it from the fire, preserve to your use.

Hill provides no more detail than that, but he does go on in the next chapter to give a recipe for Oenomel – ‘a sweet wine made with honey’ – that he says is ‘not only for the preservation of health but also to expel the torment of sickness’. Hill advises his readers that the best Oenomel is made of ‘old and tart wine’ with ‘the best purified honey’. His recipe;

Take one gallon and a quart of wine and mix it with half a gallon and a pint of the best honey.

There are more recipes in Hill’s treatise on beekeeping. There are several that describes a distillation of the honey, and another that describes the making of a Honey Quintessence.

Hill’s manual was the first handbook published in English about beekeeping, and it was attached to the very first handbook on gardening (The Profitable Art of Gardening), also produced by Hill. The purpose was a simple one: to bring the knowledge of ancient authorities such as Aristotle, Pliny the Elder, and Virgil, to a modern audience as a means of providing ‘their knowledge and experience’ for the profit of ‘poor husbandmen’ and the better wealth of England more generally.

It seems likely that the recipes for Hydromel and Oenomel were common knowledge and all Hill did here was to cite an authority for something that was already known (he cited Paul Aegina – a 7th-century Greek physician – and Pedanius Dioscorides – a 1st-century Greek physician and botanist). The recipes for distillation and Quintessence were more advanced and might well have been one of the earliest published recipes for these drinks in the English language (although again, the general principles were likely well known).*

By including recipes in his book, Hill emphasises the benefits of beekeeping for his readers but also makes the manual useful beyond those strictly interested in managing a swarm of bees. Landowners or their land managers, who purchased the book to improve the gardens, might equally pass the knowledge of honey recipes to others in gentry households. It would be fascinating to discover if any manuscript recipe books from this period contained references to Hill’s honeyed-drinks or whether any copy of Hill’s books contains annotations or bookmarks related to the recipes.

At the very least, by initialising the genre of beekeeping manuals in England, Hill provided precedence in terms of the structure of content, if not in detail. Many of the beekeeping manuals published in the seventeenth-century also contained recipes for honeyed-drinks and many followed a similar structure to the one that Hill provided, even where they disagreed with many of his claims. How many people followed the recipes, however, is another question entirely.

* Quintessence was described by Andreas Vesalius in 1551 in a book called A compendious declaration of the excellent virtues of a certain lately invented oil, called for the worthiness thereof oil imperial.  He described the Quintessence as ‘nothing else but aqua vitae’ (i.e. distilled wine), and does not mention honey. In 1559, Konrad Gesner’s The Treasure of Euonymus included a much more detailed description of types of Quintessence as drawn out of wine made from a variety of wood, fruits, flowers, oats, leaves, seeds, stones, metals, flesh, and spices. There is a brief mention of honey quintessence, but not a specific recipe for it. I have yet to find any other English printed work before 1568 that describes Honey Quintessence in any kind of detail.


Matthew Phillpott lives in the United Kingdom and undertook studies in early modern history at Hull and Sheffield. He now works at the School of Advanced Study, University of London, and in addition investigates early modern printed materials for ideas about knowledge, history, culture, health, and food. He has recently started a new website to talk more about his research into bee culture in the early modern period called Early Modern Bees.

 

 

‘This one is good’: Recipes, Testing and Lay Practitioners in Early German Print

By Tillmann Taape

Title illustration from Brunschwig’s Small book of distillation. © Wellcome Images

Having recently finished my doctoral thesis on the printed works of Hieronymus Brunschwig, which have previously featured on the Recipes Blog (here and here), I am delighted to contribute to this series of posts on testing and trying (for an overview, see our re-posted summary of the Testing Drugs and Trying Cures conference). What better opportunity to share how it all came together, and reflect on the role of recipes and testing in the narrative.

Hieronymus Brunschwig (c.1450–c.1530), a surgeon and apothecary from Strasbourg, wrote the first printed books on surgery and distillation. In my thesis, Hieronymus Brunschwig and the Making of Vernacular Medical Knowledge in Early German Print, I read these uncommonly practical and technical books alongside records from the Strasbourg archives, about the craft guilds and medical practice. This allows us to make sense of Brunschwig’s practical vernacular medicine in relation to local intellectual trends, different forms of healing, the local milieu of guilds and artisans, and early German print culture.

Brunschwig’s first book was the Cirurgia of 1497, the first surgical manual in print. This, of course, was an opportunity to codify and re-define surgery. Brunschwig revives the medieval tradition of what Michael McVaugh has termed rational surgery (i.e. a learned as well as a practical art), to educate trainee surgeons and to present their discipline as a respectable and useful trade. Emphasising the need for skilled hands as well as a working knowledge of the human body, Brunschwig defends surgery on two fronts: against learned physicians’ rhetoric of superiority, and against other craftsmen’s deep-seated anxieties about occupations which were in contact with sick and dead bodies.

A surgeon treating an abdominal wound. Hieronymus Brunschwig, Dis ist das Buoch der Cirurgia (Strasbourg, 1497). © Wellcome Images.

The later books on distillation, published in 1500 and 1512, open up to a wider readership, including not only medical artisans such as surgeons or apothecaries, but also the ‘common man’ – a middling social layer of literate citizens, householders and other lay practitioners. This new kind of medical reader, as I have discussed in a previous post and elsewhere, is emblematised in the figure of the ‘striped layman’ which appears in numerous woodcut illustrations throughout Brunschwig’s works.

A conspicuously stripy student, from Brunschwig’s Cirurgia (1497). © Wellcome Images

Many of the recipes and instructions in the distillation books are adjusted for this type of reader. They start from scratch and are rich in technical details which are not found elsewhere in print or, to my knowledge, in manuscript. Although Brunschwig engages with complex ideas about the nature of matter and its manipulation, such as John of Rupescissa’s notion of a ‘quintessence’ in all things, he re-works them into manageable, pedestrian remedies. Rather than pursuing Rupescissa’s heavenly panacea, Brunschwig uses distillation to produce a type of middle-class quintessences: although earth-bound and imperfect, they were reliable and effective remedies in the hands of laypeople.

Detailed woodcut images of distillation apparatus and instructions for its use. Brunschwig, Liber de arte distillandi de simplicibus (Strasbourg, 1500). © Wellcome Images.

One overarching theme of my thesis is the artisan’s approach to understanding and manipulating nature. For a craftsman with no Latin, Brunschwig mined a surprising amount of knowledge from texts. But more importantly, I argue, he knew things through direct physical engagement with bodies, materials and technical processes. His books are full of instructions to probe wounds, check temperature by touch, inspect colour changes in the alembic, and smell or taste distilled remedies. His expertise was located as much in the body and its senses as in books.

Nonetheless, writing was a powerful tool for recording and communicating practical insights. From cautionary tales of exploding alembics to heroic accounts of successful cures, Brunschwig emphasises his own experience as a source of knowledge. The German term he uses for this type of knowledge, erfarung, is related to fahren, meaning ‘to travel’. In the early sixteenth century, it denoted a way of experiencing the world through one’s own senses, by moving through it or simply being in it in an active, attentive manner. Erfarung was compared, often unfavourably, to spiritual contemplation and introspection. Over time, however, doctors and students of nature such as Paracelsus came to see personal erfarung as the necessary labour of insight rather than a sinful distraction. The Book of Nature, they insisted, should be read with one’s feet. Brunschwig’s emphasis on his own and others’ erfarung was thus part of a larger vernacular culture of experiential knowledge, as well as learned debates about experientia which have often been the focus of historical accounts of a medical empiricism developing in the early modern period.

Recipes played a major part in Brunschwig’s codification of experiential medical knowledge. Some, as I have shown in a previous post, were presented in Latin pharmaceutical jargon likely unknown to laypeople. These recipes were closed to readers, who were meant to copy them out on a piece of paper and hand them to an apothecary who would manufacture the remedy according to his art and his experience. Although the great majority of recipes are in German, some of these are also presented as tried and tested, by Brunschwig himself or others, and do not call for ‘tweaking’ on the part of readers.

Other recipes, however, give alternative ingredients or leave the exact composition up to the practitioner’s judgment. Many recipes come without the author’s seal of approval, and their sheer number makes it seem unlikely that Brunschwig could have tested each one. Such ‘open’ recipes leave room for improvisation and testing. The ongoing work of erfarung runs on into readers’ own practice, and often spills out into the margins of Brunschwig’s printed books. In many surviving copies, early modern healers from different walks of life marked recipes with a magisterial probatum est, or a simple vernacular note such as ‘this one is good’.

In some of the earliest medical works in print, Brunschwig addresses a readership of lay healers and ‘common men’ which would come to represent a significant portion of the early German print market. Through his use of recipes embedded within a culture of erfarung, he involved his vernacular readers in a continued effort of empirical trying and testing.

Pursuing the themes of recipes and artisanal knowledge, I am delighted to be joining the Making and Knowing Project at Columbia University this summer, and look forward to sharing our work on making, testing, and trying, which has previously featured on this blog.