Category Archives: Marieke Hendriksen

HEAT! A Recipes Project Thematic Series

Astronomy- the Earth and the sun during summer in the Northern hemisphere. Wellcome Collection.

As humans, we want to control heat. We want to create heat, temper or even extinguish it, depending on context and purpose. We have a very limited temperature range at which we are comfortable (some microbes and bacteria can survive temperatures as low as -20C and as high as 130C), so we spend an incredible amount of time managing heat, whether it is our body temperature or that of our homes, offices, laboratories, cars, or food.

When we started planning this series of blog posts in early May, we could not have suspected how appropriate the theme would feel by now. While much of northwestern Europe has not seen rain in weeks and is sighing under a heatwave with temperatures rising to 37C/98F, we have fled to airconditioned spaces to edit the posts. Climate-wise, heat is seasonal in these regions, but it has always played an important role in recipes year-round, all around the world, from antiquity to the present day, in fields as diverse as alchemy, chemistry, art, cooking, medicine, and personal grooming.

The common denominators of heat in all these realms are that it is either internal – emanating from the human body – or external, naturally occurring from the sun, thunder, or lava, or man-made through friction or fire. In the posts in this series, we will see a wide variety of attempts to control these different kinds of heat through recipes and instructions.

Managing natural heat: Venice turpentine is a thick paste (aka sticky mess) at room temperature, but becomes fluid around 25C, and nicely mixes into the rest of the varnish ingredients when left out in the sun. Photo: Marieke Hendriksen

Some of our authors recreate such attempts by reconstructing experiments outlined in historical art technical and chemical sources. Indra Kneepkens recounts how she discovered through reconstruction research that sometimes for a recipe to make sense, it should not only be followed to the letter, but also be read between the lines. Ruben Verwaal and Marieke Hendriksen use their experiments with two reconstructions of small chemical ovens to reflect on the role of experimental heat in the development of theories on the nature of life in the eighteenth century. Working in a similar vein but with culinary recipes, Marissa Nicosia, from Cooking the Archive, examines the problem of heat control in her recipe recreation adventures, outlining the challenges of translating cooking instructions meant for the early modern hearth to the modern gas stove.

The four elements, four qualities, four humours, four seasons, and four ages of man. Airbrush by Lois Hague, 1991. Wellcome Collection.

Other authors in the series took our invitation as an opportunity to investigate heat in medical theories across time and place. Aileen Das kicks off this series by arguing that heat occupied a central place in ancient Greek, Roman and medieval Islamicate theories about the human body and its care. Taking on the smelly problem of perspiration and body odor, Cari Casteel reminds us that this issue is as old as mankind and offers several remedies from Roman authors.  Catherine Rider, on the other hand, examines notions of heat in fertility remedies in medieval England, noting that, whilst popular, heat-based treatments (to either increase or reduce heat in the body) were not the only kind of fertility aid available to English couples. The series concludes with two posts focused on fever and disease. Writing on in Late Imperial China, Marta Hanson introduces us to ideas of fever in Chinese medicine. Finally, Nukhet Varlik turns our attention to the ambiguities inherent in early modern taxonomies of infection diseases, exploring fever as a symptom and as a disease category.

We’ve had a great time editing this series – hope you enjoy reading the posts wherever you are. Happy summer and stay cool!

Marieke Hendriksen and Elaine Leong

P.s. We were so inspired by our contributors’ posts that we’ve decided to dedicate the December issue to (you guessed it) COLD!. If you’re interested in joining the conversation, send a short pitch to

The devil is in the details: turpentine varnish

Corrosion cast of bronchi and trachea, possibly from a rabbit, sheep, or dog, 1880-1890
Likely prepared by Harvard anatomist Samuel J. Mixter.
The Warren Anatomical Museum in the Francis A. Countway Library of Medicine

By Marieke Hendriksen

One of the first things you learn when you do reconstruction research is that the tiniest detail can make a difference.

Recently, I wanted to prepare an injection wax for corrosion preparations according to a 1790 recipe. Corrosion preparations are anatomical preparations created by injecting an organ with a fluid coloured wax that hardens. The organ is then lowered into a container with a corrosive substance, such as a hydrochloric acid solution, which corrodes the tissue, leaving a negative image of the veins and arteries of the organ. These preparations were made from at least the mid-eighteenth century, but because of their fragility, very few remain. As they were supposedly difficult to make, corrosion preparations were not only a way of studying anatomy, but also a tool for self-fashioning and establishing one’s status as an anatomist.

I have tried to create an injected preparation in the past.[1]It was my first attempt at reconstruction research ever, and although it served me well at the time, now I do things differently.

Most importantly, I want to stay much closer to the original recipe if possible. When we made the injected preparations in 2012, we used modern substitutes for some historical ingredients for economic reasons, and we did not have the time to study every ingredient in detail, substituting those we could not find directly with something we thought would have pretty much the same effect.

The recipe I want to use, Thomas Pole’s 1790 instruction for making a corrosion preparation, calls for a coarse red wax, made from fifteen ounces of yellow bees wax, eight ounces of white resin, six ounces of turpentine varnish, and three ounces of vermillion or carmine red.[2]The wax, resin, and pigment are fairly straightforward.

What is turpentine varnish though? Back in 2012, we ended up using just turpentine rather than turpentine varnish, and although those injections were not meant to be corroded, we ran into numerous problems. For example, it turned out to be almost impossible to keep the wax and the organs at a temperature at which we could both handle it and have it fluid enough to inject. It made me wonder whether sticking with the original recipe could solve that problem, so I set out to recreate it.

This turned out to be more complicated than expected, as there is not one standard recipe for turpentine varnish. Eventually I found a Dutch recipe from 1832 listing a turpentine varnish to finish display cabinets for natural history collections.[3] The ingredients are a pound of oil of turpentine, 8 ‘loot’ (a loot being 1/32 Dutch pound) of white resin, four loot of Venice turpentine, and ½ loot of aloe or kolokwint. Raw larch turpentine has a high concentration of volatile oils that can be distilled. The fluid part is known as oil of turpentine, whereas the residue left in the retort is usually called resin, rosin, or colophony. Oil of turpentine is the essential oil that remains after distilling raw larch turpentine. Venice turpentine is a thick, viscous exudation from the Austrian larch tree, which is not used as a varnish on its own as it becomes dark and brittle when exposed to oxygen and light. Aloe vera is widely known; kolokwint (the Dutch name for Citrullus colocynthisor bitter apple) less so. It is a plant with yellow fruits that resemble small pumpkins, which are very bitter and poisonous. That quality might explain its presence in a recipe for a varnish that is meant to ward off insects. Powdered aloe is readily available from artist’s material suppliers, so I went with that.

The varnish after 10 hours in the sun. The Aloe is the clearly visible murkiness on the bottom. Photograph: author.

The preparation of the varnish was pretty straightforward: put all ingredients in a bottle, cover, and leave in the sun for a day. The only problem was that I had to wait a week for a sunny day. When it came, I put in the ingredients and just left the bottle out in the sun for a couple of hours, which allowed me to stir the ingredients together. The aloe however did not resolve properly, and just sits at the bottom of the jar. While this might not be much of a problem when the varnish is applied to a cabinet, it makes this particular turpentine varnish unsuitable for use in my injection wax. Next time, I will make another batch without aloe and use that instead.

Why do I recount this–admittedly not very exciting–story? It shows how difficult it can be to follow a historical recipe to the letter. It also shows how much you learn from reconstruction research, even if it does not always yield the results you’d like, or as fast as you’d like.

[1]Marieke Hendriksen, Elegant Anatomy, (Leiden: Brill 2015), pp. 1-9.

[2]Thomas Pole, The Anatomical Instructor ; or an Illustration of the Modern and Most Approved Methods of Preparing and Preserving the Different Parts of the Human Body and of Quadrupeds by Injection, Corrosion, Maceration, Distention, Articulation, Modelling, &C(London: Couchman & Fry, 1790), pp. 21-5, 122-42.

[3] S. de Grebber, Over de schadelijke huisinsekten, als de huisvliegen, wespen, muggen, weegluizen, vlooijen, luizen, motten, pels-, boek- en kruidkevers en wormen, hout-, blad- en schildluizen, plantmijten enz., met aanwijzing van voldoende en proefhoudende middelen, om dezelve geheel uit te roeijen, Volume 1,(Amsterdam, 1832), pp. 52-3.

Indigo or no indigo?

Marieke Hendriksen

Fermenting indigo at Ock Pop Tock, Laos. January 2018.

When you say indigo, the first thing many people will think of is blue – jeans blue. (Or if you’re me, you’ll think first of a seventeenth-century recipe to make decorative blue prunes from wax with indigo. Occupational deformation.) But historically, indigo has been used in many more ways, and to make more dye colours than just blue, as I recently discovered. Today, most jeans are died using a synthetic blue dye, but indigo dyes, made from some of the over 750 species of the genus Indigofera as well as from some other plants, have been used to dye textiles for at least 6,000 years, while other subspecies of Indigofera were traditionally used as analgesics with anti-inflammatory properties.

The term ‘indigo’ according to the OED started to occur from the sixteenth century onwards in various European languages to denote blue dyes from India (or east Asia more generally), but can now also refer more generally to dyes, violet-blue light, or blue hues. It might be argued that the term only really applies to dyes created from Indigofera subspecies, while it could also be said that indigo is any dye created from plants through the decomposition of the glucoside indican, which exists not merely in the indigo-plant, but in woad and various other plants too.

Wash the freshly picked leaves…

While on holiday in Luang Prabang, Laos, I took a weaving and dying workshop with Ock Pop Tock, an organization that was established to preserve the traditional Laotian craft of making hand-loomed textiles. There, I discovered that there is more indigo besides Indigofera, and that one indigo plant can give many more dyes than just blue. They also have a wonderful informative website on natural dyes. At Ock Pop Tock, the plant species used to create indigo dyes is Persicaria tinctoria, or long leaf Japanese indigo, a plant indigenous not to Japan but to China, Vietnam, and Laos. Depending on how the leaves are treated, it can be used to create blue, green, black, and mauve.

…give them a good pounding to create a dye.

Using the fresh leaves creates a green dye, fermenting them for at least five days and adding limestone as a mordant gives a blue dye. Traditionally, the Lao believed that the dye was female, and that it fermented because it attracted a male spirit. To coax the spirit, the pots containing the dye would be dressed in a skirt, and a knife placed on top of the lid to ward off evil spirits that could ruin the dye. The fermentation is actually a naturally occurring oxidation process, with atmospheric oxygen as the oxidant. Regular stirring ensures the process continues. The longer the indigo mixture is left to ferment, the darker it turns. If this mixture is boiled, it turns black. Alternatively, a rare indigenous plant, mak bow or bow vine, can be added to the blue dye to create mauve.

The end result: a beautiful scarf

As part of the half-day workshop, I got to dye a silk scarf with a dye of my choice. I love green hues and wanted to make a dye from start to finish, so I chose to dye my scarf ‘indigo’ green. This was, apart from some pretty intense pounding of leaves, surprisingly easy. I got to pick fresh Persicaria tinctoria leaves in the beautiful garden, washed them, and mashed them vigorously in a mortar for about five minutes. Then I transferred the mashed leaves into a tub, added some cold water and then the raw silk scarf. After kneading the dye into the fabric for a couple of minutes, I could rinse my scarf and hang it to dry. The end result is a beautiful soft green scarf, that is not just a souvenir, but a tangible reminder of the traditional Laotian knowledge about natural dyes preserved and shared at Ock Pop Tock.

Teaching a Perfect Knowledge in the Arts and Sciences: Robert Dossie’s chemical, pharmaceutical, and artistic handbooks

Front page to a 1796 reprint of Dossie’s Handmaid

By Marieke Hendriksen

Robert Dossie (1717-1777) was and English apothecary, experimental chemist, and writer. Within just three years, he published three very successful handbooks: The elaboratory laid open (1758) on chemistry and pharmacy for ‘all practitioners of medicine’, Theory and practice of chirurgical pharmacy (1761) for surgeons, and The handmaid to the arts (1758), which taught ‘a perfect knowledge of the Materia Pictoriae’ such as painting, gilding, and japanning. Gibbs (1951, 1953) has written a short overview of Dossie’s life and work, with a focus on his role in the Society of the Arts, but paid no attention to the cohesion of his seemingly divergent work.

Lowengard (2006) has briefly noted that Dossie used a form typical for books about materia medica for his book on the arts, grouping the contents according to techniques employed as well as by the media to which they might be applied, yet his work has never been thoroughly analyzed. Did Dossie indeed transmit a way of structuring and presenting practical knowledge in text from one realm to another? Recipe collections and how-to books before the eighteenth century were often a mixture of medicinal and artisanal recipes and instructions, and the boundaries between medicine, chemistry, and the preparation and application of artist’s materials often so fluid as to be almost non-existent.

Moreover, some earlier printed books on painting and dying techniques did employ the format of a systematic discussion of materials and their preparations, followed by their application, for example Willem Goeree’s 1760 Verlichterie-kunde  What was novel about Dossie’s Handmaid of the Arts though was the combination of this way of presenting practical artisanal knowledge, his attempt to be encyclopaedic in his collection – listing the uses of the same base materials in the production of various artistic and decorative objects, and his very intentional use of the term ‘Materia Pictoriae’.

Rubia tinctorium (madder), one of the many plants that was both materia medica and materia pictoria

The latter appears to have been an attempt to subtly elevate the status of the visual and decorative arts by paralleling the materia pictoriae to the materia medica. Finally, the intended audience gives us more insight in how Dossie understood his own work. From the preface of the book, it appears that Dossie did not so much aim at the people creating visual and decorative objects, but at the professional preparers of artist’s materials, of whom he wrote: “a much greater share of knowledge in natural history, experimental philosophy, and chymistry, is required to the understanding the nature of the simples [sic], and principles of the composition, in a speculative light, than is consistent with the study of other subjects more immediately necessary to an artist.” (p. vii-viii)

In eighteenth-century England, high street chemists and druggists were evolving from preparers and sellers of chemical substances to compounders, stockists, and sellers of drugs and dispensers of medical advice, and it is in this light that Dossie’ work and his division between materia medica and materia pictorial must be seen. Did Dossie intentionally and successfully adapt and implement formats and language traditionally used in one field (medicine) for the organization and transmission of practical knowledge in text to others (chemistry and the arts)? To me it appears that in his mind, materia medica and materia pictoriae were both branches on the tree of chemistry, and that his corpus, which we now tend to see as divergent, was actually a cohesive body of work to him and his contemporaries.


Dupré, Sven, ed. Laboratories of Art : Alchemy and Art Technology from Antiquity to the 18th Century. Archimedes 37. Cham [u.a.]: Springer, 2014.

Gibbs, F.W. “Robert Dossie (1717–77) A Further Bibliographical Note.” Annals of Science 9, no. 2 (1953): 191–93.

Gibbs, F.W.  “Robert Dossie (1717–1777) and the Society of Arts.” Annals of Science 7, no. 2 (1951): 149–72.

Lowengard, Sarah. The Creation of Color in Eighteenth-Century Europe. Columbia University Press, 2006.

Worling, Peter M. ‘Pharmacy in the Early Modern World, 1617 to 1841 AD’, in Making Medicines: A Brief History of Pharmacy and Pharmaceuticals, ed. by Stuart Anderson (London: Pharmaceutical Press, 2005), pp. 57–76.