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

This post first appeared on The Recipes Project on 5 June 2018.

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 turpentineis 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.

Dark tourism past and present

Last Saturday, the Travel section of my Dutch newspaper, the Volkskrant, featured a short article on ‘dark tourism,’ the phenomenon of people leisurely visiting places that are reminders of death, suffering or the macabre. Examples are Auschwitz, the Anne Frank house and graveyards, but also the Body Worlds exhibitions. According to Philip Stone, director of the recently established Institute for Dark Tourism Research (iDTR), dark tourism is increasing in popularity, something he ascribes not only to marketing but also to secularization. As churches empty, people seek other places to think about life and death, good and evil, he suggests in the article.

However, if I learned anything while writing a PhD thesis about eighteenth century anatomical collections, it is that there is nothing new about dark tourism. In seventeenth- and eighteenth century Leiden for example, the anatomical theatre and its collections were one of the biggest tourist attractions. Guides were published in Dutch, Latin,

Visitors can be seen strolling around and pointing out things to each other. The dissected body on the table is unlikely to have been there during the summer tourist season in reality, as dissections were normally only performed during the cold winter months.
Visitors can be seen strolling around and pointing out things to each other. The dissected body on the table is unlikely to have been there during the summer tourist season in reality, as dissections were normally only performed during the cold winter months.

English and French, and paying visitors could join guided tours. These visitors could of course use the opportunity to learn something about human anatomy, but they were also treated to stories relating to the exhibits, such as that of the skeleton of a woman who had been condemned to death for theft. This Catherine of Hamburg allegedly bought a length of ribbon at a market in Amsterdam, measuring from one ear to the other – a standard length. However, after the purchase, she claimed that one of her ears was nailed to the pillory in Hamburg. [1] Although visitors found stories like this one hard to believe sometimes, most of them did not seem to mind a little stretching of the truth if there was a moral lesson or just entertainment.[2]

Title page of an English visitor's catalogue to the Leiden Anatomical theatre, 1727.
Title page of an English visitor’s catalogue to the Leiden Anatomical theatre, 1727.

Yet in the course of the eighteenth century, the attraction of this kind of ‘dark tourism’ was changing, at least in the case of the Leiden anatomical collections. For example, an English visitor who described his stay in Leiden in 1775 stated that “…you must not fail to see the Anatomy-chamber”, but adds this is mainly because that is where “they preserve the money of Egypt; Pagan idols, –foreign dresses, birds from China, &c, &c.” Not a word about anatomical preparations or moral lessons.[3] This indicates that the anatomical theatre to tourists had become a cabinet of curiosities instead of a place to learn about human anatomy and morality. The curators also realized this, and from the last decades of the eighteenth century, the collections were partly handed over to other institutions, such as the newly established museum for antiquities, and the anatomical theatre slowly changed from an open-for-all public attraction into a closed teaching institution.[4]

This story about the Leiden collections shows that what is considered ‘dark’ can change over time, and that the reasons people visit these places vary. Then as now, some want to contemplate life and death or morality, others want to be entertained or learn something about the human body or human behaviour. My guess is that in order for a ‘dark tourism attraction’ to be successful in any time, visitors need to be able to relate to what is on show, or the people whose stories are told by and in that place – hence the massive success of the Anne Frank house and Body Worlds. As long as the story is a universal human one, and credible, visitors will continue to come.


[1] Uffenbach, Conrad Zacharias. Merkwürdige Reisen durch Niedersachsen, Holland und England. 3 vols. (Frankfurt/Leipzig, 1753).

[2] Knoeff, R. ‘The Visitor’s View. Early Modern Tourism and the Polyvalence of Anatomical Exhibits’, in L. Roberts (ed.), Centers and Cycles of Accumulation in and around the Netherlands during the Early Modern Period  (Münster: LIT Verlag, 2011), pp. 155-175, 166-7.

[3] Anonymous. Holland: A Jaunt to the Principal Places in That Country. London: W. Hay, 1775.

[4] M.M.A. Hendriksen, H.M. Huistra & H.G. Knoeff, ‘Recycling Anatomical Preparations’, in: S. Alberti and E. Hallam (eds.) Medical Museums, Royal College of Surgeons of England. (Order here) Also see Hendriksen, M. Aesthesis in Anatomy. Materiality and Elegance in the Eighteenth-Century Leiden Anatomical Collections. PhD thesis, Leiden University, 2012.