By Érika Wicky
If the decorative arts of the eighteenth century shine so brightly, it is thanks to the innovation and mastering of techniques such as gilding and varnishing.[i] While the latter may have given surfaces the shiny appearance that was particularly desirable at the time, both were above all essential to protect wood, especially against insects. Varnishes were used not only for furniture, but also for small painted objects such as snuffboxes, fans, and boîtes à mouches or fly boxes (Fig. 1). Varnishes’ appealing visual characteristics and protective properties were marred, however, by what was generally perceived as their unpleasant smell. The recipes for some of these varnishes have been passed down to us, and with them, the possibility to retrieve their odors. Some of these recipes continue to be in use, such as the varnish described by French cabinetmaker André-Jacob Roubo in L’Art du menuisier-ébéniste in 1774 (Fig. 2), whose use remains frequent in restoration[ii] so that the same recipe is regularly remade at the Center for Research and Restoration of Museums of France. While current olfactory accounts of these products are much more nuanced, they do persist, which is a sign that olfactory sensitivity has certainly evolved, but also that the smell of the varnish remains a major part of the experience of its manufacture and use. What are the substances that have given varnishes such a characteristic olfactive identity through the centuries? And how has the meaning attributed to these smells evolved?
There are a number of recipes for varnishes found in eighteenth-century texts, and all essentially contain aromatic plant resins. For instance, the varnish used by Jean Félix Watin (1773) was prepared as follows: “Two ounces of mastic in tears and half a pound of sandarac in a pint of wine spirit, when the materials are well dissolved together, incorporate four ounces of Venice turpentine.”[iii] Similarly, Roubo’s (1774) was “composed of one pint or two pounds of wine spirit, five ounces of sandarac, two ounces of mastic in tears, one ounce of gum elemi and one ounce of oil of aspic.”[iv] Essentially, the process involved Venice turpentine (the name given to the resin of Melese[v]), mastic in tears, sandarac and other more precious resins such as copal, or of lesser quality such as galipot, which were generally dissolved in alcohol (wine spirit), and then heated. This gave off such a strong and unpleasant odor that the practice was forbidden within city walls.[vi] Indeed, this smell could be significant during the process of preparation, and Jean Riffault, for example, recommended that cooking copal should be stopped when it gave off an empyreumatic or burnt smell [vii] (Fig. 3).
Although the smell of varnish released during firing is still considered strong and dangerous today, our current perceptions seem to accord less significance overall to the smell of varnishes. For example, the sensory-aware description of a varnish recreation at the V&A mentions that the smell of lavender dominated that of turpentine.[viii] That the smell of turpentine could be camouflaged was well known in the eighteenth century, when aspic oil was often adulterated with turpentine, which was much less expensive. To ensure the quality of the aspic oil, Watin recommended approaching a soaked cloth to a fire, which dissipates the lavender oil quickly and allows the detection of the odor of any turpentine that may have been added.[ix] Since most of these raw materials were subject to adulteration, the artisans could, in fact, evaluate their quality thanks to their sense of smell. For example, according to Baudeau’s Encyclopédie méthodique (1783-4), an unpleasant smell from gum elemi (which is usually pleasant) can reveal that it was substituted with galipot.[x] The olfactory consensus here seems to rest on the fact that the artisan knew enough about the agreeable smell of gum elemi not to be tricked. Similarly, olfactory references in professional treatises, such as Roret’s guide, often rely on experience, invoking “characteristic” or “particular” odors rather than defining them by analogy, like when elemi gum is described as smelling like fennel.[xi]
Far from being a mere nuisance, the smell of the raw materials thus made it possible to identify them, in the same way that wood, whose different species were characterized by their smell, was sometimes considered when choosing materials. Odour could be so defining that, as Cheng He has shown, the concept of lacquer was long associated with a range of odorous resins rather than with a finished object.[xii] For example, objects decorated with Martin varnish [xiii] were simultaneously prized in the eighteenth century and dreaded for their bad odor. They were distinguished in particular by the use of copal, a plant resin whose use as an incense in Mexico is often mentioned in technical treatises.[xiv]
The manufacture of varnishes thus intersects with other types of olfactory knowledge. The resins used for the varnishes are found in many other recipes, in particular for perfumes. Louis Peyron’s 1986 compilation of recipes for perfumes to be burned, which had been recommended as a way to defeat the plague in the 1720s, reveals that the components of varnishes were all found in these recipes and that their strong odor was believed to have the prophylactic virtue of keeping miasmas away.[xv] The connection between varnish and perfume can be further explored in eighteenth-century perfumery treatises: in 1761, the royal perfumer proposed a “varnish” for the complexion made with sandarac spirit, whose protective and preserving virtues aligned with those of wood varnishes.[xvi]
The negative connotations associated with the smell of varnish seem to have faded with time; tear mastic was used in perfumery into the nineteenth century, [xvii] while, according to perfumer Lucille Lefranc Gallo, gum elemi is now experiencing renewed interest in perfumery, alongside a range of spicy raw materials. The scent of varnishes produced according to eighteenth-century recipes, such as Roubo’s or Watin’s, takes us back to a time when smells had specific connotations and were part of a network of knowledge provided by olfaction, particularly with regard to the identification of materials. It is not only the sensitivity that has evolved, but also the entire olfactory culture.
[i] My warm thanks to Marc-André Paulin (C2RMF), Lucille Lefranc Gallo and Ersy Contogouris for their advice and comments. This text forms part of the work conducted for the Marie Sklodowska-Curie research project PaintOdor (845788).
[ii] Nathalie Balcar, Frédéric Leblanc et Marc-André Paulin, “La protection de surface pour les meubles en marqueterie de métal du musée du Louvre : étude d’un vernis, entre formulations anciennes et expérimentations actuelles,” Technè, 49 (2020).
[iii] Jean Félix Watin, L’art du peintre, doreur, vernisseur (Paris: 1773), 229. Watin claimed to have discovered the secret of an odorless varnish, but he does not give its recipe in his book.
[iv] André J. Roubo, L’Art du menuisier-ébéniste (Paris: 1774).
[v] Pierre Chomel, Abrégé de l’histoire des plantes usuelles (Paris: 1712), 190.
[vi] Watin, 224.
[vii] Jean Riffault, Manuel théorique et pratique du peintre en bâtimens, du doreur et du vernisseur (Paris: Roret, 1825), 254.
[viii] “This time, despite both ingredients being very strong smelling, the scent of the lavender oil completely overpowered that of the turpentine.” Simona Valeriani, “Recreating Sixteenth-Century Varnishes on the History of Design Course,” June 23, 2017, https://www.vam.ac.uk/blog/projects/recreating-sixteenth-century-varnishes-on-the-history-of-design-course.
[ix] Watin, 202.
[x] Nicolas Baudeau, Encyclopédie méthodique (Liège: 1783-1784), 63.
[xi] Riffault, 229.
[xii] Cheng He, “Understanding the Fragrance of Lacquer in Early Modern Europe,” University of Toronto Art Journal 9.1 (2021): 68-76. https://utaj.library.utoronto.ca/index.php/utaj/article/view/36618
[xiii] Anne-Solenn Le Hô, Céline Daher, Ludovic Bellot-Gurlet, Yannick Vandenberghe, Jean Bleton, Myrtho Bonnin, Léa Drieu, Juliette Langlois, Céline Paris, Marc-André Paulin, “French lacquers of the 18th century and vernis Martin,” ICOM-CC 17th Triennial Conference, September 2014, Melbourne, Australia. hal-01279161
[xiv] Chomel, 512.
[xv] Louis Peyron, Odeurs, Parfums et parfumeurs lors des grandes épidémies méridionales de peste Arles 1721, Talk presented at the Arles Académie on March 23, 1986.
[xvi] Le parfumeur royal (Paris: 1761), 115.
[xvii] Auguste Debay, Nouveau manuel du parfumeur-chimiste (Paris: E Dentu, 1856), 37.