How to correct Plato, alchemically?

By Bojidar Dimitrov, AlchemEast Project

Jabir Ibn Hayyan is a figure of key importance for the development of alchemy and chemistry. A vast body of literature virtually covering the entire spectrum of ancient science has been attributed to the Islamic polymath, and yet much of the little we know about him remains shrouded in mystery. The very historicity of Jabir’s person and the authenticity of his works have been the subject of rigorous scholarly debate. This is largely due to the fact that the majority of the texts which belong to the Jabirian corpus have not been edited and published.

The scant biographical data provided by mediaeval Islamic sources and Jabir’s own works suggests that his lifetime spanned the period between ca. 721/725 and 812/815 AD. The so-called Jabir Problem mainly revolves around different aspects of this alleged historical context. The ambiguous relationship between the Arabic Jabirian corpus and the nascent alchemical tradition of the Latin West is the other major side of the conundrum. 

Paul Kraus’ ground-breaking studies on Jabir[1] proposed that the Jabirian corpus was probably compiled over a longer period of time by a school of alchemists who circulated their works under Jabir’s name. Similar doubts were already expressed by mediaeval Islamic scholars, and Kraus’ detailed analysis of the language and the content of seminal texts argues that the scientific terminology, doctrines and references to Greek authorities found in them point to a later stage of Islamic intellectual history, which began in the ninth century. Kraus’ conclusions have been debated by scholars since their publication in the 1940s, but the scope and depth of his research remain unmatched to this day.

One of the current objectives of the AlchemEast Project is to make available a collection of alchemical recipes belonging to a sub-genre of Jabir’s corpus. Plato’s Rectifications is the only surviving collection of a cycle of pseudepigraphical ‘rectifications’ associated with ancient authorities. The work is presented as a commentary on alchemical doctrines ascribed to Plato that the Greek sage is said to reveal to his disciple, Timaeus. The ninety recipes involve alchemical procedures with mercury which are intended to illustrate the application of Plato’s theories.

Socrates discussing philosophy with his disciples (from a thirteenth-century Arabic manuscript).

Jabir’s attribution of alchemical material to Plato is pertinent to the reception of Platonic influences in Islamic alchemy and the wider context of Islamic thought. While Jabir’s system incorporates key Neoplatonic traits of Greek philosophical alchemy, its experimental and arithmological developments are highly original and do not seem to derive from extant Greek texts. Furthermore, no alchemical texts are attributed to Plato (or Socrates) in the Greek tradition.[2] There are, however, Syriac recipes attributed to Plato, and he is generally accorded a prominent place in Arabic occult literature. Such facts may indicate that Jabir could have been influenced by late antique Neoplatonic traditions of a distinctly Near Eastern flavour.

An excerpt from Rectification Nr. 14 presents a recipe which involves the heating and cooling of mercury:

Then he said: take ten measures of spirit (i.e. mercury), put it in the middle gourd (i.e. glass vessel), and tighten upon it the alembic which has no aperture (i.e. valve). Heat it over gentle fire for ten days, then cool it off on the eleventh. Repeat the operation and gather the first water. The gourd containing mercury will be heated, or joined to the other gourd until it (i.e. mercury) dissolves in one of the two gourds. Take the thickened [residue], put it in the second gourd, and heat it until it melts, becomes liquid and turns red. Then heat the water until it boils and [the condensate] starts dripping all over the residue, [so that] it swells, absorbs some of the water and is incerated by it, and yields. It will become like wax, just as we described initially, and [even] better. If the procedure starts by heating the water until [the condensate] drips over the residue, it will be dissolved, and both will be dissolved, coagulated and incerated together, [and thus the procedure] is also complete. Peace.

Image 2: Depiction of alchemical apparatus with an alembic (MS, BNF Arabe 6915)

Depiction of alchemical apparatus with an alembic (MS BNF Arabe 6915).

The text exemplifies the fluidity of content that alchemical recipes often exhibit. The procedures it describes are relatively simple, but the textual variants in the manuscripts allow different possibilities. The translation above is not conclusive, since the relationship of the alembic and the two vessels is somewhat ambiguous. According to certain readings, for instance, the second vessel and the alembic must be alternated during the process of dissolution. The examination of further textual variants and manuscripts can expand our understanding of Jabir’s technical methodology. Ultimately, the intertextuality of Platonic pseudepigrapha found in Jabir and other traditions calls for an overarching discussion of Plato’s role in alchemical discourse. Whether this role was itself rectified by practitioners over the centuries, or the fluctuations we encounter in manuscripts are of a purely textual nature, are the main questions AlchemEast aims to address.


[1] Paul Kraus, Jābir ibn Ḥayyān. Contribution à l’histoire des idées scientifiques dans l’Islam, Vol. II. Jābir et la science grecque (Cairo: Mémoires de l’Institut d’Égypte 45.1, 1942).

[2] Ibid., p. 58.

Sloane Family Recipes

By Lisa Smith

The famous eighteenth-century physician, Sir Hans Sloane, occasionally pops up in the pages of The Recipes Project, with patients keeping recipes or Sloane collecting manuscript recipe books. And, although the Sloane family had an illustrious physician and collector in their midst, they collected medical recipes like many other early modern families. Three Sloane-related recipe books that I’ve located so far provide insight into the family’s domestic medical practices and emotional lives.


Elizabeth Fuller: Collection of cookery and medical receipts
Credit: Wellcome Collection, London.

Two books are held at the British Library, donated in 1875 by the Earl of Cadogan. A book of household recipes, primarily for cookery, was owned by Elizabeth Sloane—Sloane’s daughter who married into the Cadogan family in 1717 (BL Add. MS 29739). The second book, c. 1750, contained medical, household and veterinary recipes (BL Add. MS 29740), including several attributed to Sir Hans Sloane. A third book, which belonged to Elizabeth Fuller, is held at the Wellcome Library (MS 2450) and is dated 1712 and 1820. Given the initial date and name, it is likely that the book’s first owner was Sloane’s step-daughter from Jamaica, Elizabeth Rose, who married John Fuller in 1703. Sloane’s nephew, William, married into the Fuller family as well in 1733.

Elizabeth Sloane, of course, compiled her collection long before her marriage; born in 1695, she was sixteen when she signed and dated the book on October 15, 1711. This was a common practice for young women who were learning useful housewifery skills. The handwriting in the book is particularly good, with lots of blank space left for new recipes, suggesting that this was a good copy book rather than one for testing recipes. There are, even so, some indications of use: a black ‘x’ beside recipes such as “to candy cowslips or flowers or greens” (f. 59), “for burnt almonds” (f. 57v) or “ice cream” (f. 56). The ‘x’ was a positive sign, as compilers tended to cross out recipes deemed useless.

The Cadogan family’s book of medicinal remedies appears to have been intended as a good copy, but became a working copy. In particular, the recipes to Sloane are written in the clearest hand in the text and appear to have been written first. Although there are several blank folios, there are also multiple hands, suggesting long term use. There are no textual indications of use, but several recipes on paper have been inserted into the text: useful enough to try, but not proven sufficiently to write in the book. As Elaine Leong argues, recipes were often circulated on bits of paper and stuck into recipe books for later, but entering a recipe into the family book solidified its importance—and that of the recipe donor—to the family.

Sloane’s recipes are the focal point of the Cadogan medical collection. Many of his remedies are homely, intended for a family’s everyday problems: shortness of breath, itch, jaundice, chin-cough, loose bowels, measles and worms. There are, however, two that spoke to his well-known expertise: a decoction of the [peruvian] bark (f. 8v)—something he often prescribed–and “directions for ye management of patients in the small-pox” (f. 10v).

Elizabeth Fuller compiled her book of medicinal and cookery recipes several years after her marriage and the book continued to be used by the family well into the nineteenth century. The book is written mostly in one hand, but there are several later additions, comments and changes in other hands. The recipes are  idiosyncractic and reflect the family’s particular interests: occasionally surprising ailments (such as leprosy) and a disproportionate number of remedies for stomach problems (flux, biliousness, and bowels). The family’s Jamaican connections also emerge with, for example, a West Indies remedy for gripes in horses (f. 23). There are no remedies included from Sloane, but there were several from other physicians.

This group of recipe books connected to the Sloane Family all show indications of use and, in particular, the Cadogan medical recipe collection and the Fuller book suggest that they were used by the family over a long period of time. Not surprisingly, the Fuller family drew some of their knowledge from their social and intellectual networks abroad.

But it is the presence or absence of Sloane’s remedies in the books that is most intriguing. Did this reflect a distant relationship between Sloane and his step-daughter? Hard to say, but it’s worth noting that his other step-daughter, Anne Isted (and her husband), consulted him for medical problems and the Fuller family often wrote to him about medical education, books, and curiosities.

Or, perhaps, it highlights the emotional significance of collecting recipes discussed by Montserrat Cabré. Sloane was ninety-years old when the Cadogan family compiled their medical collection.

Hans Sloane Memorial Inscription, Chelsea, London. Credit: Alethe, Wikimedia Commons, 2009.

It must have been a bittersweet moment as Elizabeth Cadogan (presumably) selected what recipes would help her family to remember her father after he died: not just his most treasured and useful remedies, but ones that evoked memories of family illnesses and recoveries.

An earlier version of this post was published at The Sloane Letters Project.

But does it work? Playful magic and the question of a recipe’s purpose

By Melissa Reynolds

An early sixteenth-century recipe for “good gome” in Wellcome Library MS 406, f. 23r. Digitized images of the manuscript available at https://wellcomelibrary.org/item/b18935709.

One of the many pleasures of studying late medieval English “how-to” manuscripts is the wide and often surprising array of knowledge to be found within them. Most contain a good bit of medical information, such as herbal recipes and instructions for bloodletting, and many also contain useful household information, like directives for animal husbandry, fishing, hunting, sewing, ink-making, and so on. Also common to these collections are charms for curing fevers, staunching blood, and protecting women in childbirth. Some medieval English collections of recipes also contain magic of a lighter sort, like directions to “make a woman lift her skirts” or “to make thunder and lightning,” discussed in earlier posts by Laura Mitchell and Catherine Rider.

One such example of a light—and somewhat lascivious—recipe is found on folio 20 of Bodleian Library MS Ashmole 1389, a late fifteenth-century recipe collection compiled by William Aderston, probably a surgeon working in London.[1]

To make men & women to take off their clothes

Take grain with evil thistles [thystylls] which grow above the ditch & make from that a powder & put it in someone’s lap & immediately he or she will take off his or her clothes.[2]

Image credit: British Library, from Prudence Guilllaume de Roujoux, Histoire d’Angleterre (Paris, 1844), text added by Melissa Reynolds.

Certainly, as Mitchell has suggested, recipes like this one “to make men and women take off their clothes” are inherently playful. Yet I am also inclined to agree with Rider who points out that there is little evidence that medieval compilers drew a sharp distinction between lighthearted recipes and straightforwardly practical ones. In the case of Ashmole 1389, the recipe to make men and women shed their clothes appears within a short section of non-medical recipes in an otherwise overwhelmingly medical collection. Most other non-medical entries in the manuscript are clearly useful, like a recipe to make glue or instructions for fishing and engraving on metal.

So why was this recipe included in an otherwise useful collection, and what can its inclusion teach us about late medieval culture?

Historians can read 500 year-old recipes for medicine, agriculture, textile production, or cooking and understand why such knowledge was selected for “how-to” manuscript collections, even though the materials and techniques described are unfamiliar to us now. We can understand why so many collections feature useful, natural magic, as there was little distinction between magical and non-magical cures in medieval culture. In these cases, our understanding of the medieval recipe book rests on the basic premise that people wanted acces to useful (and useable) knowledge.

But recipes like this one “to make men and women take off their clothes” are perhaps more illuminating precisely because they don’t fit this mold. They challenge our presumptions about the purpose and function of a recipe. This recipe isn’t obviously practical, nor is it even apparent that it could be, or ever was, attempted by its compiler.

Though lighthearted magic like that in Ashmole 1389 is not nearly as common as healing magic, its presence in medieval collections should encourage us to reflect on what we expect from a recipe, and how those expectations color our historical interpretation. Perhaps we should ask ourselves if our focus on finding out how pre-modern recipes “work” always reflects the focus of pre-modern compilers and readers? Attempts at recipe reproduction can yield unmatched insights into pre-modern worldviews, materials, and techniques; hands-on and collaborative research into recipes should by all means continue! But while we’re building furnaces, making chacolet, and casting flowers, let us also remember that a pre-modern recipe might have had any number of meanings or uses for the pre-modern reader, some of which we may not yet fully understand.


[1]Aderston left his signature at the bottom of a recipe on folio 14v (“per me W. Aderston”) and a record at the National Archives of the UK contains reference to a “William Aderston, of London, surgeon” as plaintiff in a trespassing case against the sheriffs of London sometime between 1483–1515.

[2]Ad faciendum homines & mulieres deponere pannos suos / Accipe grana malignos cardenibus ^thys tylls^ qui crescunt super fossat & fac inde pulvere & ponite in gremio alicuius & statim exuet pannos. The Latin gremio could be “lap, bosom” or “womb; female genital parts.” You can see how a different translation would change the sense of the recipe entirely.


True Colors, or the Revelatory Nature of Cold

By Thijs Hagendijk

Heat is transformative, brings about change, separates substances or bring them together. Every student of chemistry knows how to enable or enhance a chemical reaction by applying energy to a system, usually in the form of heat. Early modern practitioners did not think otherwise. Fire was the transformative element and key to the production of all kinds of different materials, ranging from the philosopher’s stone to artisanal products such as glass, porcelain or pigments. Applying heat to bring about change is publicly ingrained thermodynamics, but one thing is even more obvious. Once heated, things have to cool down again.

Figure 1: Eikelenberg’s notes on the art of painting, comprising five different manuscripts. Photograph: Regionaal Archief Alkmaar.

When the request came to write a blogpost on cold and recipes, I was somewhat hesitant. Heat seems to elicit the most interesting stories and anecdotes, but interesting cases with respect to cold failed to come to mind immediately. Hence, I tried a different approach and looked at how cold featured in a collection of overtly practical notes on the preparation of paint materials collected by the Dutch polymath and painter Simon Eikelenberg (1663-1738). Intended for publication, he promised his readers an “accurate descriptions of the origin of making, preparation and general use of paint materials, oils, mix-fluids and varnishes.”[1]  It was within the confines of this manuscript that I began to discern two themes with respect to cold in practices of making.

Figure 2: Reconstruction of one of Eikelenberg’s varnish recipes. The varnish was prepared in a glazed pot, placed in a sand bath and heated on fire. Photograph: Thijs Hagendijk.

It is only when things have cooled down that the transformative work of heat can really be judged. Eikelenberg describes for instance how he experimented with minium, a red lead-based pigment, which he heated in a crucible and placed in a fire. “The more it glowed, the more the minium turned yellow near the sides of the crucible, the lowest parts alike; which, when it was cold, appeared to be nothing else but yellow massicot.” [2] Eikelenberg also describes the preparation of various varnishes. Here too, quality and properties of substances are explicitly observed after the varnishes have cooled down. “When the varnish was cold I found that it was rather thin and that it did not cover well.” [3]  Another varnish was prepared on a hot sand bath, after which Eikelenberg “filtered it through a cloth and let it cool: it appeared then as a thickish and yellowish varnish.” [4]  Pay attention to the word “then”: there is a clear order of things that speaks through Eikelenberg’s notes. Being cold is a condition that precedes testing and Eikelenberg makes that rather explicit.

Figure 3: It is hard to achieve a homogeneous mixture when preparing varnishes. A whitish sediment is developing in this varnish, which is in coherence with Eikelenberg’s notes. Photograph: Thijs Hagendijk.

Whereas heat is transformative, it is only in the absence of heat that things can be trusted to stay the same. Continuing with the varnishes, Eikelenberg was well aware that their preparation does not stop after the ingredients have been heated and combined. As long as it is still hot, the apparently homogeneous concoction can easily coagulate and fall apart. Eikelenberg wrote in his notes: “We can conclude that to prevent curdling it is necessary not to stop stirring before the mixture is cold.” [5] Indeed, each time he made varnishes, Eikelenberg made sure to keep stirring until everything was cooled down: “stirring steadily until all was cold” or “having stirred until it became cold”.[6]

Figure 4: Eikelenberg mentions that: “[w]e can conclude that to prevent curdling it is necessary not to stop stirring before the mixture is cold.” Passage marked in red. Photograph: Regionaal Archief Alkmaar.

For Eikelenberg, heat was both friend and foe and until his varnishes reached firm, cool ground, they required careful guidance and attention. Cooling down was thus as arduous a process as heating the mixture was in the first place. Yet, once cooled down, true colors are revealed – deprived from heat and stabilized by the cold.

[1] Simon Eikelenberg, “Aantekeningen betreffende schilderen,” MS 391, Collectie Aanwinsten, Regionaal Archief Alkmaar: fol. 1. “Naukeurige beschrijving van de oorsprong of making, bereiding en ’t algemeen gebruik der verfstoffen, olijen, mengvogten en vernissen.”
[2] Simon Eikelenberg, “Aantekeningen betreffende schilderen,” MS 390, Collectie Aanwinsten, Regionaal Archief Alkmaar, fol. 806. Original: “na mate dat het gloejend wierd, veranderde de menij die naast tegen de zijden van de kroes aan-zat en wierd geel, gelyk ook ’t onderdtste; ‘t welk doe ‘t kout was niet anders dan gele masticot geleek”.
[3] Eikelenberg, “Aantekeningen betreffende schilderen,” MS 390, fol. 827. Original: “Doe de vernis koud was bevond ik ze wat dun en datze niet genoeg dekte.” Translation from: A. van Schendel, “Simon Eikelenberg’s Experiments on the Preparation of Varnishes,” Studies in Conservation 3 (1958), 130.
[4] Eikelenberg, “Aantekeningen betreffende schilderen,” MS 390, fol. 802. Original: “Doe ‘t wel vermengt was, kleijnsde ik ‘t door een doek en liet het kout worden, wanneer ‘tzelve een dikagtige en geelagtige vernis vertoonde” Translation from: Schendel, “Simon Eikelenberg’s Experiments,” 128.
[5] Eikelenberg, “Aantekeningen betreffende schilderen,” MS 390, fol. 824. Original: “Hieruijt kan men afnemen dat om ’t schiften voor te komen, men niet moet op-houden met roeren voordat se kout is.” Translation from: Schendel, “Simon Eikelenberg’s Experiments,” 129.
[6] Eikelenberg, “Aantekeningen betreffende schilderen,” MS 390, fol. 827. Original: “gestadig omroerende totdat het gantschelijk koud was.” Translation from: Schendel, “Simon Eikelenberg’s Experiments,” 130. Eikelenberg, “Aantekeningen betreffende schilderen,” MS 390, fol. 832. Original: “tot koutwordens toe geroert te hebben”.