Decoding the philosopher's egg
Handwritten recipe mentioning a Philosophers’ egg.
Philosophers’ egg, MS196

Miraculous Medicines: Cure-all Ingredients in Early Modern Recipes

II. Decoding the Philosophers’ Egg: Alchemy and its ‘Perplexed Allegories’

Recipe books contain a huge variety of remedies, instructions, and advice for everyday life, and many of the ingredients and outputs were multifunctional. We find an unusual substance that bridges the gap between medicine and alchemy: the philosophers’ egg. A cure-all for plague and poison, provider of immortality, plus a chemical wonder that transmutes elements into gold, this wonderous substance raises more questions than answers—and perhaps purposely so.

The elusive philosophers’ egg is an element-perfecting catalyst. While it's sometimes substituted for ‘stone’ or ‘mercury’/ ‘sulphur’ (hints of ingredients), the persisting attribution to the ‘philosopher’ alludes to its mystique. We find mention of ‘the philosophers or Hermes egg’ in MS196. This seventeenth-century manuscript is dedicated to the ‘Chymicke and Spagyrick Art’, written by an unknown scribe. Most likely, this entry, referencing the ‘circulatory vessells’ in which ‘the philosophers worke’ takes place, takes influence from the better-known Ripley Scroll, a fifteenth-century depiction of making the philosophers’ stone. The central figure of Hermes in the scroll, and thus likely the reference in the manuscript here too, is Hermes Trismegistus, a legendary Egyptian founder of alchemy. He is shown holding a vase (the egg) in the Ripley Scroll, within which is a series of fanciful figures that represent the creation of the stone. Shrouded in mystery and symbolism, some of these figures are still open to interpretation today.

Ripley Scroll, courtesy of the Wellcome Collection WMS 693 L0068462
Ripley Scroll, courtesy of the Wellcome Collection WMS 693 L0068462


We have the vessel, now to make the substance itself. We find a recipe for creating the philosophers’ egg— here ‘a proud medicine’— in MS447. A collection of medical miscellany started by a Lady Knebbit in about 1630-40, this curious recipe book contains different hands and even some named attributions. Including literal eggs (yolk and shell) as ingredients, this recipe also cites the inclusion of saffron and methods of heating and grinding the powdered ingredients, which is common in other recipes. However, things take a turn when instructed to add ‘4 or 5 fragments of unicornes horne’ (the scribe kindly offers an alternative if you can’t get hold of this).

Unicorn horn was indeed an accepted ingredient. Thought now to have been either narwal or rhinoceros horn, it was often traded in powdered form; interestingly, Elizabeth I took this further by using such a horn as a drinking vessel. Allegedly, unicorn horn was an excellent detector of and offset to poison—it’s no surprise, then, that the monarch wasn’t taking any chances. It’s worth noting that given its exoticism and miraculous properties, it was a highly expensive item. Made correctly using MS447’s recipe, however, and this philosophers’ egg could last you ’20 or 30 years’—perhaps worth it for a well-to-do household seeking a cure-for-all.


Handwritten instructions for making a philosophers’ egg.
Instructions for making a philosophers’ egg, MS447


The opaque and performative nature of these entries can’t be ignored. In a previous post I explored recipe manuscripts as a vehicle for the domestication of medicine in the early modern period, but this seems to do the opposite. To add to the intrigue, other recipes for the philosophers’ egg have been discovered in code. John Dee, a well-known alchemist, and his son wrote their recipe in cipher—which, fascinatingly, was cracked by a team of academics only last year. One reason for such encryption might be to protect against copycat rivals, not uncommon in alchemy as it was a practice shrouded in intrigue.


Alchemist in his laboratory by Thomas Wijck c1650, Staatliches Museum, Schwerin, Germany
Alchemist in his laboratory by Thomas Wijck c1650, Staatliches Museum, Schwerin, Germany


I feel there are additional motivations. Firstly, elitism: characteristic of the emerging period of Enlightenment, its air of learned superiority gave alchemy a haughty reputation. Ben Jonson’s The Alchemist (1610) captures a suspicious attitude from laymen towards the rising discipline:

‘[…] I’ll believe,’ says Surly, the resident sceptic,

‘That Alchemy is a pretty kind of game,

Somewhat like tricks o’ the cards, to cheat a man,

With charming.’



There is, secondly, an element of romance:


‘Are not the choicest fables of the Poets,

That were the fountains, and first springs of wisdom,

Wrapped in perplexed allegories?’

[205-7] answers Subtle, the ‘philosopher’.


Alchemy, like medicine at the time, was certainly not immune to the human tendency to embellish or distract to compensate for lack of knowledge: we find it in many manuscripts. Of course, the irony here is that Jonson’s Subtle is in fact a conman posing as an alchemist in pursuit of the philosophers’ stone. These ‘perplexed allegories’ are thus little but misdirection, and Jonson depicts the stone as a symbol of greed and power rather than enlightenment. Despite (or perhaps because of) this controversy, the mystery has continued to intrigue influential minds in history like Isaac Newton and Carl Jung, who conducted their own research into creating the miraculous substance. The entries in the books of medical recipes, MS196 and MS447 suggest it was a marvellous fancy that intrigued many more.


Jessica Reeves, volunteer



Herman, Eleanor, The Royal Art of Poison (New York, USA: St. Martin’s Press), 2018

Jonson, Ben, The Alchemist, Five Plays (Oxford, UK: OUP), 2009

Rawcliffe, Carol, Medicine & Society in Later Medieval England (Stroud, UK: Sutton), 1997

Unknown, MS196

Unknown, MS447



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