For a medievalist like myself, it doesn’t get much better than Deborah Harkness’s A Discovery of Witches. Both the internationally bestselling trilogy and the newly adapted TV show have many of the conventions of a kickass fantasy story. There’s a 1, 500-year-old vampire, a powerful witch who can literally make it rain, and their prophesied love story. There’s the imminent threat of the end of all creatures—demons, vampires, and witches—and the ensuing battle between good and evil. And, at the heart of A Discovery of Witches is an enchanted alchemical manuscript hidden deep within Oxford University’s Bodleian Library, Ashmole 782, and the witch who was able to call it up for the first time in 500 years. That witch is a medievalist, badass feminist, and history of science professor, Dr. Diana Bishop.


The British television network SkyOne’s adaptation of the books will begin streaming in the U.S. today on Sundance Now and AMC’s Shudder. To give layfolk a sense of how dope an obscure, 15th- century alchemical manuscript can be, we’ve prepared a medievalist guide to some of its features—from the philosopher’s stone to the alchemical child and more.

Where many fantasy novels are complete works of fiction, perhaps inspired by the medieval period, but not in any way historically accurate, A Discovery of Witches combines the fantastical with the academic. Deborah Harkness, the author of the series, is a history of science professor at the University of Southern California. She wrote her doctoral thesis on the history of science and magic in Europe from 1500 to 1700—the same subject her protagonist, Dr. Diana Bishop (played by Teresa Palmer in the adaptation), is researching in Oxford’s Bodleian at the outset of A Discovery of Witches.

A general view of the Radcliffe Camera building, part of the Bodleian Library, in Oxford city center on February 24, 2012 in Oxford, England. Photo : Getty

Within the first few minutes of the show’s pilot episode, Diana is standing in front of a room of academics in Oxford presenting a talk on alchemy entitled Visualizing Alchemy: Allegory and Laboratory Practice in the Seventeenth Century. Soon after, she is looking at the alchemical manuscripts of 17th -century English alchemist and astronomer, Elias Ashmole, including the enigmatic Ashmole 782.


Harkness has left breadcrumbs throughout her All Souls trilogy that make the story all the much richer for the medievalist fans of the series. But for those who aren’t familiar, I wanted to invite you all in on the secret. Welcome to the strange, wonder-filled world of medieval alchemy!

The Philosopher’s Stone

Diana studies alchemy, as does Deborah Harkness. We have J.K. Rowling and Harry Potter to thank for many people at least hearing something of alchemy, specifically the philosopher’s stone. Taking it back to 1997 and the UK release of J.K. Rowling’s first book, Harry Potter and the Philosopher’s Stone (which was changed by Scholastic to the Sorcerer’s Stone for the U.S. release), Voldemort seeks the Philosopher’s Stone to graduate from the back of Professor Quirrell’s head. In alchemy, the Philosopher’s Stone was believed to possess the ability to transform base metals into the gold. The mythical stone was considered to be a purifying agent, and thus could purify the human body to achieve life everlasting. (Or, you know, give Voldemort legs.)

Alchemist Michael Maier’s (1568-1622) depiction of the Philosopher’s Stone, emblem #21 in Atalanta Fugiens Image : Wikimedia

But, in alchemy, there are no simple definitions. Just as Diana explains in her Visualizing Alchemy lecture at the onset of the TV show, alchemical ideas are both literal and metaphorical. The philosopher’s stone was believed by alchemists to be a real agent of transmutation (maybe not quite a stone , but a physical, literal substance) as well as the spiritual transmutation of the mind from baseness to enlightenment and divinity.

The Androgyne. Miniature from Aurora consurgens, mid 15th century. Zurich, Zentralbibliothek Screenshot : Astrology, Magic, and Alchemy in Art ( Matilde Battistini


It was understood to be the combination of all of the elements of Earth, Air, Water, and Fire, of the female and the male, of all things into one unified whole—a symbol of the interconnectedness of all things. (In some ways, our medieval predecessors grasped that gender exists on a spectrum, but the alchemist friends often used the distinction of male and female as opposites, in a reductive interpretation of gender. In alchemy, certain substances are prescribed a “male” or “female” attribute.)

In simplest terms, alchemy is the study of transformation, be those transformations spiritual or material. To early alchemists, especially during the medieval period, there weren’t the strict divisions between science and religion that there are today. Alchemists had their own mythologies, their own symbols, their own spiritual system to understand the world around them that drew on everything from the Egyptian god Thoth to modern conceptions of the periodic table and medieval Christianity to early chemistry experiments. Alchemists reduced the world into elements and were fascinated by opposites, and the union of those opposites, like in the androgyne, an alchemical depiction of a being embodying the union of female and male, light and dark.

A Quick Story of Alchemy

Alchemy has roots in ancient India, China, as well as ancient Egypt. The Egyptians likely gained an understanding of alchemical processes in mummifying bodies. In fact, the word alchemy (and chemistry too for that matter) can be traced to the Egyptian word khem, which referred to the annual flooding of the Nile. It was the Greco-Egyptian alchemist Zosimus of Panopolis, who wrote the oldest, preserved alchemical texts around 300 CE where he writes about the transmutation of metals, his different instruments, and even his careful observations of how two substances can transform into something entirely new (a basic principle of chemistry to this day).

A 15th century European portrait of “Geber” (Codici Ashburnhamiani 1166, Biblioteca Medicea Laurenziana, Florence) Image : Science, Hokkaido University

Following Alexander’s conquest of Egypt, Greek philosophers borrowed from the Egyptians and began to hone their skills as alchemists, incorporating Aristotle’s ideas of the natural world, specifically Aristotle’s understanding of the four elements of Earth, Air, Water, and Fire and their properties. After the Arabs took control of Egypt, Greek texts were translated to Arabic paving the way for Arab alchemists. In the eighth century, Arab alchemist Jabir ibn Hayyan (or Geber) became the first alchemist to mention important compounds like silver nitrate, red oxide of mercury (mercuric oxide), and corrosive sublimate (mercuric chloride). In fact, (Breadcrumb #1) there’s a “Gerbert” in A Discovery of Witches, which is perhaps a small nod to this early Arab alchemist.


Alchemy came to prominence in Medieval Europe as Arab alchemical texts were translated into Latin in Spain and Southern Italy. The devastation of the bubonic plague in Europe perhaps spurred on the need for a deeper understanding of the natural world and the human body. Unfortunately for many medieval alchemists, their contemporaries didn’t always understand their experiments, and many found themselves fleeing persecution. With complex illusions to Egyptian, Greek, and Arabic myths and symbols, alchemists were conflated with sorcery and magic, and often still are today. It was an association not altogether unfounded as they danced between the physical and the metaphysical.

Alchemical Diana

In both the books and now the TV show, it is this dance between science and magic that draws Diana to the study of alchemy. After the death of her witch parents, Diana shuns all things magical, refusing to practice or hone her powers. Strangely enough, this is what also brings her to alchemy. She looks to alchemy to see how humanity could turn away from a world with magic to a world of science.

Some 17th and 18th c entury alchemical equipment is shown below: 1 aludel, for condensing vapors; 2 “Moor’s Head” still; 3 clay vessel; 4 alembic, for distilling; 5 retort; 6 bronze mortar; 7 crucible. Image : Ralph E. Lapp Life Science Library: Matter New York: Time Incorporated, 1965 ( Robinson Library

Medieval alchemy in many ways marks a transition into a new, more method-based science. Alchemists were not kitchen witches. They had specific instruments. There was the aludel (1) for condensing vapors, the alembic (4) for distilling. Alchemists developed a precise way to keep an oven set to the same exact temperature over the course of months. But, alchemists always retained their spiritual and esoteric roots.

Magic cannot be untangled from alchemy, and this is something Diana comes to learn through the course of the novels as she learns to embrace her magic. If you’re counted amongst the medievalist fans of the series, then you knew that there was no escaping magic for our protagonist. Her name alone destined her for greatness.


The well-breasted Alchemical figure of the Furnace of the Great Mother, associated with the goddess Diana. Frontispiece from Urban Hjärne, Actorum Chemicorum Holmensium, 1712. Image : Johannes Fabricius, Alchemy ( London: Diamond Books, 1994

To the ancient Romans, Diana (or Artemis for the Greeks) was the female huntress who personified the light of the moon. She was associated with the order of the natural world. Her twin brother was Apollo, who was the Greek and Roman sun God, the god of music and creativity.

To alchemists, Diana represented the Great Mother in Alchemy, the natural world from which all observations are made. Alchemical Diana is the beginning and the end, the representation of all that can be observed. Also, her twin brother, Apollo, represents the need for opposites. It’s the balance of Apollo and Diana that mirrors the alchemical understanding of the duality between dark and light, the moon and the sun.

Elias Ashmole

In A Discovery of Witches, Diana’s journey back to magic begins when she calls up the enchanted Ashmole 782 manuscript from the bowels of Oxford’s Bodleian Library. It’s a very ordinary scene for many medievalists—calling up manuscripts to look at in the reading room. But Ashmole 782 is no ordinary medieval manuscript. First off, it contains the origins of vampires, witches, and demons. The words on the pages have developed a strange habit of moving. And, if you haven’t guessed already, Ashmole 782 is not real, unfortunately.

John Riley (1646–91) Elias Ashmole c.1681–82 Oil on canvas, Presented by Elias Ashmole, 1683 Image : Ashmolean Library


That said, the Ashmole manuscripts are very real. They’re named for the alchemist, astronomer, antiquarian, government official, botanist, and collector Elias Ashmole. Ashmole was born in 1617 in Breadmarket Street, Lichfield, Staffordshire to a once-wealthy, but still-prominent family. He lived a life at the intersection of modern science and alchemy. Like a true alchemist, his life was one of dualities.

He was just as fascinated by the past as he was by the cutting edge of science. He made catalogs documenting the Royal coin collection as well as Oxford’s Roman coin collection. He collected natural and manmade specimens, even acquiring Powhatan’s Mantle, which belonged to Pocahontas’s father, and the stuffed body of the last dodo bird ever seen in Europe.

He was also a Freemason at a time when the Freemason s had many ties to alchemy, even sharing certain esoteric symbols. He was a known alchemist, writing one of the most important alchemical texts of the 17th century, Theatrum Chemicum Britannicum, which compiled many English alchemical writings that had been previously held in only private collections. In it, Ashmole calls alchemy “a wonderful science and secret philosophy, a singular grace and gift of the almighty” (13, Ashmole, Theatrum Chemicum Britannicum). To Ashmole and his contemporary alchemists, alchemy was the pursuit of the divine, of enlightenment, yet there was also a lot of public outcry against both the Freemasons and alchemists as Satanic and heretical, largely because people didn’t understand either. Both Freemasons and alchemists were shrouded in mystery. Ashmole was also a founder of the Royal Society, which (as its website proclaims) marked the emergence “of modern science” and a historic move away from the esoteric arts of alchemy.

God granting the knowledge of alchemy to the alchemist. Image : Theatrum Chemicum Brittannicum

Elias eventually donated all his manuscripts, antiques, and specimens (Powhatan’s Mantle and the stuffed dodo included) to Oxford on the condition that they build a museum to house the extensive collection. Opened in 1682, the Ashmolean Museum is considered by some historians to be the first truly public museum in Europe. Today, all the books and manuscripts of Ashmole’s original collection are housed in Oxford’s Bodleian Library.


And things get even more interesting from there. As I already mentioned, A Discovery of Witches’s Ashmole 782 manuscript, containing the origin stories of supernatural creatures, is (sigh) fictional. That said, Ashmole 782 does exist, or at least it did. Ashmole 782 has been missing since 1697, just like Harkness writes in the book! After a bit of digging around on the Bodleian Library’s website, I discovered William Henry Black and William Dunn Macray’s digitized 1845 catalog of the Ashmole manuscripts. The following description was the only note on the contents of the missing Ashmole 782 manuscript: “the [manuscript] can not now be found. It was thus described by [another cataloguist] in 1697… ‘Anthropologia, or a treatise containing a short Description of Man, in two parts: the first Anatomical, the second Psychological.”

Screenshot : Black and Macray’s A descriptive, analytical, and critical catalog of the manuscripts bequeathed unto the University of Oxford by Elias Ashmole : Also of some additional MSS. contributed by Kingsley, Lhuyd, Borlase and others. ( Databank.ora.ox.ac.uk

So, who knows, maybe Deborah Harkness is actually a witch and knows the true contents of the missing Ashmole manuscript— and in an attempt to secretly tell the world the truth of creatures, wrote a bestselling trilogy about the manuscript’s contents?



The Alchemical Child

When Diana opens Ashmole 782 for the first time in nearly 500 years, she comes across a depiction of the alchemical child. In alchemy, there are four stages to create the Philosopher’s Stone. The alchemical child represents the alchemical stage of conceptio, the second stage.

Screenshot : The depiction of the alchemical child from Ashmole 782 A Discovery of Witches, episode 1, 9:17


The child is an androgyne to symbolize the altogether new chemical compound that’s created. In A Discovery of Witches, it’s revealed that Diana is a “chimea,” a rare condition where her DNA possesses more than one genetic profile (Harkness 470).

Depiction of Conceptio by Johann Daniel Mylius’s Anatomi Auri, sive tyrocinium medico-chymicum, 1628 Image : p75 of Alexandra Lember’s The Heritage of Hermes: Alchemy in Contemporary British Literature

In both the show and the books, Matthew is an accomplished geneticist and ethologist, whose written papers cover everything from wolf pack behavior to genetics. Tucked away in a high-security Oxford laboratory, Matthew and his vampire colleagues test Diana’s blood in their ongoing research into why creatures have been dying out. The results tie Diana and Matthew together as medieval alchemy and cutting edge scientific research once again intersect.

The alchemical child represents the union of opposites. It also represents Diana, given her chimera genome, and also the love shared between Diana, a witch, and Matthew, a vampire. Diana and Matthew are opposites; it doesn’t really get more different than a witch and a vampire shacking up together. So, the love they share symbolizes the alchemical child, and maybe a hint at what’s to come later in the trilogy.

The Alchemical Marriage

Diana and Matthew also find one of the missing pages of Ashmole 782 that depicts another alchemical stage in creating the Philosopher’s Stone, conjunctio. Another name for conjunctio is the alchemical or sacred marriage. Before any union can produce a child, there needs to be some good ol’ bow-chicka-wow-wow, and that’s what the alchemical marriage is all about.


King and queen (f°10) — Splendor Solis [an alchemical treatise], by Salomon Trismosin, Germany, 1582 (Ms Harley 3469) Image : British Library

Just like the alchemical child is an androgyne and therefore denotes the union of opposites, the alchemical marriage is a depiction of the alchemical child’s mom and dad who (as you might’ve already guessed) are opposites.

There’s the female and male aspect of the alchemical marriage. The female is often referred to as the White Queen. She represents the element of Water and the Moon, Luna. The male is the Red King. He represents the element of Fire and the Sun, Sol. In chemical terms, the alchemical marriage is the union of philosophical sulfur (the female) and mercury (the male).

In A Discovery of Witches, Matthew is the Red King. He is a French baron after all, and also a vampire so red seems to make sense. Diana, whose namesake is the Roman Goddess of the Moon, is Luna and the female aspect of the alchemical marriage.

I Now Knight Thee a Medievalist

It’s no easy task to decipher medieval alchemy, let alone the alchemical principles hinted at in a fantasy story like A Discovery of Witches. Even for accomplished scholars like Harkness, there are still many pieces of alchemy that have been lost to time or have yet to be decoded.


Perhaps it’s that element of the unknown in alchemy that will always make space for magic. For our medieval predecessors, Matthew’s words that open each episode of A Discovery of Witches ring true—“Once the world was full of wonders, but it belongs to humans now. We creatures have all but disappeared—demons, vampires, and witches.”

To medieval alchemists, the world was indeed a place of magic, of creatures, and phenomena they couldn’t understand. Perhaps our contemporary world of science and technology could do with a touch of magic, of the unknown, of the alchemist’s quest for enlightenment.

I now knight thee, dear reader, a medievalist. May your world be full of wonder. Go forth and enjoy the U.S. premiere of Sky One’s A Discovery of Witches.

Sarah Durn is a freelance writer, actor, maker, and medievalist based in New Orleans, LA.

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