How to Make a Homunculus and Other Horrors

In researching How Frankenstein’s Monster Works (and the podcast episode), I did quite a bit of reading about the homunculus. If you’re not hip to this terminology, all you need to know is that a homunculus is an artificial humanoid created through alchemy. While not quite a human, this creature is a “rational animal” and another fictional page in humanity’s dream of mastering life and death.

The medieval text known as the Liber Vaccae or Book of the Cow lays out some rather grotesque and confusing instructions in the art of DIY homunculi brewing—and Maaike Van der Lugt‘s Abominable Mixtures: The Liber vaccae in the Medieval West, or The Dangers and Attractions of Natural Magic really lays out some excellent commentary on what it all means.

Allow me to break it all down into some quick bullet points. Be warned that this is all rather grotesque. Also, please do me the favor and don’t actually attempt this at home.

Yield: 1 blasphemy


  • magician semen
  • sun stone (a mystical phosphorescent elixir)
  • animal blood
  • a cow or ewe
  • sulfur
  • a magnet
  • green tutia (a sulphate of iron)
  • a large glass or lead vessel


  1. Mix the semen and sun stone and inseminate the cow or ewe.
  2. Carefully plug the animal’s vagina with the sun stone.
  3. Smear the animal’s genitals with the blood of another animal.
  4. Place the artificially inseminated animal inside a dark house where the sun never shines.
  5. Feed the cow or ewe exclusively on the blood of another animal.
  6. Prepares a powder of ground sun stone, sulfur, magnet and green tutia.
  7. Stir with the sap of a white willow.

At this point, the text indicates that the cow or ewe should give birth and the resulting “unformed substance” should be placed in the powder you just prepared—which will cause the amorphous blob to grow a human skin.

Next, keep the newborn homunculus in a large glass or lead container for three days. The creature will become crazy hungry in this time, so you’ll then feed it the blood of its decapitated mother for seven days. In this time, it should develop into a full-grown tiny, grotesque humanoid with some fragment of a human soul.

Now what, right? Well, as it turns out, the homunculus has many uses for a practicing medieval sorcerer:

If it is placed on a white cloth, with a mirror in its hands, and suffumigated with a mixture of human blood and other ingredients, the moon will appear to be full on the last day of the month. If it is decapitated, and its blood is given to a man to drink, the man will assume the form of a bovine or a sheep; but if he is anointed with it, he will have the form of an ape. If the homunculus is fed for forty days in a dark house, on a diet of blood and milk, and then its guts are extracted from its belly and rubbed onto someone’s hands and feet, he may walk on water or travel around the world in the winking of an eye. Kept alive for a year and then placed in a bath of milk and rainwater, it will tell things that happen far away.

Oh, and then there’s this perplexing bit about turning a decapitated cow into a swarm of bees:

The fourth experiment describes an elaborate procedure to generate bees from the corpse of a decapitated calf. This involves locking up the corpse in a dark house with fourteen closed windows on the East, blocking all its body orifices after having reattached the head, hitting it with a large dog’s penis, extracting the flesh from the skinned corpse, grinding this with a certain herb, and leaving the mixture in a corner of the house, until it will be converted into worms.

I trust you’re properly grossed out by this point, so I’ll skip to the part where I frame all of this in some sort of scientific reasoning.

As alarming and grotesque as these ideas are, they underline the mindset of the alchemist, who wandered a meandering path of chemistry, philosophy and superstitious occultism on the quest for knowledge. At the time, it was widely believed that humans could mimic and manipulate natural reproductive processes—especially when it came to simpler organisms such as bees.  And it was still an age in which spontaneous generation seemed a sensible explanation for maggots in your meat.

The ideas are crazy to a modern reader, but they underline what our ancestors thought was possible. And as we continue to venture into an age of genetic manipulation and human cloning, who’s to say they were wrong?

But again, don’t try this at home.

So there you have it! You can find the Stuff to Blow Your Mind podcast on iTunes, Zune and the RSS feed. And don’t forget the free HowStuffWorks App!

Image source: Alexandre Dulaunoy/Creative Commons

Originally published at HSW: How to Make a Homunculus and Other Horrors

Robert Lamb is a senior staff writer at and co-host of the Stuff to Blow Your Mind podcast and blog. He is also a regular contributor to Discovery News. Follow him on Twitter @blowthemind.


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