An alchemical recipe, kept secret for 400 years, hangs on a wall in the history department at Johns Hopkins University. The message is hidden in a picture of a large and muscular dragon. On a hill behind the creature, three animals tussle in mortal battle. A rooster pecks at the back of a fox, as if to eat it, while the fox is devouring another rooster.
This was an alchemist’s way of describing a chemical reaction. Understand it, and you will be able to transform gold.
Or you can simply ask Lawrence Principe to explain it to you. Principe, 55, is one of the world’s foremost experts in alchemy. After he solved the cipher of the dragon, Principe commissioned the scene in ceramic and hung it in his office, a scholarly version of a big-game trophy. A historian and a chemist, Principe pores over old treatises, then pours what he learns into antique glassware.
His work shows that alchemy should not be dismissed as cheap tricks. Principe has replicated alchemists’ ancient formulas, taking chemical reactions several steps beyond what skeptics thought possible. He has reproduced alchemists’ unusual materials, such as a glow-in-the-dark stone that remained a mystery for centuries.
Jennifer Rampling, a Princeton University historian who also specializes in alchemy, said:
“He uses practice as a way to shed light on text and text as a way to shed a light on practice”
In his chemistry lab, a short walk from the history department, the cabinets are full of alembics, retorts and other bulbous glass devices. On the counter sits a large jar labeled “Phlegm of acidified urine.” More than one alchemical recipe calls for human pee. Principe said an old Arabic text used the phrase “the secret is within you,” probably meaning: Well, reader, you go figure it out.
“But some people took that more literally,” Principe said, “so they ended up using vast amounts of urine.” Urine was cheap and surprisingly useful. It was the crucial ingredient in the discovery of the element phosphorus by Hennig Brand, a 17th-century alchemist whose preferred urine came fresh from beer drinkers.
Alchemists, even when they were mucking about with pub waste, saw their work as a way to improve upon the natural world. They wanted to create more powerful medicines and stronger building materials and, yes, turn cheap metals into gold.
The alchemical practice began about 1,500 years ago in Hellenistic Greece. It came to Europe by way of the Middle East. Like the word algebra, alchemy wears its Arabic influences in its name. Alchemy flourished in Europe between the 13th and 18th centuries. “What happens in the Middle Ages is that alchemy is celebrated — and it might be one of the first disciplines that is celebrated this way — as the power it gives to human beings to control nature,” Principe said.
By the 19th century, alchemists were branded as cheats or occultists. Or they were dismissed as crackpots, hunched over bubbling potions in smoky huts, on a quest for “the philosopher’s stone.” Harry Potter fans might recognize the stone as a minor plot point in the first book. But 400 years ago, alchemists believed that the mythological object was real, and that it would let them transmute lead into gold. (A few people still pursue the stone. “Practical alchemy is by no means dead,” Principe said. Though his preferred response to some living alchemists, he said, is to “run away.”) Until about 1700, there was no practical division between chemistry and alchemy. In his academic work, Principe refers to both under the umbrella of an old phrase, “chymistry.”