How Alchemy Paved the Way for Chemistry

People who practiced alchemy were searching for ways to (a) produce elixirs which would hopefully cure all kinds of diseases, and (b) turn base metals (like lead) into precious ones (like gold) via a yet-to-be-found substance called the philosopher's stone. "The Chinese were particularly interested in the first [search], the western Europeans in the second," emails Peter Maxwell-Stuart, who teaches history at the University of St. Andrews in Scotland.

From the first centuries C.E., China and India were practicing a form of alchemy, Maxwell-Stuart says. Europeans widely practiced alchemy during the Middle Ages (roughly 1000 C.E. until 1500) and even into the 18th century. "Its popularity waned during the 19th [century], but it survived even then and was still being practiced in the 20th century, too," he adds.

Thanks in part to beliefs that ultimately went back to Aristotle and the Greek philosophers, alchemists thought that nature was always striving to perfect itself. And since gold was the "perfect metal," in part because it doesn't rust or tarnish, it was regarded as the end-all, be-all of metals. The thinking was that "all other metals would eventually turn into gold by natural processes over a very long period of time," says Maxwell-Stuart.

So, the alchemist was seeking to speed up this natural process in the laboratory. "Given the basic assumptions of their belief systems, the alchemist's endeavors were entirely rational," he says. "Theoretically, too, alchemical experimentation might give an insight into God's intentions in creating the universe the way he did."

With their boiling cauldrons and intricate crucibles, alchemists (who were predominately but not exclusively men) exhibited a willingness to experiment, a trial-and-error mentality that explored multiple disciplines in hopes of illuminating nature's intricacies through honest scholarship and research. Alchemists tinkered with chemical process, like dyes and perfumes, and of course, also found ways to change the properties of various alloys.

One didn't attend "Alchemy University" to learn these skills. Instead, the knowledge of master alchemists was transferred to apprentices under a shroud of secrecy; because that knowledge was so powerful, alchemists wrote in obscure symbols, codes and metaphors to protect their ideas and insights.

Despite all the mystery, not all the experiments were bogus. Lawrence Principe, a chemist and science historian at Johns Hopkins University, decided to recreate a medieval alchemy experiment, one that he hoped would conjure a "philosopher's tree" made from a tiny bit of gold. (The philosopher's tree was a precursor to the philospher's stone.) He blended gold and mercury into a flask, which he then placed under warm sand in his lab. Days later, he was astonished to see that the recipe had in fact worked, generating a golden tree-like structure that would've undoubtedly drawn even more awe centuries ago.

These kinds of wonders may not have been possible if not for the work of countless alchemists of yore, who often used techniques like sublimation and distillation that would be familiar to any modern chemist.

Swiss physician Paracelsus was one famous alchemist from the 16th century. Part prophet, part metallurgist, part doctor, he became known as the world's first toxicologist, because he realized the correlation between dosage and toxicity — that poisons in small doses might be helpful to humans, while larger doses could be fatal. In his work, Paracelsus gave rise to the concept of making clinical medical diagnoses and then treating conditions with specific medicines.

In the 17th century, British inventor, philosopher and scientist Robert Boyle wished to find the secret of the philosopher's stone, which in the alchemic tradition was the most powerful force in nature. That power, he thought, was a key to the secrets of the universe. Although Boyle is best-known today for pioneering the scientific method and for the law named after him (Boyle's Law says that the volume of a gas varies inversely with pressure), he was enamored with alchemy all his life.

At the same time Boyle was hard at work, Isaac Newton, the genius who gave shape to the laws of gravity and optics, was actively involved in alchemy. For decades, he pursued alchemic secrets that he felt were perhaps even more fundamental than gravity: He hoped that in teasing out the chemical and mineral makeup of the world, scientists could perhaps find the one true essence of nature, thereby wielding immense power.

With its roots divided between philosophical, religious, mystical and scientific pursuits, alchemy eventually ran into the buzz saw of rational thinking that developed during the Age of Enlightenment. Its secretive tendencies drew suspicions from the government and the church, and its associations with the occult didn't help, either.

As such, alchemy faded into obscurity, leaving behind a reputation colored by charlatanism and quackery. It's no wonder that ancient peoples first gawped at the perceived power of alchemists, and later, as more refined scientific methods took hold, began to mock them.

But with their legitimate chemical experimentations and applications, alchemists had already made their mark, paving the way for modern chemistry.

"Experimentation almost inevitably resulted in the discovery of various substances hitherto either unknown or not understood — phosphorus is an obvious example — and so that aspect of alchemy leads into modern chemistry," says Maxwell-Stuart.