Unfortunately for Wells, he was not aware of this side effect, and neither was his audience at Harvard. So it happened that a medical breakthrough was showcased at one of the country’s leading medical schools, and no one even knew it.

And even stranger, this wasn’t the first time.

The pain-erasing effects of nitrous oxide were discovered almost a half-century earlier by a chemist named Humphrey Davy, who began his experiments with the chemical at England’s Pneumatic Institution. However, these experiments were largely performed on himself and sometimes his friends. He became so fixated on the high he felt when inhaling the gas—addicted, some would later say—that he risked his life more than once in his attempts to inhale larger and larger quantities, and even had a colleague built him a portable gas chamber so he could have access to the gas wherever and whenever he wanted.

Although Davy was clearly very impressed with nitrous oxide’s ability to seemingly stop the body from feeling pain, it seems that he never thought to promote it as an anesthetic for surgery. Instead, he promoted it as a cure for hangovers, and proceeded to perform detailed experiments—on himself, of course—to see just how many bottles of wine he could drink in a night and still have the effects “erased.”

But Davy was not alone in missing the enormous potential of nitrous oxide, despite frequent interaction with it. In the early 1830s, sulfuric ether and nitrous oxide were both used as recreational drugs. In America, the fashionable and the young found themselves at “laughing gas parties” or “ether frolics,” a popular traveling amusement.

In the 1830s and 1840s, it was not uncommon for a showman claiming to be a “professor of chemistry” to set up show in towns, villages, and cities throughout the United States with the express intent of showcasing these amazing gases and their “exhilarating features.” Of course, the most crowd-pleasing moments of the night were when the “professor” invited members of the audience to the stage to inhale the gases themselves. The sudden loss of equilibrium and inhibition would delight and shock the roaring crowds.

It was at one of these “laughing gas” demonstrations in 1844 that dentist Horace Wells realized the potential of sulfuric acid and nitrous oxide. The morning after witnessing the spectacle, he convinced a colleague to extract one of his teeth after he himself had inhaled some nitrous oxide. After the tooth was successfully removed, an elated Wells shouted out, “It is the greatest discovery ever made! I didn’t feel as much as the prick of a pin!”

But if Wells’ disastrous experience at Harvard had a bright spot, it was that he met John Collins Warren, the influential professor of surgery at the Massachusetts General Hospital.

Warren was already familiar with the idea of using nitrous oxide as an anesthetic through his acquaintanceship with Charles Thomas Jackson, “one of the most eccentric and bizarre of all personalities connected with the discovery of surgical anesthesia.”