THE FIRST LUNGFUL OF NITROUS OXIDE GAS WAS INHALED IN 1799. The subject, Humphry Davy, described the experience as “a highly pleasurable thrilling in the chest and extremities.” The substance—later called laughing gas—would go on to become a critical anesthetic for minor surgery, and it is still used for that purpose today.

But the discovery would extend beyond medicine. The early path of nitrous oxide would influence the work of poet Samuel Taylor Coleridge, set off a new kind of sideshow entertainment, and launch the career of one of the most brilliant chemists of the 19th century.

Mike Jay explores that history in a special two-part interview. Jay has written about the curious journey of nitrous oxide in his book The Atmosphere of Heaven. He has also recently written the introduction to Oh, Excellent Air Bag, a new collection of historical writings about the drug from the first 125 years of its existence.