This summer, I conducted a series of backyard experiments involving gunpowder and spirits. For each trial, I poured old-fashioned black gunpowder onto a plate, dampened it with a bit of rum or gin or some other liquor, and then applied a flame. Sometimes this resulted in a satisfying flash, followed by a small cloud of acrid smoke. Other times, nothing.
The experiments were a little bit of chemistry, and a lot of history. Centuries ago, British sailors supposedly used gunpowder to determine whether their daily tot had been watered down by an unscrupulous purser. Pursers were widely assumed to requisition a portion of official rum supplies for personal use, and to top up the casks with water. Sailors believed that gunpowder splashed with watered-down liquor wouldn’t combust, while liquor containing more than 50 percent alcohol by weight would cause the powder to flare. If it did flare, the liquor was “proved,” giving rise to the term proof. If it didn’t, the purser might find himself tossed overboard. This was known as the “gunpowder proof test,” and I was curious if it would actually work.
In my home tests, the results were inconsistent and wholly mystifying. I learned that Lemon Hart 151-proof rum (75.5 percent alcohol) would always flare, but other spirits, including Plymouth Navy Strength Gin (57 percent), ignited only occasionally. At times, even liqueurs, with considerably lower proofs, would unexpectedly blaze up. The inconsistency may have resulted from the humidity on the days I tested. It may have had to do with my efforts at quality control, which involved an occasional nip of the test product. But it made me wonder if pursers had been unjustly given the heave-ho in humid environments, or if the gunpowder test was possibly spurious altogether. One vendor of black powder I spoke with speculated that the practice might have had a scientific basis—something to do with the potassium nitrates in the gunpowder being soluble in water but not in alcohol. My research will continue as long as I have musket powder and fingers.
The proof test may actually be part of a larger maritime tradition of mixing gunpowder and liquor. Robert Lee, a biographer of Edward “Blackbeard” Teach, reported that the notorious pirate once got the attention of his compatriots in a tavern by “mixing gunpowder in his rum, setting it on fire and guzzling the explosive mixture.” How this was accomplished by someone as famously bearded as Teach was not adequately explained, and I didn’t feel an immediate need to reenact this feat.
Then I heard about a talented bartender named Ben Simpson at Motel Bar in Wellington, New Zealand. Simpson is the creator of Man O’War Gunpowder Rum, which is made of blended rums infused with black gunpowder and other ingredients. Simpson had also read about Blackbeard’s explosive concoction, which got him to thinking: sailors used to add all sorts of things to their rum to make it more palatable … charcoal was sometimes used in casks aboard ships to keep the contents tasting fresh … gunpowder contains a lot of charcoal … and, well, why not? “A lot of it is my own hypothesis,” Simpson admits. In addition to gunpowder, Man O’War is infused with tobacco and chili peppers. “Mostly I’m making assumptions about sailors and how they drank crazy things.”
Simpson is not yet selling his rum by the bottle—he serves it at his bar and trades it for other exotic liquors—but I had a chance to try it recently when a sample arrived in the mail. It came in Simpson’s standard packaging: a used whiskey bottle tightly wrapped in a brown paper bag, the cap sealed with duct tape. Man O’War smelled a bit like you’d imagine sailors’ quarters smelled 300 years ago—a little musty, a touch sulfurous. But the rum had an outsize taste that was beguiling and somehow antiquarian. A brief chocolaty sweetness was quickly offset by leathery notes, with a powdery dryness that seemed to trigger an implosion, rather than an explosion, in the mouth.
I theorized that it would do well in a rum Manhattan, and I made one with equal parts Demerara rum from Guyana and Man O’War. The drink was sublime. As I sipped, I looked over the bottle’s label and noted that it was “approx. 49 percent alcohol,” which seemed to invite further testing. I gathered up the rum, some gunpowder, and a box of matches, then headed out to the yard.
I mean, what could go wrong?