The first document in the file was dated August 4, 1943, and addressed to Stanley Lovell at OSS—America’s espionage agency during World War II. It was from one of his British liaisons, and it referenced a memo from a gadget man in the British intelligence agency SOE (Special Operations, Executive). “Replying to your letter of the 6th July,” the memo began, as though we were headed for some dusty government protocol. And then veered abruptly off the tracks.
“Up to the present our employment of evil-smelling substances has been mainly for the purpose of contaminating individuals’ clothing.” The memo contained the secret formula for “S liquid” (S for stench), an oily mixture with a “highly persistent smell suggestive of personal uncleanliness.” Included as well were plans for two delivery systems: a gelatin capsule to be pierced with a pin, squirted, and “dropped immediately once the operation is completed,” and a small brass spritzing device midway between a perfume atomizer and a pesticide sprayer, the latter to be “carried about secreted in the hand or pocket.” I pictured a British operative’s wife stumbling upon one in the pocket of her husband’s blazer, lifting it in front of her face and squeezing the bulb, expecting cologne and receiving instead another disquieting hint that her spouse was not wholly forthcoming about the particulars of his career.
The goal: “derision or contempt.” The demoralization and alienation of German and Japanese officers in occupied countries. Allied espionage agencies were keen to find cheap, low-profile devices to put into the hands of saboteurs and resistance groups, motivated civilians eager to help the cause.
The OSS, with help from weapons developers at the National Defense Research Committee (NDRC), got to work on a stench of their own devising. In his memoir, which was published twenty years after the war, Lovell downplayed SAC-23—“Contaminator, Stench”—as “comic relief,” an antidote to the “grim, bloody and sordid” job of creating “new and special weapons to kill people.” But the thickness of the files and the detailed, deadpan formality of their contents indicate otherwise. The SAC-23 project dragged on for two full years, sapping the patience and clogging the in-boxes of seven majors,* eight lieutenants, four captains, and a wing commander.
Lovell’s original directive, as stated in his memoir, was for a substance with the “revolting odor of a very loose bowel movement.” (“Who, Me?” was Lovell’s cover name for SAC-23.) He wanted something to distribute among Chinese resistance elements for the purpose of humiliating Japanese officers. For some reason, Lovell believed the Japanese to be uniquely vulnerable to harassment of this nature: “A Japanese thought nothing of urinating in public, but he held defecation to be a very secret, shameful thing.” (Like racism.) The NDRC set forth additional requirements. It should have a “range” of at least ten feet “without backfire.” “It should be silent in operation.” Inconspicuous. Impervious to rain, soap, solvents. Conferring shame for a minimum of several hours.
A chemical engineering firm out of Cambridge, Massachusetts, was brought on board to develop the formula. The Arthur D. Little Company put their top odor and flavor man—their “Million Dollar Nose”—on the job. Ernest Crocker rose to the challenge like the reek off a landfill on a summer’s noon. “A stink among odors may be compared to a weed among plants, . . . a plant out of place, such as a potato in a flower garden,” he wrote in a background memorandum. In other words, context is key.? At an Italian deli counter, a whiff of butyric acid reads as parmesan cheese; elsewhere, vomit. Likewise, the odor of trimethylamine can be described as fishy or vaginal—as Crocker coyly put it, “pleasant or unpleasant according to circumstances.” Very few smells can be classed by their very nature, regardless of context, as repulsive. These were the ones the OSS needed: the “stink-makers.”
The main active ingredient of the Brits’ “S liquid” was skatole, an intensely fecal-smelling? compound produced by gut bacteria as they break down meat. Thus wrote Crocker in a second memo, breezily entitled “Facts about Feces.” Acids from digested carbohydrates, he went on, yield the sour notes of flatus. Trace amounts of hydrogen sulfide provide the telltale rotten egg stench. And so on. The takeaway being that it’s no simple task to make a man smell like shit. The smell of human feces is, like any in nature, staggeringly complex, comprising dozens if not hundreds of chemical compounds. (This is why novelty “fart sprays” smell abominable but not especially like farts.) A high-fidelity simulant would be a daunting and costly prospect.
And, Crocker felt, not optimally effective. “In general,” he wrote, “a mixture is best for it bewilders.” Olfaction, like taste, is a sensory security guard, an early detection system for chemicals that might be harmful. If you don’t recognize the smell, you can’t know that it’s safe. Over the millennia, humans who played it safe and backed away from strange smells were more likely to survive to pass on their genes. Thus an unidentifiable foul smell is a more potent weapon than one that is merely foul.
The more typical military application for “malodorants”—as modern olfactory nonlethal weapons are known—has been “terrain denial”: keeping (or getting) people out of a targeted piece of real estate: a Viet Cong tunnel, a terrorist hide, a weapons cache. Almost always, these have been cocktails of odors. In its “evil-smelling substances” memo, the SOE described tiny glass stench ampules distributed to resistance groups to be dropped on the carpet in known Nazi meeting places. The officers would unknowingly crush them with their showy black lion-tamer boots, and an unplaceable, rank sulfur-plus-ammonia stench would fill—and then empty—the room.
Our man Crocker got to work. He set up in-house “organoleptic testing” sessions to gauge the effectiveness of dozens of heinous blends. Organoleptic means “involving the sense organs.” It means you didn’t want to be employed at Arthur D. Little in the later months of 1943. Crocker eventually settled on a blend of skatole; butyric, valeric, and caproic acids; and a mercaptan: shit, vomit, smelly feet, goat, and rotten egg. Samples were prepared and delivered to the NDRC in two formats: a more intense “paste-form stink,” for smearing, and a liquid stink in a squirtable two-ounce lead tube. Crocker assured his clients that the latter would render a target “highly objectionable for not less than two hours at 70 F.” He promised nothing short of “complete ostracism,” concluding his report with a tagline surely unique in the annals of marketing: “as lastingly disagreeable as a product of this kind can be.”