Gulp: Adventures on the Alimentary Canal (17 page)

What about a scuba diver in a wetsuit with a tank of oxygen? How long could he survive in a tiger shark? Christiananswers.net puts forth an intriguing digestive loophole that, were it true, would have worked in his—or for that matter, Jonah’s—favor: “As long as the animal . . . swallowed is still alive, digestive activity will not begin.”

T
HIS PERSISTENT BIT
of digestive bunk can be traced to eighteenth-century Scottish anatomist John Hunter, an otherwise estimable scientist who more or less invented modern surgery. In the course of hundreds of dissections, Hunter would come across cadavers with mysterious lesions in the stomach wall. He first assumed, reasonably enough, that the lesions had been the cause of death. But the condition was turning up even in vigorous young men killed in brawls, including one man done in by a blow to the head with an iron poker. In this case, too, the man’s stomach was dissolved clear through, Hunter noting that the contents of his supper—cheese, bread, cold meat, and ale—had spilled into the body cavity. There are several things one might take away from this case: that pub fare has changed little in two hundred years; that the owners of drinking establishments would do well to keep the fireplace tools behind the bar. Hunter came away with the realization that the inexplicable lesions he’d been seeing were not disease but auto-digestion. The stomach tissue, he noted, was damaged in the same way the digested cold cuts were. In other words, the stomach, at death, begins to digest itself.

This raised the question, What keeps it from doing so while the person is alive? Hunter’s explanation—and the source of the Christiananswers.net piffle—was that living tissue exudes some sort of vital force field that protects it. “Animals . . . possessed of the living principle, when taken into the stomach, are not the least affected by the powers of that viscus . . . ,” stated Hunter in a 1772 text. Ditto humans taken in: “If one conceive a man to put his hand into the stomach of a lion, and hold it there,” wrote Hunter in a separate text, “. . . the hand would not in the least be digested.” A small and temporary consolation, it must be said.

French physiologist Claude Bernard didn’t buy it. Bernard took some animals into the stomach. The year was 1855. The stomach belonged to a live dog and had been given a fistulous opening similar to the one that had enabled William Beaumont to spy on the digestive activities of Alexis St. Martin a few decades (and chapters) earlier. Bernard restrained the dog and then “introduced,” through the fistula, the hindquarters of a frog. After forty-five minutes, the frog’s legs were “largely digested”—nothing new to a Frenchman, except that here the frog was still alive. The experiment, concluded Bernard, “shows that life is not an obstacle to the actions of gastric juices.” And that cruelty was not an obstacle to the actions of Claude Bernard.
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In 1863, English physiologist Frederick W. Pavy extended Bernard’s findings to mammals. In keeping with the French market-day theme, Pavy selected a rabbit. He inserted one of its ears into the stomach of yet another fistulated dog while it was digesting a meal. Four hours later, a half inch of the tip was “almost completely removed, the small fragment only being left attached by a narrow shred to the remainder of the ear.” Again, digestion had proceeded unthwarted by the “living principle” or any sense of decency.

So Hunter was wrong. No vital force exists to protect a living being from the effects of the gastric secretions. Why is it, then, that stomachs don’t digest themselves? Why do one’s stomach juices handily digest haggis or tripe but not the very stomach that secretes them?

It’s something of a trick answer. In fact, stomachs can digest themselves. Gastric acid and pepsin digest the cells of the stomach’s protective layer, or mucosa, quite effectively. What no one in Hunter’s day realized is that the organ swiftly rebuilds what it breaks down. A healthy adult has a new stomach lining every three days. (More clever stomach tricks: key components of gastric acid are secreted separately, lest they ravage the cells that manufacture them.) The stomachs of John Hunter’s cadavers managed to burn holes in themselves because the mucosa-producing machinery shuts down at death. If someone dies in the midst of a meal—particularly in a warm clime, where weather stands in for body heat—the digestive juices continue to act though the restoration work has stopped.

If you must spend time in a digestive organ, I recommend the penguin stomach. Penguins can shut down digestion by lowering the temperature inside their stomach to the point where the gastric juices are no longer active. The stomach becomes a kind of cooler to carry home the fish they’ve caught for their young. Penguins’ hunting grounds may be several days’ journey from the nest. Without this handy refrigerated mode, the swallowed fish would be completely digested by the time the adults get back—“like going shopping and eating everything you bought on the way home,” as marine biologist Terrie Williams put it.

O
NE REASON THE
notion of living principle gained traction in John Hunter’s mind was that it offered a medical explanation for stomach snakes. As far back as Babylon and ancient Egypt, people had been coming to doctors with complaints of reptiles or amphibians living inside them. The malady hit an especially brisk stride in the late eighteenth century. “Thence it is,” wrote Hunter in his 1772 paper on the living principle, “that we find animals of various kinds living in the stomach, or even hatched and bred there.” Through the end of the century and likely beyond, biologists of imposing stature—not just Hunter, but also Carl Linnaeus—believed that frogs and snakes could live in humans as parasites, nourished by daily deliveries of swallowed food. Medical historian and author Jan Bondeson tracked down some five dozen case reports in medical journals from the seventeenth, eighteenth, and nineteenth centuries. Eighteen involved lizards or salamanders; seventeen posited snakes; fifteen claimed frogs; and twelve toads.

Despite the varied taxonomy and geography represented by these cases, the basic premise is more or less the same. The patient, vexed by odd sensations or pains in the abdomen, suddenly remembers a visit to the country. While walking home at night, the tale typically goes, he stops to drink from a pond—or marsh or rivulet or spring. It’s nighttime, and he cannot see what he is swallowing. Or he is drunk and does not notice. Sometimes he believes he swallowed eggs, other times the actual animal. In a few instances, the person lies down to sleep or passes out, whereupon some elongate, cold-blooded creature slithers down his esophagus and into his gut.

What cements the delusion, in the patient’s mind, is the timely sighting of an animal in the chamber pot. “When at stool, she had unusual pain in the rectum, and afterwards she thought she perceived something moving in the pot,” reads a typical case report, from 1813. Often the patient has been given a cathartic to relieve his symptoms. As here, in the 1865 case report of a stomach slug: “The patient had taken an injection per anum
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. . . and immediately afterward something attracted his attention by moving about under his clothes.”

The likelier chain of events, of course, is that the creature had been in the pot or the bed, unnoticed, all along. And that the authors who wrote these papers were either lazy thinkers or, equally possible, crafty career opportunists. Cases like these, taken at face value, were irresistible medical curiosities; reports of them were sure to be published in medical journals and newspapers of the day, spreading the physicians’ names and boosting their status.

Then again, to be fair, some of the details conspired to lend credence to the claims. Like the contemporary urban myth, tales of stomach frogs and “bosom serpents” persisted because they have truthiness. Few would believe a story about a man with a mammal alive in his digestive tract—though Bondeson tracked down one instance of a stomach mouse—but an indwelling frog has biological plausibility. Sideshow regurgitators used frogs because they can absorb oxygen from water through their skin. Swallow a frog in a large glass of water, and it will survive—at least through the end of the act.

Cold-blooded animals in general have lower metabolic needs. Because they’re not using food energy to heat themselves, they manage with less. Some frogs all but shut down in winter. “I wouldn’t be surprised if live frogs were gutted out of bass in winter, by fisherman,” wildlife biologist Tom Pitchford told me. But a human belly isn’t cold. It’s tropical. Around 1850, in Germany, physiologist-zoologist Arnold Adolph Berthold, seeking to put an end to stomach-frog folly, put some northern European species of frogs and lizards in body-temperature water. The adults died, and the spawn putrefied.

That snakes top the list is not surprising. On top of their overall cold-blooded hardiness, they seem to have a special knack for enduring gastrointestinal confinement. Phillip Clapham, the whale biologist I pestered at the start of this chapter, related the story of Gracie, a Doberman mix who once vomited a two-foot garter snake onto Clapham’s dining room floor during a dinner party. As he tells it, his wife at the time, assuming the snake was dead, picked it up in a wad of paper towels and then “nearly dropped it when its little forked tongue came out.” Clapham insists Gracie hadn’t been outside for at least two hours. “It had been in there quite a while.”

University of Alabama snake digestion researcher Stephen Secor once watched a king snake regain consciousness after somewhere between ten and twenty-five minutes inside another king snake. He had put the two in the same tank, not realizing one species considered the other dinner. Secor left the room, and when he returned, dinner was “down in.” He pulled them apart, and was relieved and surprised to note that dinner still had a heartbeat.

Nonetheless, a brief sojourn is different from permanent immigration. More reputable doctors of yore recognized stomach snakes for what they were: delusions inspired by gastric symptoms. The underlying condition was typically mundane: ulcer, lactose intolerance, intemperance, gas. You could often tell what was going on from the patients’ descriptions of their tenant’s habits. Andrew S.’s snake acted up whenever he drank alcohol or milk. “He will never allow me to drink whiskey,” S.’s physician Alfred Stengel quotes him as saying in the 1903 paper “Sensations Interpreted as Live Animals in the Stomach.” “He hates that worse than anything else.” The stomach snake of a woman in Castleton, Vermont, circa 1843, was most active after “any considerable indulgence in gross food.”

Occasionally there was nothing wrong at all, just the ordinary grumbling and gurgling—the borborygmi—of the gut. The surgeon Frederick Treves, writing in the late 1800s, described five cases of patients complaining of wriggling movements or of live snakes inside them. Upon operating and finding nothing beyond the normal motions of a healthy digestive tract, he coined a term: “intestinal neurosis.” It exists today, minus the snakes. One gastroenterologist told me about a sad soul who wandered the motility clinics of North America with a video of himself in his underwear, pennies stacked on his abdomen to show the alarming motions of his (perfectly normal) intestines.

Sometimes a patient would manage to capture the alleged tormentor and bring it in to show the doctor. While some physicians kept the animals for display in cabinets of curiosity—or, on occasion, as pets—those of a more scientific bent recognized an opportunity for forensic fact-checking. Jan Bondeson relates a famous case from the seventeenth century of a twelve-year-old who complained of abdominal cramping and, over an unspecified span of time, allegedly vomited twenty-one newts, four frogs, and “some toads.” One of the youth’s physicians had the bright idea of dissecting the amphibians’ stomachs. If the story were true, the food inside the little stomachs should reflect the creatures’ gastrointestinal habitat. Instead the stomachs contained half-digested insects. In 1850, Arnold Adolph Berthold, our man of the putrefied frog spawn, approached curators at German medical museums whose collections included reptiles and amphibians allegedly vomited or excreted after years of residence in a human digestive tract. Here again, when specimens’ stomachs were opened, many were found to hold insects in various stages of dissolution.

The most directed experimental debunking was carried out by J. C. Dalton, a physiology professor at the College of Physicians and Surgeons of New York. Over a span of several months in 1865, Dalton had twice been visited by flummoxed colleagues bearing “discharged” slugs in jars of alcohol. One was said to have come from a boy who had been suffering three weeks from diarrhea. The usual narrative ensued: “It was during this diarrhea that the slugs were passed. On that day, the mother, on removing the clothes from the child after a fecal evacuation, found among them one of the animals, alive and moving.” She assumed he’d inadvertently consumed slug eggs while eating garden greens on a family visit in the countryside, where the boy had “passed a part of the summer”—an alarming verb choice under the circumstances.

Dalton was dubious. “I accordingly thought it worthwhile to institute some experiments, with a view of ascertaining how far such a thing might be possible.” Garden slugs were procured from a neighborhood lettuce bed. An assistant held a dog’s mouth open while Dalton placed four slugs, one at a time, at the far back of its mouth to get it to swallow without chewing. An hour later, Dalton took out his scalpel. He found “no recognizable traces of slug” anywhere along the dog’s alimentary canal. In subsequent experiments, just fifteen minutes rendered a slug “somewhat softened” and a salamander “exceedingly soft and flaccid,” and both dead.

“It is a curious psychological phenomenon,” wrote Dalton, “to witness the thorough confidence . . . and the fullness of detail with which intelligent persons will sometimes relate these stories. . . . When the accounts come to us second hand, we can always make abundant allowance for the natural growth of wonders, in passing from mouth to mouth. But even when the facts stated are those which came under the relator’s own observation, the discrepancy between his convictions and the truth may sometimes be equally remarkable.”