On Mackinac Island, old-fashioned fudge shops abound and visitors ride around its rocky shoreline in buggies or on bikes — motor vehicles are mostly prohibited to maintain its quaint charm. This popular Michigan vacation spot is deeply rooted in a history as a fur-trading outpost in the early 19th century. One building, though, was the unlikely spot of a important, and unsettling, ongoing science experiment.

The old general store on Mackinac Island, just off of the tip of Michigan’s Lower Penninsula, is lined with dark, lacquered shelves. Dried herbs and meat hang from the walls and large glass jars sit atop the front counter. It’s here where the accident occurred.



A period re-enactor stands before the general store display which has been recreated to look as it did in the early 1800s. (courtesy Mackinac State Historic Parks)

In the summer of 1822, a customer at the store accidentally fired a carelessly loaded shotgun. The bullet sank deep into the abdomen of Alexis St. Martin, a 19-year-old trapper who worked for the American Fur Company. Dr. William Beaumont, posted to the fort which still looms just above the store, hurried to St. Martin’s side, but feared the worst. The man’s left lung was singed and exposed, several ribs were broken, and bits of muscle were blown off.

In a few weeks, however, the wound began to heal and a year later, St. Martin was in good health — with one notable peculiarity. His skin had fused to the gunshot wound through the wall of his stomach, leaving an opening into his body. At first, the fistula was source of awe to Beaumont who could peer through it to the inner workings of a living man. Over the better part of the next decade, the doctor made this medical oddity the source of 238 experiments, which contributed previously unknown insights into the process of digestion.



Alexis St. Martin



Beaumont, an army doctor with only a few years of medical training as an apprentice, was an eager student of physiology. He began his experiments by pushing bits of food into St. Martin’s fistula on a spoon and monitoring the various lengths of time it took to break them down. Then he tried tying these morsels to string and withdrawing them at various intervals to monitor their decomposition within the gut. It was in this way that he discovered that the stomach uses hydrochloric acid to break down food.

He also collected samples of digestive “juice” from inside of St. Martin to mimic digestion in a cup. This showed him that digestion is mainly a chemical process, and not reliant on stomach muscles. His research also forged the basis for dietetics because of his study of the digestibility of different foods and the impact of stimulants like coffee or alcohol, as well as the impact of mood, temperature, and physical activity on digestion.



Engraving from Dr. William Beaumont’s book based on his experiments on Alexis St. Martin. (via connectictuhistory.org)

These experiments would often leave St. Martin feeling ill — nauseous or constipated — but it seems Beaumont had little regard for his patient as anything other than a test subject. Beaumont even called St. Martin a “villian” and “ungrateful” in his correspondence. The doctor took great strides to keep his human lab on hand, and hired him to help around his house for a time, and later got him a post in the U.S. Army so he could move along with Beaumont as he was posted to different military outposts across the country. This allowed the doctor to keep peering into St. Martin’s belly.

A French Canadian, St. Martin longed to stay in Quebec with his family, especially after he lost two children to sickness, but he may have felt he owed the doctor for saving his life. So he allowed the experiments to continue for eight years, refusing to do so only after the doctor published his book, Experiments and Observations on the Gastric Juice and the Physiology of Digestion in 1833.



A portrait of Dr. William Beaumont (via Wikimedia)

In 1833, the two parted ways for good. It is Mackinac Island on Lake Michigan — the site of the gunshot wound and Beaumont’s first experiments — where much of this unusual experiment’s history is preserved and even honored.

The general store where St. Martin was shot looks almost as it did on that June day in 1822, with its shelves stocked with items that would have been for sale at the time. The building was refurbished and made open to visitors to the island in 2000.

The retail store where Alexis St. Martin was shot (via Wikimedia)



A child plays with the interactive display about Dr. Beaumont’s experiment on St. Martin (courtesy Mackinac State Historic Parks)

Inside the old American Fur Company Store, an interactive display and informational panels outline the doctor’s experiments. A mannequin of St. Martin, with a macabre hole in its side, invites visitors to get a sense of his influential wound.

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