Mercury Laxatives: Lewis And Clark's Evidence

The Lewis and Clark Expedition, which ran from May 1804 to September 1806, is one of the most famous and historic American expeditions of all time. The group, led by Captain Meriwether Lewis and Second Lieutenant William Clark, stopped at over 600 sites during their 28-month journey. To combat frequent constipation, Lewis and Clark ingested mercury-laced laxatives, which were common at the time. Archaeologists have been able to identify one of the group's campsites by testing old latrine areas for mercury. This technique has helped to plot out certain points along the route of the expedition, including Travelers' Rest in Montana.

Lewis and Clark's laxatives were called thunderclappers or thunderbolts

Lewis and Clark's laxatives were called "thunderclappers" or "thunderbolts". The laxatives were also referred to as "Dr. Rush's Bilious Pills", named after the physician who prescribed them, Dr. Benjamin Rush.

The pills were a combination of mercury and mercury chloride (calomel). They were intended to be a cure-all and were believed to empty excessive bile, which was thought to cause a variety of ailments.

The laxatives were aptly named, as they caused profound diarrhoea and violent purging. Clark described the desired effect in his journal: "things were coming out of all parts of your body".

The mercury in the pills left a unique signature in the soil, which archaeologists have used to identify the location of latrines and, subsequently, campsites along the Lewis and Clark trail.

The laxatives were obtained from Benjamin Rush, a friend of Thomas Jefferson

The Lewis and Clark Expedition, which took place from May 1804 through September 1806, is one of the most famous and historic American expeditions of all time. Meriwether Lewis and William Clark were commissioned by President Thomas Jefferson to establish a clear and defined route of trade and travel across the new western territories. The expedition was a gruelling one, with the explorers suffering from gastrointestinal issues due to their diet of dried meat and game meat washed down with river water.

To combat these issues, Lewis and Clark turned to a supply of 1,300 pills known as "Dr. Rush's Bilious Pills" or "thunderclappers". These pills were obtained from Benjamin Rush, a friend of Thomas Jefferson and a preeminent physician at the time. Rush was a proponent of "heroic medicine", which involved extreme purging of the body to flush out illnesses. His pills contained a high dose of mercury chloride, also known as calomel, which acted as a powerful laxative.

The use of these mercury-laden laxatives has had an unexpected benefit for present-day archaeologists. Because mercury does not decompose, it has been possible to identify the presence of these pills in the latrines used by Lewis and Clark. By testing soil samples for elevated levels of mercury, archaeologists have been able to identify specific campsites used by the expedition, including Travelers' Rest in Montana.

While the use of mercury as a purgative was a common practice at the time, it is important to note that it was a dangerous treatment. The men of the expedition were essentially ingesting mercury poisoning, and it is remarkable that they survived the experience.

The pills contained mercury chloride, also known as calomel

The pills that Lewis and Clark took for constipation and syphilis contained mercury chloride, also known as calomel. The pills were called "Dr. Rush's Bilious Pills", named after Benjamin Rush, a Philadelphia-based physician and friend of Thomas Jefferson. Rush was an advocate of "heroic medicine", which involved extreme purging of blood, bile, and other bodily substances. He believed that gastrointestinal problems, especially constipation, caused various diseases, and that purging the GI tract would treat these diseases.

The pills contained a large amount of mercury chloride, also known as calomel, a powerful laxative. In fact, the pills were so potent that they were nicknamed "thunderclappers" or "thunderbolts". The mercury in the pills would have killed bacteria, including the bacterium that causes syphilis, but it was also toxic to the human body. Luckily for Lewis and Clark, the mercury in the pills was insoluble, so it passed through their bodies without being absorbed. However, it still caused hours of diarrhoea and slowly poisoned them over time.

The high mercury content of the pills has had an unexpected benefit for archaeologists and historians. Because mercury does not decompose, it has been possible to identify campsites along the Lewis and Clark trail by testing old latrine contents for mercury. This technique has helped to identify several sites, including Pompeys Pillar on the Yellowstone River and Travelers' Rest in Montana.

The pills were used to treat constipation and syphilis

The Lewis and Clark expedition, which ran from May 1804 to September 1806, is one of the most famous and historic American expeditions of all time. Meriwether Lewis and William Clark, along with the rest of their 33-member Corps of Discovery, embarked on a long trek from St. Louis to the Pacific Ocean to explore unknown territory and establish trade with the Native Americans.

The group's diet consisted of nine pounds of dried meat, including beaver tail, buffalo, and elk, as well as whiskey. As a result, they experienced frequent gastrointestinal issues, including constipation. To treat these issues, the group relied on mercury-laced pills, known as "Dr. Rush's Bilious Pills" or "thunderclappers". These pills were created by Benjamin Rush, a Philadelphia-based physician and friend of Thomas Jefferson, who believed in the concept of heroic medicine, which involved extreme purging of the body.

While the pills were effective laxatives, they were also very harmful, essentially causing mercury poisoning in those who ingested them. The high mercury content in the pills was effective in treating constipation and also killing the bacteria that caused syphilis. The men experienced symptoms of mercury poisoning, including drooling and salivation, though they did not understand the cause of these symptoms at the time.

The use of these mercury-laced laxatives has provided a unique signature that has helped archaeologists and historians identify the locations of the group's campsites. By testing old latrine contents for mercury, researchers have been able to pinpoint specific sites along the expedition's route, including Travelers' Rest in Montana, which has been designated as a state park.

Archaeologists have used the mercury in old latrines to identify Lewis and Clark campsites

The Lewis and Clark Expedition, which ran from May 1804 to September 1806, is one of the most famous and historic American expeditions of all time. Led by Captain Meriwether Lewis and Second Lieutenant William Clark, the Corps of Discovery set out from Camp Dubois in Illinois and travelled west to the Pacific Coast, following the course of the Missouri River.

The group stopped at over 600 locations during their 28-month journey, and while they only spent a day at most of these sites, they still needed to eat, sleep, and dig latrines for their waste. Lewis and Clark's diet consisted of nine pounds of dried meat per day, including beaver tail, buffalo, and elk, as well as a considerable amount of whiskey. As a result, the men suffered from frequent constipation and turned to laxatives for relief.

One such laxative was "Dr. Rush's Bilious Pill," which contained a large amount of calomel, or mercury chloride. This remedy was commonly prescribed at the time to treat constipation, but it was actually a form of mercury poisoning. The mercury in these pills did not decompose and remained in the latrine pits for centuries.

Archaeologists have taken advantage of this fact to identify Lewis and Clark campsites by testing old latrine areas for the presence of mercury. This technique has successfully identified the campsite at Travelers' Rest in Montana, located on the banks of Lolo Creek south of Missoula. By combining evidence from soil samples, journal entries, maps, and a military guidebook, researchers were able to confirm that this was indeed a campsite used by the Corps of Discovery during their historic journey.

While the use of mercury-laced laxatives may seem unusual today, it provides a unique signature that has proven invaluable in retracing the steps of Lewis and Clark and filling in gaps in our understanding of their expedition.

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