University of Virginia Historical Collections at the Claude Moore Health Sciences Library

American Medicine and Preparation for the Lewis and Clark Expedition

Thomas Jefferson and Medicine, Meriwether Lewis, Lucy Marks, Benjamin Rush, Medicine and Medical Equipment Taken by the Corps of Discovery

Thomas Jefferson believed that colonial medicine was based on theory, rather than hard science, and strongly disapproved of the medical profession’s overuse of purging, cathartics, and bloodletting therapies. Instead, Jefferson’s medical theory rested on preserving good health. He advocated eating little red meat but great quantities of vegetables, drinking only weak wines, abstaining from tobacco products, and engaging in daily exercise. To treat disease, Jefferson reasoned that the body could better restore itself if left alone. Jefferson was a great believer in natural remedies, and at Monticello he grew a variety of herbal plants to use as medicines. Jefferson believed herbs could be utilized to establish a natural balance of the body with its environment. Lavender, marjoram, sage, thyme, wormwood, rosemary, and chamomile are a few herbs Jefferson planted. While Jefferson generally distrusted physicians and the common medical practices of the day, he did rely on Dr. Robley Dunglison to treat his severe diarrhea, a reoccurring problem during the last quarter of his life. For Jefferson’s intestinal problem, Dunglison prescribed rhubarb, magnesia, and laudanum.

The Medical Training of Meriwether Lewis

The trek of the Lewis and Clark Expedition to the Pacific Ocean and back was an arduous 8,000 miles laden with unknown natural perils, potentially hostile natives, and unavoidable health problems. Surprisingly, the well-planned expedition did not include a trained doctor. Some scholars have called this omission a serious defect. However, Thomas Jefferson was not prone to oversight. Instead, Jefferson, who generally distrusted the medical community, relied on Meriwether Lewis to act as the primary physician. Lewis was well-suited for this role. He had acquired much herbal lore under the guidance of his mother, Lucy, a noted herbalist in the Charlottesville area. This knowledge stood Lewis in good stead for as an officer, Lewis’s duties also included caring for the health of his soldiers. Even with this medical background, Jefferson required that Lewis receive supplementary medical training from America’s premiere physician, Benjamin Rush. Under Rush’s tutelage, Lewis learned the typical medical theory and practice common of the day.

Lucy Meriwether Lewis Marks, Mother and Herb Doctor

Lucy Meriwether Marks

Lucy Meriwether Marks by John Toole. Anonymous Gift, 1947.2. University of Virginia Art Museum.

In 1769 William Lewis brought his new bride, Lucy Meriwether, to his family estate, Locust Hill, a plantation situated on Ivy Creek just west of Charlottesville. Their union produced three children—Jane, Meriwether, and Reuben. When the Revolutionary War broke out, William Lewis volunteered to serve without pay. While Lieutenant Lewis was off fighting the British, Lucy had her own close encounter with enemy soldiers at Locust Hill. On this occasion, drunken British soldiers (paroled prisoners from Burgoynes’ captured army) burst into the family home. Lucy grabbed a rifle off its pegs and drove them away. In 1779, while home on leave, Lieutenant Lewis nearly drowned attempting to cross a flooded Rivanna River. Pneumonia set in, and two days later he died. Typical for women in that day, Lucy remarried six months later to Captain John Marks. The family relocated with Marks to Georgia, where Lucy Marks gave birth to two more children. Upon her second husband’s death in 1791, Lucy Marks returned to Locust Hill where she lived until her death in 1827 at age eighty-five. Lucy Meriwether Lewis Marks distinguished herself as a noted local herb doctor. In the late eighteenth century, few career paths were available to women. Typically, a woman’s role was limited to household duties. Such duties involved tending to family health needs, including those of slave families. Lucy’s skills extended from dispensing medicine to her own children and slaves to her neighbors for miles around. Herbal medicine was popular in Colonial America. A distrust of regular physicians and their use of “heroic medicine,” as well as high fees, led people to consult with a physician in only the most urgent cases. Families tended to treat themselves first with medicinal herbs grown in their gardens, such as chamomile, lavender, sage, and thyme. Lucy grew a variety of medicinal plants that she used to produce concoctions, decoctions, poultices, and other medical compositions to treat the sick. Lucy Marks’s interest in health issues and care continued with her children. Meriwether Lewis’s full brother, Reuben, and half-brother, John, both became trained physicians. Meriwether Lewis also demonstrated aptitude in the field. In evaluating Lewis’s medical abilities, scholar J. Howard Beard states, “American medicine lost a great leader when Meriwether Lewis responded to the urge of adventure…His natural gifts, if trained would have undoubtedly qualified him as a most worthy successor to Benjamin Rush.”

Dr. Benjamin Rush, America’s Premiere Physician

“Capt. Lewis is brave, prudent, habituated to the woods, & familiar with Indian manners & character. He is not regularly educated, but he possesses a great mass of accurate observation on all the subjects of nature which present themselves here & will therefore readily select those only in his new route which shall be new.” —Thomas Jefferson to Benjamin Rush, February 8, 1803

Benjamin Rush

Benjamin Rush. From American Medical Biography by James Thacher (1828).

During Meriwether Lewis’s lifetime, Benjamin Rush was the premiere physician in America. At fifteen Rush graduated from college and for the next five years served as a medical apprentice to a leading Philadelphia physician. Wishing to further his medical education, Rush traveled to Edinburgh and studied under the renowned medical teacher, William Cullen. Completing his thesis on the digestion of food, Rush graduated at the age of twenty-two and returned in 1769 to Philadelphia, where he received a professorship of chemistry at the College of Philadelphia. Rush quickly became a prominent and leading citizen in America as he wrote and spoke on nearly every medical, social, or political matter. During his lifetime, Rush sought to improve the health care needs of the poor, studied the causation of yellow fever, and explored mental illness for which he is called the “Father of American psychiatry.” Socially he advocated the restriction of alcohol and tobacco, the abolition of slavery, and universal education. Politically he was active in the revolution against Great Britain. Rush aided Thomas Paine in the writing of Common Sense, and he was one of five physicians to sign the Declaration of Independence.

In his theory of bleeding …, I was ever opposed to my friend Rush, whom I greatly loved; but who had done much harm, in the sincerest persuasion that he was preserving life and happiness to all around him. —Thomas Jefferson, October 7, 1824

Although Rush could never completely convince Jefferson of the efficacy of physicians, Benjamin Rush and Thomas Jefferson were good friends. Therefore, it is not surprising that Jefferson sent Meriwether Lewis to Philadelphia in the spring of 1803 to solicit medical advice from Rush. Rush no doubt lectured Lewis on his theory that all disease was related to tension in the blood vessels. As a result, Rush’s prescribed therapy for all disease was bloodletting. Rush proposed that bleeding would help a slow or fast pulse, open or close the bowels, decrease fever as well as chilling, and relieve a coma but also induce sleep. Rush was never concerned about removing too much blood, in fact, he believed as much as four-fifths of the body’s blood could be removed. Rush was impressed with Lewis and wrote Jefferson, “His mission is truly interesting. I shall wait with great solicitude for its issue. Mr. Lewis appears admirably qualified for it. May its advantages prove no less honorable to your administration than to the interest of science.”

Benjamin Rush’s Pills

Fifty dozen “Rush’s pills” were included in the medical pharmacy taken on the expedition. “Rush’s pills,” otherwise known as “Thunderclappers,” combined calomel and jalap into an explosive cathartic. Calomel (six parts mercury to one part chlorine) was used as a purgative and jalap as a laxative. The depleting aspect of this medication was thought to rid the body of any “morbid” elements contained mainly in the blood. Lewis and William Clark used the pills to treat malaria, an accidental arsenic poisoning, pleurisy, and dysentery.

Benjamin Rush’s Rules for Healthy Living

Rush submitted to Lewis ten health commandments to subscribe to for the Corps of Discovery.

  1. Flannel worn next to the skin, especially in wet weather.
  2. Always to take a little raw spirits after being very wet or much fatigued; and as little as possible at any other time.
  3. When you feel the least indisposition, fasting and rest; and diluting drinks for a few hours, take a sweat, and if costive take a purge of two pills every four hours until they operate freely.
  4. Unusual costiveness is often the sign of an approaching disease. When you feel it, take one or two of the opening pills.
  5. Where salt cannot be had with your meat, steep it a day or two in common lye.
  6. In difficult and laborious enterprises or marches, eating sparingly will enable you to bear them with less fatigue and more safety to your health.
  7. Washing feet with spirit when chilled, and every morning with cold water.
  8. Molasses or sugar with water with vit. [victuals] and for drink with meals.
  9. Shoes without heels.
  10. Lying down when fatigued.

Medicines and Medical Equipment on the Lewis and Clark Expedition

Herbal Medicine: The Choke Cherry

Choke Cherry

Choke Cherry. Courtesy of Karen Pearson McKenzie.

Lewis’s knowledge about herbs proved helpful on the expedition. Having broken off from the main party to search for the Great Falls of the Missouri River, Lewis was without the Corps’ medical supplies. Weak with violent intestinal pain and a high fever, Lewis relied on herbal medicine. He ordered his men to gather twigs of the choke cherry, a shrub first discovered in Virginia. Lewis removed the poisonous leaves and cut the twigs into two inch pieces. Boiling the twigs produced “a strong black decoction of an astringent bitter tast[e].” Lewis drank two pints, one at sunset and one an hour later, and found that he was able to have “a comfortable and refreshing nights rest.” Rising early the next morning, Lewis downed another pint and, feeling revived, set out on a 27 mile hike.

Medical Equipment

Clyster c. 1825

Clyster c. 1825. Historical Collections & Services, CMHSL.

Medical equipment in the early 19th century was limited. Penis syringes and clysters were taken along in anticipation of treating venereal disease. Medicine, particularly mercury, was placed in the clyster and injected into the penis or anus for treatment. Ointments or salves were also used topically to treat the disease. Clysters could also be used for administering enemas.



Lancet, c. 1800s

Lancet, c. 1800s. Historical Collections & Services, CMHSL.

Lancets were used for blood-letting, a popular therapy in the nineteenth century and one enthusiastically espoused by Benjamin Rush. Lewis and Clark were equipped for the expedition with “six best lancets.” The lancet, a small sharp knife, was used to penetrate a vein without severing or nicking the pulsating artery beneath it. A strategically placed bowl collected the blood flowing from the incision.



Dental tooth key or extractor

Dental tooth key or extractor, circa 1800-1849. Historical Collections & Services, CMHSL.

There is no record of dental problems on the expedition except for a couple of toothaches. However, the lack of fresh fruit in the explorer’s diet might have caused scurvy which can affect the teeth. Additionally, the generous use of mercury in treating the abundance of venereal disease could have produced gingivitis and loose teeth. The medical equipment list also included a tourniquet which could have been used in the event of an amputation. Journal records do not indicate that the tourniquet was used on the expedition for any purpose.


Medical Supplies Taken

Typical nineteenth-century medical chest

Typical nineteenth-century medical chest. Historical Collections & Services, CMHSL.

The task of preparing for the expedition must have been mind-boggling. Meriwether Lewis had to anticipate everything from the essential, firearms, to the mundane, fishhooks. Countless supplies needed to be obtained — enough to last for an indefinite period of time and for an indeterminate number of men. Lewis spent much of the spring of 1803 in Philadelphia purchasing supplies such as scientific instruments, dry goods, camping gear, oiled linens, and presents to give to the Indians. One stop he made on May 26, 1803, was to a store owned by George Gillaspy and Joseph Strong. Here Lewis spent a grand total of $90.60 on medical supplies for the expedition. The lists of medicines and medical equipment procured accurately reflect the state of the medical profession in the early nineteenth century. One third of the total cost was spent on fifteen pounds of Cinchona bark, containing quinine, an effective treatment for malaria. Another effective drug purchased was laudanum, a tincture of opium, used as a pain killer and sleeping aid. The rest of the items acquired deal with purging through vomiting or enemas. Lewis took 600 of “Rush’s pills” on the expedition as a means to generate a powerful and explosive purgative. Clover, nutmeg, and cinnamon were also purchased to add to the medicine in an attempt to conceal its foul taste.

Medicines Purchased
Item Description Cost
15 lbs. pulverized Cort. Peru [Peruvian Bark or Cinchona] Quinine/fever reducer $30.00
1/2 lb. pulverized Jalap Laxative/purgative $ 0.67
1/2 lb. pulverized Rhubarb Laxative/purgative $ 1.00
4 oz. pulv. Ipecacuan Emetic/purgative $ 1.25
2 lb. pulv. Cream Tartar Purgative/diuretic $ 0.67
2 oz. Gum Camphor Stimulant/diaphoretic $ 0.40
1 lb. Gum Assafoetid[Assafoetic/Assafoedita] Purgative $ 1.00
1/2 lb. Gum Opii Turk. opt. Opium/pain killer $ 2.50
1/4 lb. Tragacanth Gum used to bind pills $ 0.37
6 lb. Sal Glauber Purgative $ 0.60
2 lb. Sal Nitri [saltpetre] Treatment for fevers/gonorrhea $ 0.67
2 lb. Copperas Metal used in making inks $ 0.10
6 oz. Sacchar. Saturn. opt.[Sugar of lead/lead acetate] Treatment for eye problems and gonorrhea $ 0.37
4 oz. Calomel [Mercurous chloride] Purgative/treatment for syphilis $ 0.75
1 oz. Tartar Emetic Emetic $ 0.10
4 oz. Vitriol Alb. [White Vitriol (Zinc Sulfate)] Treatment for eye problems $ 0.12
1/2 lb. Rad. Columbo [Root of columbo] Tonic for indigestion and diarrhea $ 1.00
1/4 lb Elix. Vitriol [Elixir of vitriol (ethylsulfuric acid)] Tonic for stomach problems $ 0.25
1/4 lb. Es. Menth. pip. [Essence of menthol or peppermint] Treatment for digestive problems $ 0.50
1/4 lb. Bals. Copaiboe [Balsam of Copaiba] Treatment for rheumatism and gonorrhea $ 0.37
1/4 lb. Bals Traumat [Compound tincture of Benzoin] Treatment for cuts and abrasions $ 0.50
2 oz. Magnesia Purgative $ 0.20
4 oz. Laudanum [Tincture of opium] Pain reliever $ 0.50
2 lb Ung. Basilic [Compound of pine resin, yellow wax, and lard] Ointment or salve $ 1.00
1 lb. Ung. Calimin Astringent $ 0.50
1 lb. Ung. Epispastric Blistering agent $ 1.00
1 lb. Ung. Mercuriale [Mercury]; diaphoretic Ointment or salve for treatment of syphilis and other venereal diseases $ 1.25
1 Emplast. Diach. S. [Diachylon simple] Plaster or salve made of the juices of several plants $ 0.50
50 doz. Bilious Pills to order of B. Rush [Combination of calomel (mercurous chloride) and jalap] Purgative/laxative $ 0.10 per dozen or $5 total
2 oz Nutmegs Flavoring for oral medicines $ 0.75
2 oz. Cloves Flavoring for oral medicines $ 0.31
4 oz. Cinnamon Flavoring for oral medicines $ 0.20


Medical Equipment
Item Description Cost
1 Set Pocket Insts. small $9.50
1 Set Teeth Insts. small $2.25
1 Clyster Syringe Used for administering enemas $2.75
4 Penis Syringes Used for treatment of gonorrhea $1.00
3 Best Lancets Used for bleeding or blood-letting $0.80 ea. or $2.40 total
1 Tourniquet For amputations $3.50
2 oz. Patent Lint Linen or fleece-like material for poultices and dressing wounds $0.25
6 Tin Canisters $0.25 each or $1.50 total
3 8 oz. Gd. Stopd. bottles $0.40 each or $1.20 total
5 4 oz. Tinctures bottles $1.85
6 4 oz. Salt Mo. $2.22
1 Walnut Chest $4.50
1 Pine Chest $1.20
1/4 lb. Indian Ink Black pigment in the form of sticks used for writing $1.50
2 oz. Gum Elastic Rubber from the buckhorn plant; bark has some medicinal qualities, however; not soluble in water, and may have been used to seal containers $0.37