February 16-22, 1803

The second scientist consulted by Jefferson to help in the training of Meriwether Lewis was Benjamin Rush (1746-1813), perhaps the most respected physician in America. Rush had been a signatory of the Declaration of Independence, and was vice-president of the American Philosophical Society and professor of chemistry and medicine at the University of Pennsylvania. At the same time he was a surgeon at the Pennsylvania Hospital, and later took responsibility there for the mentally ill patients. His 1812 study, Medical Inquiries and Observations upon the Diseases of the Mind, is the first major American work on psychiatry. Rush was also one of the earliest proponents of veterinary medicine.

Benjamin Rush from Revolutionary Doctor by Carl Binger.

Caspar Wistar by Waugh, after Bass Otis from
We Proceeded On, 26:1. Original artwork at Mütter Museum, College of Physicians of Philadelphia.

During the 1793 yellow fever epidemic in Philadelphia, when a tenth of the population is estimated to have died, Rush was much admired for his courage in caring for his patients, many other physicians having fled the city. His belief in heavy bloodletting and purges, formed during his experiences in the earlier epidemic of 1762, was known as “heroic therapy,” and did not meet the approval of all of Rush’s colleagues, but he was consistent enough to apply that treatment (successfully) to himself when he came down with the fever.

Rush was also the President of the Pennsylvania Society for the Abolition of Slavery, and was followed in that post in 1813 by fellow physician Caspar Wistar.

Washington Feb, 28. 1803

Dear Sir

I wish to mention to you in confidence that I have obtained authority from Congress to undertake the long desired object of exploring the Missouri & whatever river, heading with that, leads into the Western ocean. About 10. chosen woodsmen headed by Capt. Lewis my secretary, will set out on it immediately & probably accomplish it in two seasons. 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. He has qualified himself for those observations of longitude and latitude necessary to fix the points of the line he will go over. It would be very useful to state for him those objects on which it is most desirable he should bring us information. For this purpose I ask the favor of you to prepare some notes of such particulars as may occur in his journey & which you think should draw his attention and enquiry. He will be in Philadelphia about 2. or 3. weeks hence & will wait on you.

. . . I pray you to accept assurances of my affectionate friendship & sincere respect.

TH: JEFFERSON

On the same day, Jefferson wrote a letter in similar language to Caspar Wistar (1761-1818), Rush’s colleague at the University of Pennsylvania, as professor of anatomy. Like Barton and Rush, he began his medical studies in the United States, and completed them at the University of Edinburgh in Scotland. Wistar was Rush’s assistant during the 1791 yellow fever epidemic, but disagreed with him on the regimen of “heroic therapy.” His anatomy classes at the university were so popular that they had to be subdivided. His two-volume System of Anatomy for the Use of Students of Medicine (1811 and 1814) was the first anatomy textbook in America. Wistar was also an early advocate for vaccination. His and Jefferson's joint paper on the Megalonyx or Giant Sloth that Jefferson had placed at the American Philosophical Society in 1799 was the first published study of vertebrate paleontology in the United States. Wistar followed Rush as president of the Abolition Society, and he was also an advocate for prison reform. Like Barton, Gallatin, and of course Jefferson, he had a deep interest in native American cultures.

The letter to Wistar is not reproduced here, as it is very close in contents and tone to the letter to Rush transcribed above.

Source: Jackson, Letters, items 11 and 12.

Further Reading: Binger, Carl. Revolutionary Doctor: Benjamin Rush (1746-1813). New York: W. W. Norton & Company, 1966.
Corner, George W., The Autobiography of Benjamin Rush. Princeton: Princeton University Press, 1948.
Goodman, Nathan G. Benjamin Rush, Physician and Citizen. Philadelphia: University of Pennsylvania Press, 1934.
Hawke, David Freeman. Benjamin Rush, Revolutionary Gadfly. Indianapolis & New York: The Bobbs-Merrill Company, Inc, 1971.
Neilson, Winthrop and Frances. Verdict for the Doctor: The Case of Benjamin Rush. New York: Hastings House, 1958.