Source 4: Reading -- The Philadelphia Experts

Andrew Ellicott Lancaster, Pennsylvania was Lewis’ first stop in the Philadelphia area. It was in Lancaster that the nation’s leading astronomer and mathematician lived. Ellicott was also an accomplished surveyor. President Jefferson had previously written Ellicott and requested that he tutor Lewis. Lewis spent three weeks working with Ellicott – longer than he anticipated. Lewis had much to learn about how to make celestial observations using scientific instruments such as a sextant and chronometer. In order to survey land, an understanding of latitude and longitude was needed. The position of heavenly bodies in the sky determined latitude and longitude. Lewis needed this knowledge in order to map the new territory. It was from his sessions with Ellicott that Lewis learned surveying and navigation skills.

Ellicott House

Dr. Benjamin Rush “Bring your party back safe.”

-President Jefferson’s instructions to Meriwether Lewis

In order for the mission to be successful, the men in the expedition needed to be healthy. Lewis needed expert medical advice on how to treat illnesses and give emergency medical treatment. Jefferson wrote to Dr. Rush in February of 1803 and requested that Rush mentor Captain Meriwether Lewis on the modern medicine of the day. Jefferson personally knew Rush and held him in high esteem. Dr. Rush was the most well-known physician in the nation during the late 1700s and early 1800s. He was the foremost authority on medical treatments. While people living today would either shudder in horror or laugh at his medical philosophy, it was the accepted treatment of the day. No clinical thermometers or stethoscopes were yet used. A very careful physical observation of the patient was necessary for treatment. The popular belief of the time was that all illnesses had to do with the blood. Dr. Rush was best known for promoting bloodletting and purging. Bloodletting was known as “bleeding” the patient – cutting the problem area open and draining the bad blood! Purging was accomplished with various types of medications that would expel fluids/solids from the body. Sweating was another treatment used. “Dr. Rush’s Bilious Pills” were popular purging pills. The pills were a mercury compound mixed with a laxative. Rush advised Lewis on other medicines such as diuretics and emetics to produce vomiting. Rush also advised Lewis on how to use lancets for bleeding and cleavers for amputations. A complete list of medical supplies and medicines to purchase was compiled for Lewis. Rush did, however, want something in return for his advice. He requested that Lewis complete a survey of the various Native American populations the Corps would encounter. Rush wanted information on their health, diseases, cleanliness, ceremonies, and medical treatments among other things. Dr. Benjamin Smith Barton Jefferson wanted to know all about the plants and animals in the unknown territory. He wanted records accurately describing their location and physical descriptions. He even wanted specimens (sample) shipped back to him whenever possible. Dr. Barton had written the first textbook on botany in the United States and was a professor at the University of Pennsylvania. He taught Lewis how to preserve specimens such as plants, birds and animal skins. He advised Lewis on the importance of specimen labels and instructed him how to record the place and date of the collection. Dr. Barton also worked on expanding Lewis’ scientific terminology. Finally, Lewis was advised on what materials to purchase for the preservations of the specimens. Barton was so excited bout the expedition, he even wanted to go along on the trip! However, Barton’s age of thirty-seven prevented his accompanying the expedition. He was too old to undertake such a physically demanding journey. Incidentally, Barton did not donate his textbook for use on the expedition. Lewis had to purchase Barton’s Elements of Botany for $6!

Robert Patterson Patterson was a professor of mathematics at the University of Pennsylvania and the former teacher of Andrew Ellicott. He had authored the book Astronomy Explained upon Sir Isaac Newton’s Principals. Patterson was also considered a navigation expert. It was under Patterson that Lewis received additional lessons in latitude, longitude and navigation that were needed to map the unexplored territory. Patterson was the authority needed to assist Lewis in the selection of the best navigational and measurement instruments available at the time. It was under Patterson’s supervision that Lewis purchased a chronometer from Thomas Parker, a Philadelphia clock and watchmaker. A chronometer is an instrument used to determine accurate measurements of time and critical for the precise measurement of latitude. The chronometer cost $250 and was the single most expensive item purchased for the trip. Lewis then had the instrument shipped to Andrew Ellicott in Lancaster to regulate or tune up.

Caspar Wistar Lewis’ final tutoring session in Philadelphia was with Caspar Wistar, a physician and Professor of Anatomy at the University of Pennsylvania. Wistar authored the first anatomy textbook in America and was a paleontology expert. He was considered the fossil authority of the day. Jefferson and Wistar both believed in the possibility of mastodons, an extinct elephant-like animal, living in the prairies of the unexplored lands. It was under Wistar that Lewis learned how to search for signs of ancient beasts.