At left is an actual sample collected by Meriwether Lewis. On the right is that sample illustrated in a botany book that chronicled the expedition's findings.

Because Meriwether Lewis’ entire trip to Philadelphia involved preparation, his efforts in the nature field followed that same goal. His time with Benjamin Smith Barton was especially helpful.

Through Barton, Lewis built on the botanical knowledge he already had. Documenting the flora and fauna in the West was of utmost importance. Barton taught Lewis how to preserve specimens, either plant, bird, or animal. He stressed the importance of labeling, including place and date of collection. He also taught Lewis the Linnaean system for classifying specimens with Latin names.

Part of the trip would involve confirming or debunking the mythology of the West. Reports of mammoths and megalonyx still roaming this unexplored region were specific things Lewis planned to investigate.

Of course, the West was an unknown. The biggest tool Lewis would bring was his curious mind and the ability to document the new things he saw. By the end of the journey, his efforts there were an unqualified success.