Lewis purchased three pocket compasses for $2.50 each and also the compass shown in this picture. The pocket compasses were less cumbersome than the surveyor's compass and were used to take the bearings when impractical to use the circumferentor and when traveling on land. This pocket compass was one of the few items that survived the journey. After the expedition returned to St. Louis, it was purchased by William Clark. The compass is on display at the Smithsonian Institution in Washington, D.C.
