Major John Wesley Powell was a soldier and explorer, a geologist and a professor who led the first government expedition down the Grand Canyon – traveling part of the way in this boat, the Emma Dean.
The boat was named for his wife, who he married while on leave from the army in the middle of the Civil War. After his wedding, he returned to battle, lost part of his right arm, got a promotion, and studied the rocks in the trenches of Gettysburg.
The war ended, he went home and promptly left to go explore the Colorado and Green Rivers, lost some members to either Paiutes or Mormons (they left the group and no one saw them again), and eventually became the second leader of the U.S. Geologic Survey as well as director of the Bureau of Ethnology at the Smithsonian Institution.
Image from the USGS Multimedia Gallery.