Photo outfit at the summit of Mount Washburn. Yellowstone National Park, Wyoming. circa 1871.

Album caption and index card: Photo outfit at the summit of Mt. Washburn. [Yellowstone National Park] Wyoming. n.d. Handwritten note on album caption: 1883 Typed information on back of duplicate photograph: One of Jackson's assistants holds Hypo, the aptly-named mule, who at times, carried as much as 350 pounds of photo equipment. On summit of Mount Washburn, Yellowstone area, Wyoming Territory. Year: 1874. Photo by W.H. Jackson. Neg. no. 57-HS-711 in the National Archives. Published on page 30, lower left photograph, of the USGS GIP, Ferdinand Vandiveer Hayden and the Founding of the Yellowstone National Park. Personal email communication from Alan Terrell on January 23, 2021, "The date is likely 1871 since that is the only [...]