The Frederic Douglas Ledger was dated to about 1870 by Frederick Dockstader when he examined it in 1979. It consisted of sixty sheets, some of which are now in the collections of the Denver Museum of Natural History and the San Diego Museum of Man. Douglas was the curator of Indian Art at the Denver Art Museum from 1929 until the mid 1950s. He was instrumental in fostering the study and appreciation of Indian art at a time when it had been largely ignored.