Yakut Kumiss Feast (Ysakh Festival), AMNH Anthropology Archives, Neg. No. 1796, taken by Waldemar Jochelson.
"Participants in spring ysakh festivals drank offerings of kumiss, a sacred brew of fermented mare’s milk, from special vessels called choron. Jochelson believed the ritual was dying out, but in modern times ysahk has played a key role in Sakha cultural revival. The ceremony pictured here was held early to accommodate Jochelson's travel schedule." (In Kendall, Laurel, ed. 1997. Drawing Shadows to Stone: The Photography of the Jesup North Pacific Expedition, 1897-1902. New York: American Museum of Natural History, 50).