This fight took place in the last chapter of Jubal Sackett. LL's note at the end of the book: "According to scholars mammoths died out around 6000 B.C. Nonetheless, American Indians record hunting and killing them. One such report occurs in the Bureau of Ethnology report, The Ponca Tribe...David Thompson, the distinguished Hudson's Bay Co. explorer, on January 7, 1811, came upon some tracks near the Athabasca River in the northern Rockies which the Indians told him were those of a mammoth...