Less well known than the vivid description by Ferris but even more remarkable is his “Map of the Northwest Fur Country,” drawn in 1836. Lying in the family trunk for over a century, unknown to geographers and historians, it was made available in 1940 for publication with the journals. This is, to quote Dr. Phillips, “the most detailed and accurate of all the early maps of the region,” far superior in accuracy to the famous maps by Bonneville, Parker, John C. Fremont, and others which were published contemporaneously. In addition to mountain chains, valleys, and trails, it locates such fascinating details as “Yellow stone L.,” “Boiling water,” and “Volcanoes” near the south shore of the lake and “spouting fountains” within the “Burnt Hole” at the head of Madison River, indicating the present West Thumb thermal area and the Upper Geyser Basin on Firehole River, respectively. The context of the journal, together with the evidence of the map, suggests that Ferris beheld and described Old Faithful, the geyser which has become the symbol of Yellowstone National Park. In August of 1834 a party of fifty-five men in Bonneville’s employ led by Joseph H. Walker ascended Pacific Creek from Jackson’s Hole and after some debate “agreed to move down onto Wind River,” instead of descending the Yellowstone. Thus Walker, who had previously discovered Yosemite Valley, and Zenas Leonard, the journalist of the expedition, missed the big exploring opportunity which Ferris had grasped. The quaint nomenclature bestowed on certain locales and landmarks by the mountain trappers offer more than one clue to their shadowy passage. The Gardner River Valley at Swan Lake Flats, between Mammoth Hot Springs and Obsidian Cliff, seems to be the most likely locale of the beaver-rich “Gardner’s Hole” frequented by the mountain men, probably named for Johnson Gardner, a freelance trapper who must have frequented those parts at least as early as 1834, possibly as early as 1830 as Chittenden suggests. His name appears in the Fort Union account books of 1832, which include an agreement to purchase his stock of beaver skins then cached on Yellowstone River. In 1834 he fell in with Prince Maximilian of Wied on the Lower Missouri, revealing to that distinguished traveler that “he was on his return from hunting beavers on the Upper Yelowstone.”