William Jackson Hooker
It was Hooker who arranged Douglas's first outing as a collector for the London Horticultural Society, and that trip to the eastern United States allowed Douglas to display his talent not only for finding interesting plants, but also for preserving their seeds, slips, and bulbs in ways that would allow them to grow again in Great Britain. After returning to London, the young collector also penned a monograph on American oaks that demonstrated his thorough knowledge of earlier works compiled by André Michaux and Frederick Pursh, and reflected his own thoughts about various oak species for carpentry and shipbuilding.
The Horticulture Society assigned Douglas a far more ambitious undertaking when they booked him passage aboard a Hudson's Bay Company vessel bound for the Columbia River. Before shipping out in late July of 1824, Douglas researched his new collecting territory extensively. He read George Vancouver's account of Great Britain's 1792-96 Pacific Coast surveying expedition, and interviewed Archibald Menzies, who had served as surgeon and naturalist on that trip. Douglas studied Alexander Mackenzie's journey across the Rocky Mountains to the Fraser River and Bella Coola, carried out in 1793 for the North West Fur Company. With a particular eye for natural history, he pored over Nicolas Biddle's published account of the Lewis and Clark Expedition, and procured a copy of Pursh's Flora Americae Septentrionalis, which included taxonomic details of their plant collections, to carry with him for study on the nine-month voyage around Cape Horn.
Title page, Pursh's Flora . . .
With these underpinnings, Douglas recognized landmarks from Vancouver's and William Clark's maps as soon as he sighted Cape Disappointment at the Columbia River's fearsome bar, working his way around Baker Bay, Tongue Point, and Point Adams. The collector continued to name familiar sentinels as he moved inland and viewed the snowcapped volcanoes of the Cascades. "A very conspicuous conical mountain is seen in the dis-tance far exceeding the others in height; this I have no doubt is Mount Jefferson of Lewis and Clarke."4
Within a few days of stepping ashore, Douglas was introduced to the Chinook headman Comcomly, who had known Lewis and Clark well during their winter at Fort Clatsop. In his interactions with the tribal cultures of the lower Columbia, Douglas, again emulating the Corps of Discovery, helped his own cause by quickly learning Chinook jargon, a trade language that allowed him to communicate with tribal and mixed-blood fur trade families throughout that region. Over the course of the next two years, Comcomly's network of kin guided Douglas from Astoria to Grays Harbor, providing him with food, introductions, companionship, deep ethnographic knowledge, and several important collections of flora and fauna. The fact that Douglas collected lower Columbia specimens during all seasons of the year, through several annual cycles, allowed him to expand on the solid base of natural history data begun by Lewis and Clark during their time at Fort Clatsop.
4. David Douglas, Journal Kept by David Douglas, 1823-27, (London: William Wesley & Son, 1914), 106.