THE EXPEDITION to explore the Louisiana Purchase and the lands beyond, led by Captains Meriwether Lewis and William Clark, is an enduring story of adventure, teamwork, and peerless leadership. The outcome is well known: the loss of only one man over a twenty-eight-month long, eight thousand-mile trek to the Pacific Ocean and back by keelboat, pirogues, horses, and canoes and on foot. The scientific discoveries by Lewis and Clark in the fields of geography, botany, /oology, and ethnology have been justly celebrated: they measured the width of the continent, produced a map considered to be a cartographic masterpiece, and established American claim to Oregon, Washington, and Idaho; they described 178 plants and 122 animals that were new to science, including western signature species such as the ponderosa pine, the prairie dog, the coyote, and the grizzly bear; and they recorded priceless ethnological baseline data of native American cultures, the Shoshoni and Nez Perce among others, that were still untouched by the impending influence, disease, and debasement of Manifest Destiny.
Although the fame of the Lewis and Clark expedition, formally known as the Corps of Volunteers for North-Western Discovery, comfortably rests on the aforementioned achievements and the vivid images of an untouched, and now largely vanished, wilderness, what about geology? That geology was an important aspect of the expedition goals is irrefutable, because the task of documenting the "mineral productions of every kind" was included in President Thomas Jefferson's preexpeditionary instructions and was slated to be an essential part of the postexpeditionary second volume of the never-completed Conrad and Company edition of the journals. Why did Jefferson have mineralogy included in the expedition instructions? What role did Jefferson and other members of the American Philosophical Society (APS) play in Lewis's, and by extension dark's, geological education and their use of appropriate scientific terminology? What did Lewis and Clark, the first American explorers of the West, emphasize in their journal observations and why? Are there useful, perhaps even insightful, observations of geology in the captains'journals, safeguarded by APS for nearly two hundred years, that have gone unappreciated by historians and scientists alike? And have Lewis and Clark been judged fairly by historians with regard to their geological and mineralogical observations, given the state of these sciences at the dawn of the nineteenth century?
MINERALOGY, GEOLOGY, AND THOMAS JEFFERSON'S "INSTRUCTIONS TO LEWIS"
Consistent with his Enlightenment ideals that science should be applied to serve mankind in order to further progress and ensure human happiness, Thomas Jefferson undoubtedly viewed the natural productions of the land as one of the most essential elements of this philosophy.' While it has been recognized that climate, soils, flora, and fauna were of principal interest to Jefferson, it bears noting that Jefferson never failed to have mineralogy included in any set of instructions he developed for exploration of the trans-Mississippi West. There is also much evidence that Jefferson had been thinking about geological concepts and the vast mineral potential of the new nation in the decades that preceded the Lewis and Clark expedition.
In a handful of Jefferson's prodigious correspondence, minerals appear to have been an ephemeral curio that Jefferson enjoyed sharing with his contemporaries, particularly his friends in Europe. Desiring to obtain specimens prior to his impending voyage to Europe to begin his tenure as minister plenipotentiary to France, Jefferson enlisted the assistance of George Rogers Clark in his November 26, 1782, letter to provide "[descriptions of animals, vegetables, minerals, or other curious things."2 Fourteen years later, Jefferson found himself facilitating the exchange of mineral specimens, among other natural history items, with Prince Louis, heir to the Spanish throne, who was creating a personal "cabinet," or museum. …