Preparations
Meriwether Lewis and William Clark
For years Jefferson had heard of and read accounts of the various ventures of other explorers in parts of the western frontier and consequently had a long held interest in further exploring this largely still unknown region of the continent. In the 1780s, while Minister to France, Jefferson met John Ledyard in Paris and discussed a proposed trip to the Pacific Northwest.[14][15] Jefferson had also read Captain James Cook's A Voyage to the Pacific Ocean (London, 1784), an account of Cook's third voyage, and Le Page du Pratz's The History of Louisiana (London, 1763), all of which greatly influenced his decision to send an expedition. Like Captain Cook, Jefferson also wished to discover a practical route through the Northwest to the Pacific coast. However it was Alexander Mackenzie's Voyages from Montreal (1801), which informed Jefferson (who read the book at Monticello in 1802) of Britain's intent to control the lucrative fur trade of the Columbia River, and convinced him of the importance of securing the territory as soon as possible.[16][17]
Two years into his presidency, Jefferson asked Congress to fund an expedition through the Louisiana Purchase to the Pacific Ocean. He didn't attempt to hide the Lewis and Clark expedition itself from Spanish, French, and British officials but obfuscated his reasons for the venture. He used a secret message to ask for funding due to poor relations with the opposition party in Congress.[18][19][20][21]
In 1803, Jefferson commissioned the Corps of Discovery, and named U.S. Army Captain Meriwether Lewis its leader, who in turn selected William Clark as second in command. Lewis demonstrated remarkable skills and potential as a frontiersman. As the expedition was gaining approval and funding Jefferson made efforts to prepare him for the long journey ahead. [22] Jefferson chose Lewis to lead the expedition rather than a 'qualified scientist' because, "It was impossible to find a character who to a complete science in botany, natural history, mineralogy & astronomy, joined the firmness of constitution & character, prudence, habits adapted to the woods & a familiarity with the Indian manners and character, requisite for this undertaking. All the latter qualifications Capt. Lewis has."
In 1803, Jefferson sent Lewis to study medicinal cures under Benjamin Rush, a physician and humanitarian. Jefferson also arranged for Lewis to be further educated by Andrew Ellicott, an astronomer who instructed him in the use of the sextant and other navigational instruments.[23][24] Lewis however was not ignorant of science and had demonstrated to Jefferson a marked capacity to learn, especially with Jefferson as his teacher. At Monticello Jefferson possessed the largest library in the world on the subject of the geography of the North American continent, and Lewis had full access to that library. Lewis spent time consulting maps and books and conferring with Jefferson at Jefferson's library in Monticello.
Lewis and Clark met near Louisville in October 1803 at the Falls of the Ohio and before departing later in the month, the core "Nine Young Men" were enlisted into the Corps of Discovery.[25][26] Their goals were to explore the vast territory acquired by the Louisiana Purchase and to establish trade and U.S. sovereignty over the native peoples along the River Missouri. Jefferson also wanted to establish a U.S. claim of "Discovery" to the Pacific Northwest and Oregon territory by documenting an American presence there before Europeans could claim the land.[5][27][28][29] According to some historians, Jefferson understood he would have a better claim of ownership to the Pacific Northwest if the team gathered scientific data on animals and plants.[30][31] However his main objectives were centered around finding an all water route to the Pacific coast and commerce. Before their departure Jefferson's instructions to them stated:
"The object of your mission is to explore the Missouri River, & such principle stream of it, as,
by its course and communication with the waters of the Pacific ocean, whether the Columbia,
Oregon, Colorado or any other river may offer the most direct & practicable water communication
across this continent for the purpose of commerce."[32]
The U.S. mint prepared special silver medals with a portrait of Jefferson and inscribed with a message of friendship and peace, called Indian Peace Medals or peace medals. The soldiers were to distribute them to the nations they met. These symbolized U.S. sovereignty over the indigenous inhabitants. The expedition also prepared advanced weapons to display their military firepower. Among these was an air rifle of about .44 caliber, powerful enough to kill a deer.[33][34][35]
The expedition was prepared with sufficient black powder and lead for their flintlock firearms, knives, blacksmithing supplies, and cartography equipment. They also carried flags, gift bundles, medicine and other items they would need for their journey. Much time went into ensuring a sufficient supply of these items.[33][34]
The route of Lewis and Clark's expedition took them up the Missouri River to its headwaters, then on to the Pacific via the Columbia River, and may have been influenced by the purported transcontinental journey of Moncacht-Apé by the same route about a century before. Jefferson had a copy of Le Page's book detailing Moncacht-Apé's itinerary in his library, and Lewis carried a copy with him during the expedition. Le Page's description of Moncacht-Apé's route across the continent, which neglects to mention the need to cross the Rocky Mountains, may be the source of Lewis and Clark's mistaken belief that they could easily carry boats from the Missouri's headwaters to the westward-flowing Columbia.[36]
