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With Resolute and Thorough Planning: Captain Meriwether
Lewis’ Preparations for the Journey to the Pacific Ocean
By Lieutenant Colonel Mark J. Reardon

The saga of Lewis and Clark is much more than just a dramatic tale of two Army officers who trekked across the American continent. That tale began long before the first step of the journey took place and involved a lengthy period of detailed preparation by the officer in charge, Captain Meriwether Lewis, with the personal support and assistance of the President of the United States, Thomas Jefferson. Lewis had been charged by the President with paving the way westward for the future expansion of the newly independent United States. With little information available for detailed planning, the task before young Captain Lewis was indeed a daunting one. One can only imagine the dozens of issues, both large and small, which occupied Lewis’ thoughts as he prepared to lead a squad of soldiers to the Pacific coast. Since Lewis did not leave extensive notes on his preparations, this process has not previously been discussed in detail.

It was fortunate for Captain Lewis that the President’s vision of westward exploration was based on events spanning a decade or more in the past. President Thomas Jefferson had long possessed a great interest, for both practical and scientific reasons, in exploring the American west. In 1783 he had asked Brigadier General George Rogers Clark to lead an expedition to the Pacific, but Clark refused. Ten years later, Jefferson helped raise money for a westward expedition by botanist Andre Michaux, which was then canceled. In 1801 Jefferson’s interest in exploration was once again awakened by the publication of a book by Alexander MacKenzie in which he chronicled his adventures as the leader of a British expedition searching for a water passage in Canada that stretched from the Atlantic to the Pacific.

With the American Revolution a recent memory, President Jefferson did not want Canadian fur trappers probing deeper and deeper into territory the United States might seek to acquire. Should the British lay formal claim to the Northwest Pacific, the newly independent United States would be hemmed in on virtually all sides by European powers (the Spanish to the south, French to the West, and British to the north and northwest). Additionally, the British would gain exclusive rights to the lucrative fur trapping industry in that region. Confronted by this disturbing specter, President Jefferson summoned Captain Lewis to begin detailed planning for an American expedition to the Pacific.

Jefferson’s choice of Lewis as the leader of an American expedition to the Pacific coast reflects a mix of practicality, common sense, regional alliances, and the turbulent political times in America at the turn of the nineteenth century. Recent British expeditions along the Pacific Coast by Captains James Cook and George Vancouver had convinced Jefferson that modern exploration was best accomplished by combining the resources and talents of both the military and scientific communities. Unlike the British, Jefferson did not choose to rely on the U.S. Navy because he wanted to explore deep into the interior of the North American continent. As a result, the President turned to the U.S. Army.

Captain Meriwether Lewis was a native Virginian whose family was known to Jefferson. Lewis was an ardent political supporter of the President, which was a sought after quality in an Army then known for its political opposition to Jefferson. As for his professional qualifications, Captain Lewis had been a regimental paymaster whose duties took him to many of the frontier posts in the Ohio Valley. Not only did he know the terrain that the expedition would encounter in the initial phase of its journey, but Lewis was also on friendly terms with many of the officers commanding the forts. The deep personal trust that the President had in Lewis’ professional abilities was reflected by Jefferson’s selection of the young officer as his personal military aide. Impressive qualifications aside, planning for a trans-continental expedition would prove to be a daunting task for a “mere” Captain of the First Infantry Regiment.

While his’ burden was somewhat lightened by the President’s involvement and the unflagging support of Secretary of War Henry Dearborn, Lewis knew he would be ultimately held responsible for the success or failure of the expedition. He soon discovered that planning without concrete information certainly did not make matters much easier, despite highly placed supporters. His knowledge of the western expanses of the North American continent was confined to the Ohio River valley. French and Spanish troops prevented him from sending out patrols in advance of the expedition to gather additional intelligence from beyond the Mississippi River. As such, Lewis could not anticipate what he might encounter once the expedition moved west of the supporting chain of American frontier forts. He could only be sure of one thing: there was no way he could summon help. Surrounded by Indians and wild animals, the success of Lewis’ expedition would rest on his ability to predict unforeseen events and plan accordingly.

Intent on discovering a water route to the Pacific that would support commercial traffic, Jefferson and Lewis pored over every piece of published data, to include Jean-Benjamin Francois Dumont de Montigny’s 1728 manuscript “Plan of the Course of the Missouri River”, Antoine Soulard’s “Topographical Sketch of the Upper Mississippi and the Missouri” dated 1795, as well as Nicolas de Finiel’s “Map of a Part of the Course of the Mississippi River” published in 1798. While these works did not form a complete picture of the Pacific Northwest, the documents began to provide Lewis with a rough idea of the best route from the Ohio Valley to a point just east of the modern day Rockies.

Jefferson and Lewis shared the belief that a yet undiscovered water route connecting the East to the West Coast existed. This theory was largely based on a popular scientific notion touting the symmetrical aspect of nature. If the Mississippi River bisected the North American from North to South, then there must be a similar river running lengthwise across the continent. No one knew, however, exactly how wide North America was. Nor was there any reliable hydrological data that could aid the expedition as it traveled by boat from the Ohio Valley to the Pacific Ocean. Additionally, little was known about the characteristics of the terrain bordering the rivers.

Political and logistical factors dictated the size of Lewis’ expedition to the Pacific – in particular, the fact that the French controlled the Louisiana territory, which stretched virtually from British controlled Canada to New Orleans on the Gulf of Mexico. Lewis felt that a small group (15 or less personnel) would have a better chance of getting through undetected by the French than a larger expedition. Because a large group would require a greater amount of supplies. By limiting the number of men that would be accompanying him, Lewis would not have to employ a flotilla of boats to carry supplies, which in turn meant that he would be able to keep his operational “footprint” fairly small.

After much study, Lewis and Jefferson agreed upon a basic concept that broke the expedition into four distinct phases. These phases included initial preparatory efforts in Virginia, Pennsylvania, and Kentucky; a “shakedown” period at an army post in the Illinois Territory during the first winter; movement west to the Pacific in the early spring; and finally the return trip after spending the winter on the Pacific coast. Midway through the expedition, Lewis also planned to send back a detail bearing maps, specimens of newly discovered flora and fauna, and a copy of is scientific observations to date. This prudent measure would not only preclude a worst-case scenario in which all of the data collected by Lewis were lost through an unexpected calamity, but it would also reduce the expedition’s daily supply requirements as it drew even further west of the Mississippi River.

As Lewis completed each preparatory task, he would meet with Jefferson to conduct what would be called in modern terms “an After Action Review”. Based on the President’s feedback, Lewis made adjustments to the draft concept. For example, he originally intended to send the expedition covertly through French Territory. In order to slip through the chain of outposts along the Mississippi, Lewis limited his party to 15 men because they could be carried aboard a single vessel. As the operational concept began to mature, however, the size of the expedition had to be increased to accommodate Jefferson’s desires. Fortunately for the Americans, evolving political events soon permitted the expansion of the expedition. In 1803, Thomas Jefferson successfully concluded the Louisiana Purchase with Napoleon Bonaparte. With this strategic obstacle removed, Lewis was only faced with logistical constraints as he adjusted the plan to account for Jefferson’s evolving requirements.

Most of the changes to the original plan resulted from the fact that the President wanted Lewis to make contact with all of the Indian tribes he encountered along the route to the Pacific. In order to transport sufficient numbers of diplomatic items, such as axes, hatchets, and peace medals, which were intended as gifts from Jefferson to the Indians, Lewis was forced to devote a portion of his available cargo space to gifts at the expense of supplies. He would have to procure larger watercraft to carry all of the necessary cargo. Because few soldiers possessed the skill to handle a boat large enough to transport everything, he had to hire a number of civilian contractors, called “engages”, that possessed suitable experience. Fortunately, Lewis was no longer bound by political restrictions governing the number of men required to make the trek west. However, the expedition would no longer consist solely of uniformed military personnel.

The decision to hire contract boatmen lay in keeping with Lewis’ desire to confine acceptance of volunteers for the expedition to those personnel possessing a required mix of critical skills. Amongst the 32 soldiers and civilians who would eventually make up the permanent party, there were interpreters, hunters, cooks, river men, salt makers, carpenters, blacksmiths, tailors, interpreters and trackers. A carpenter, for example, could hew timber needed to construct a fort, build huts, repair damaged watercraft, construct crude wagons for overland transport of good and boats, and supervise the carving of dugout canoes as necessary. Recognizing that even Lewis lacked depth in certain areas, Jefferson made arrangements for the young Captain to receive additional schooling in botany, natural history, medicine, celestial navigation, map-making and geology from some of the best minds in the American scientific community.

Once the questions of manpower and skill mix were solved, Lewis turned his attention back to gathering supplies and equipment. The city of Pittsburgh would figure prominently in the preparations for the expedition by virtue of the fact that it was a nationally known shipbuilding port located on the Ohio River. Procuring suitable transportation was especially critical since the president had specifically instructed Lewis to find a water route to the Pacific. This meant that one of his first orders of business was to procure a suitable vessel. The ship had to be capable of bearing all of the critical items that the expedition needed, yet would remain light enough to be manhandled over unexpected shallows.

Hoping to test the ability of commercial shipping to navigate the route to the Pacific, Lewis instructed the Pittsburgh shipwright to build a vessel similar to those used to haul goods along the Ohio River. The keelboat design, which was in widespread use at the time as a means of transporting cargo along relatively shallow and calm inland waterways, would measure fifty five feet in length, eight feet four inches in width and fifteen feet high, seemed to fit the bill. The keelboat was a very flexible design in that it could be powered by oars or a sail depending on wind conditions. It also had an artificial keel nailed on to the bottom of the boat to protect it against hull damage from inadvertent grounding. Not only did it represent the most common type of commercial craft being used on inland waterways, but also it was large enough to transport all of the personnel and equipment required by the expedition.

Lewis soon realized, however, that he would be ill advised to rely on making the entire journey aboard the keelboat. Preparing for a worst-case scenario, in which water travel might prove impossible, Lewis also designed an experimental collapsible “steel frame boat” consisting of bolted together steel strips covered with animal skins. This collapsible boat design weighed only 176 pounds (without hides) and could carry up to 8,000 pounds of equipment and personnel. He also purchased two smaller boats, called “pirogues” (one was bought at Pittsburgh and the other at Wheeling, Virginia). Lewis hoped that having a mix of watercraft would give the expedition the flexibility to transfer a portion of its supplies and personnel to smaller vessels should a particular stretch of the river prove too shallow. It would also minimize the possibility that the expedition would have to turn back should one of the watercraft meet with misfortunate.

A quick inspection of the regular Army supply depot at Schuykill Arsenal in Philadelphia served to convince Lewis that most of his equipment needs could not be filled through normal supply channels. The newly constructed arsenal at Harpers Ferry, Virginia, with its skilled crew of artisans, seemed the perfect location to obtain specialized equipment needed for a cross-continent trek. Captain Lewis arrived in Harpers Ferry on March 16, 1803 with a letter from Secretary of War Henry Dearborn addressed to U.S. Armory and Arsenal superintendent Joseph Perkins that read: Sir – You will be pleased to make such arms & iron work, as requested by the Bearer Captain Meriwether Lewis and to have them completed with the least possible delay.

Lewis’ list of requirements included rifles, tomahawks, knives, powder horns, bullet molds, gun slings, fishing hooks, a small grindstone, and the collapsible iron frame boat. Anticipating the need for firearms that could be easily repaired by the members of the expedition rather than a skilled gunsmith, he asked for thirty sets of interchangeable trigger mechanisms and firing locks made from standard patterns for the fifteen Model 1792 pattern rifles he had acquired. This was an unheard of technological development in the United States, where most gunsmiths crafted each weapon in a unique and individual manner.

Lewis also thought of an ingenious solution to the challenge of carrying ammunition and powder aboard the keelboat. Instead of relying on sacks of lead musket balls for his supply of ammunition, Captain Lewis hired a plumber to cast cylindrical lead canisters. Once filled with gunpowder and capped with wax, the canisters proved both waterproof and buoyant. If the keelboat capsized or were sunk, Lewis could count on a readily available supply of bullets and powder. As the need for ammunition arose, the members of the expedition only had to melt the lead canisters into bullet molds to produce more musket balls.

Problems with the construction of the collapsible iron framed boat delayed Lewis’ departure from Harpers Ferry until 18 April 1803. From there he traveled to Philadelphia and Lancaster to attend the specialized scientific instruction previously arranged by the president. While in Philadelphia, Lewis purchased some useful items available only from commercial sources, including 193 pounds of a new type of condensed food known as “portable soup”. Not to be confused with the powdered soup of modern times, this concoction consisted of a glutinous paste of boiled oxtails that had long been a staple of campaigning armies in Europe.

In light of the growing complexity of the mission, Lewis soon realized he would need a second officer with skills that complemented his own. He asked former Army officer and fellow Virginian William Clark to join the expedition as his second-in-command. Clark, who was no longer on active service, possessed considerable combat experience, had traveled widely, and was also well known as a competent cartographer. He readily agreed and was reinstated in the U.S. Army as a Second Lieutenant of Artillery. Despite Lewis’ unsuccessful attempts to have his friend commissioned as a Captain of Infantry, he accorded co-equal status to Clark rather than treating him as a subordinate. Lewis also insisted on addressing Clark as “Captain” and ordered his men to do the same.

Lewis’ efforts to identify and empower proven leaders to assist him was not limited to asking Clark to join as the expedition’s co-commander. Lewis also realized that by carefully choosing the non-commissioned officers he recruited, he would be well served as uncertainty loomed and weather conditions grew harsher during the westward trek. Three sergeants and one corporal were appointed, all of who enjoyed the confidence of their commander. Corporal Richard Warfington, for example, was charged with taking Lewis’ preliminary report, along with journals containing scientific observations, newly sketched maps, and wildlife specimens back to St. Louis aboard the keelboat mid-way through the expedition’s journey.

While Lewis and Clark were busy making last minute arrangements in St. Louis before the expedition departed in May 1804, they left the men in the capable hands of Sergeant John Ordway, who was responsible for maintaining discipline and training the new recruits. The versatility of these men is highlighted by the fact that Ordway, who was in essence the detachment’s first sergeant, also kept a detailed journal during the trek that later provided valuable scientific information. Lewis was obviously a keen judge of men because his non-commissioned officers (NCOs) never failed to accomplish the missions he assigned them, in addition to the daily routine of housekeeping and logistical chores, during the two year, four month, and ten day journey.

The enlisted contingent had been chosen with no less care and attention to detail. Lewis initially enlisted seven privates from Carlisle Barracks, Pennsylvania in August 1803 to assist him in transporting the partially loaded keelboat and pirogues downriver from Pittsburgh to Louisville, Kentucky. Those men returned to Pennsylvania once the watercraft reached their destination. At Louisville, Lewis met William Clark on 14 October 1803, who was accompanied by a number of prospective recruits. Over the next two weeks Lewis and Clark selected nine of the most promising recruits from Kentucky, to include two sergeants, the best hunters (the Field brothers), the salt maker (John Field), and the expedition blacksmith (John Shields).

Armed with Jefferson’s letter permitting him to levy personnel from other Active Army units, Lewis collected the remainder of the enlisted personnel from Forts Massac and Kaskaskia in Illinois, as well as South West Point in Tennessee. These soldiers came from the 1st and 2nd Regiments of Infantry and the Regiment of Artillery. The latter were needed to man the small cannon added to the keelboat by Clark while the expedition wintered at Camp River Dubois, Illinois in 1803 – 04. Most were volunteers, although one or two were detailed to the expedition by their commanders.

The benefits of Lewis’ detailed approach to planning continued even as the expedition waited for spring in its winter quarters at Camp River Dubois. Clark experimented with cross-loading the keelboat and smaller pirogues, juggling the placement of food, equipment, and weapons to minimize loss of critical items in event of the inadvertent loss of one or more watercraft and also to provide for mutual defense should they become temporarily separated. The experiments were also designed to test the stability of the vessels after they were fully loaded. Clark supervised efforts to ensure that the expedition’s arms, ammunition, tools, gifts for Indian chiefs, and critical foodstuffs were shielded by water-resistant material in an effort to minimize potential loss in case of a significant shipboard mishap.

Clark improved upon the defensive capabilities of the keelboat by modifying the lids of on-deck equipment lockers so they could be raised on hinges and fixed in the upright position, which would then provide protection to rifleman firing at an attacking force. Reconfiguration of the expedition’s flagship would provide Lewis with a floating fort capable of protecting the perimeter of the expedition’s daily campsite on the riverbank. For self-defense, a small cannon was mounted on a swivel on the bows, while two blunderbusses (huge shotguns) were positioned on either flank of the stern mounted cabin. On 26 May 1804, the expedition set off on its journey to the sound of cheering crowds lining the banks of the Missouri River. All told, Captain Meriwether Lewis had spent more than a year immersed in the details of planning and preparing for the expedition.


If any nineteenth century scientific expedition ever had an excellent chance of success, this was the one. Mutual respect, trust, and common sense successfully bridged the tremendous gap between the Nation’s Commander in Chief and Captain of Infantry. Originally intended as a “small caravan to go to Louisiana for the advancement of geography”, the expedition continually grew in size and scope. Through it all, Lewis maintained an inherent sense of flexibility and focus that permitted him to successfully make adjustments to account for what would amount to a significant departure from his original mission requirements. It was his meticulous preparations, not a grand sense of adventure, that ultimately ensured the expedition accomplished everything it had been tasked to do and more.

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