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A L E T T E R T O M E R I W E T H E R L E W I S

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–––––––––––––––––––––– Thomas Jefferson –––––––––––––––––––––

20 June 1803

To Captain Meriwether Lewis esq. Capt. of the 1st regimt. of Infantry of the

U.S. of A.

Your situation as Secretary of the President of the U.S. has made you

acquainted with the objects of my confidential message of Jan. 18, 1803 to the

legislature; you have seen the act they passed, which, tho’ expressed in general

terms, was meant to sanction those objects, and you are appointed to carry

them into execution.

Instruments for ascertaining, by celestial observations, the geography of the

country through which you will pass, have been already provided. Light articles

for barter and presents among the Indians, arms for your attendants, say for

from 10. to 12. men, boats, tents, & other travelling apparatus, with

ammunition, medecine, surgical instruments and provisions you will have

prepared with such aids as the Secretary at War can yield in his department; &

from him also you will recieve authority to engage among our troops, by

voluntary agreement, the number of attendants above mentioned, over whom

you, as their commanding officer, are invested with all the powers the laws give

in such a case.

As your movements while within the limits of the U.S. will be better directed

by occasional communications, adapted to circumstances as they arise, they

will not be noticed here. What follows will respect your proceedings after your

departure from the United states

Your mission has been communicated to the ministers here from France,

Spain & Great Britain, and through them to their governments; & such

assurances given them as to it’s objects, as we trust will satisfy them. The

country <of Louisiana > having been ceded by Spain to France, <and possession

by this time probably given,> the passport you have from the minister of France,

the representative of the present sovereign of the country, will be a protection

with all it’s subjects; & that from the minister of England will entitle you to the

friendly aid of any traders of that allegiance with whom you may happen to

meet.

The object of your mission is to explore the Missouri river, & such principal

stream of it, as, by it’s course and communication with the waters of the Pacific

ocean, whether the Columbia, Oregan, Colorado or any other river may offer

the most direct & practicable water communication across this continent for

the purposes of commerce.

Beginning at the mouth of the Missouri, you will take <careful> observations

of latitude & longitude, at all remarkeable points on the river, & especially at

the mouths of rivers, at rapids, at islands, & other places & objects

distinguished by such natural marks & characters of a durable kind, as that they

may with certainty be recognised hereafter. The courses of the river between

these points of observation may be supplied by the compass the log-line & by

time, corrected by the observations themselves. The variations of the compass

too, in different places, should be noticed.

The interesting points of the portage between the heads of the Missouri, & of

the water offering the best communication with the Pacific ocean, should also

be fixed by observation, & the course of that water to the ocean, in the same

manner as that of the Missouri.

Your observations are to be taken with great pains & accuracy, to be entered

distinctly & intelligibly for others as well as yourself, to comprehend all the

elements necessary, with the aid of the usual tables, to fix the latitude and

longitude of the places at which they were taken, and are to be rendered to the

war-office, for the purpose of having the calculations made concurrently by

proper persons within the U.S. Several copies of these as well as of your other

notes should be made at leisure times, & put into the care of the most trustworthy

of your attendants, to guard, by multiplying them, against the accidental

losses to which they will be exposed. A further guard would be that one of

these copies be on the paper of the birch, as less liable to injury from damp than

common paper.

The commerce which may be carried on with the people inhabiting the line

you will pursue, renders a knolege of those people important. You will

therefore endeavor to make yourself acquainted, as far as a diligent pursuit of

your journey shall admit, with the names of the nations & their numbers;

the extent & limits of their possessions;

their relations with other tribes of nations;

their language, traditions, monuments;

their ordinary occupations in agriculture, fishing, hunting, war, arts, & the

implements for these;

their food, clothing, & domestic accomodations;

the diseases prevalent among them, & the remedies they use;

moral & physical circumstances which distinguish them from the tribes we

know;

peculiarities in their laws, customs & dispositions;

and articles of commerce they may need or furnish, & to what extent.

And, considering the interest which every nation has in extending &

strengthening the authority of reason & justice among the people around them,

it will be useful to acquire what knolege you can of the state of morality,

religion, & information among them; as it may better enable those who may

endeavor to civilize & instruct them, to adapt their measures to the existing

notions & practices of those on whom they are to operate.

Other objects worthy of notice will be the soil & face of the country, it’s

growth & vegetable productions, especially those not of the U.S.

the animals of the country generally, & especially those not known in the

U.S.

the remains or accounts of any which may be deemed rare or extinct;

the mineral productions of every kind; but more particularly metals,

limestone, pit coal, & saltpetre; salines & mineral waters, noting the

temperature of the last, & such circumstances as may indicate their

character;

volcanic appearances;

climate, as characterised by the thermometer, by the proportion of rainy,

cloudy, & clear days, by lightning, hail, snow, ice, by the access & recess

of frost, by the winds prevailing at different seasons, the dates at which

particular plants put forth or lose their flower, or leaf, times of appearance

of particular birds, reptiles or insects.…

In all your intercourse with the natives, treat them in the most friendly &

conciliatory manner which their own conduct will admit; allay all jealousies as

to the object of your journey, satisfy them of it’s innocence, make them

acquainted with the position, extent, character, peaceable & commercial

dispositions of the U.S.[,] of our wish to be neighborly, friendly & useful to

them, & of our dispositions to a commercial intercourse with them; confer with

them on the points most convenient as mutual emporiums, and the articles of

most desireable interchange for them & us. If a few of their influential chiefs,

within practicable distance, wish to visit us, arrange such a visit with them, and

furnish them with authority to call on our officers, on their entering the U.S. to

have them conveyed to this place at the public expence. If any of them should

wish to have some of their young people brought up with us, & taught such arts

as may be useful to them, we will receive, instruct & take care of them. Such a

mission, whether of influential chiefs or of young people, would give some

security to your own party. Carry with you some matter of the kinepox; inform

those of them with whom you may be, of it’s efficacy as a preservative from the

smallpox; & instruct & encourage them in the use of it. This may be especially

done wherever you winter.

As it is impossible for us to foresee in what manner you will be recieved by

those people, whether with hospitality or hostility, so is it impossible to

prescribe the exact degree of perseverance with which you are to pursue your

journey. We value too much the lives of citizens to offer them to probable

destruction. Your numbers will be sufficient to secure you against the

unauthorised opposition of individuals or of small parties; but if a superior

force, authorised, or not authorised, by a nation, should be arrayed against your

further passage, and inflexibly determined to arrest it, you must decline it’s

farther pursuit, and return. In the loss of yourselves, we should lose also the

information you will have acquired. By returning safely with that, you may

enable us to renew the essay with better calculated means. To your own

discretion therefore must be left the degree of danger you may risk, and the

point at which you should decline, only saying we wish you to err on the side of

your safety, and to bring back your party safe even if it be with less

information.…

On your arrival on that coast endeavor to learn if there be any port within

your reach frequented by the sea-vessels of any nation, & to send two of your

trusty people back by sea, in such way as <they shall judge> shall appear

practicable, with a copy of your notes: and should you be of opinion that the

return of your party by the way they went will be eminently dangerous, then

ship the whole, & return by sea, by the way either of cape Horn, or the cape of

good Hope, as you shall be able. As you will be without money, clothes or

provisions, you must endeavor to use the credit of the U.S. to obtain them, for

which purpose open letters of credit shall be furnished you, authorising you to

draw upon the Executive of the U.S. or any of it’s officers, in any part of the

world, on which draughts can be disposed of, & to apply with our

recommendations to the Consuls, agents, merchants, or citizens of any nation

with which we have intercourse, assuring them, in our name, that any aids they

may furnish you, shall be honorably repaid, and on demand.…

Should you find it safe to return by the way you go, after sending two of your

party round by sea, or with your whole party, if no conveyance by sea can be

found, do so; making such observations on your return, as may serve to supply,

correct or confirm those made on your outward journey.

On re-entering the U.S. and reaching a place of safety, discharge any of your

attendants who may desire & deserve it, procuring for them immediate paiment

of all arrears of pay & cloathing which may have incurred since their departure,

and assure them that they shall be recommended to the liberality of the

legislature for the grant of a souldier’s portion of land each, as proposed in my

message to Congress: & repair yourself with your papers to the seat of

government <to which I have only to add my sincere prayer for your safe

return>.

To provide, on the accident of your death, against anarchy, dispersion, & the

consequent danger to your party, and total failure of the enterprize, you are

hereby authorised, by any instrument signed & written in your own hand, to

name the person among them who shall succeed to the command on your

decease, and by like instruments to change the nomination from time to time as

further experience of the characters accompanying you shall point out superior

fitness: and all the powers and authorities given to yourself are, in the event of

your death, transferred to, & vested in the successor so named, with further

power to him, and his successors in like manner to name each his successor,

who, on the death of his predecessor, shall be invested with all the powers &

authorities given to yourself.

Given under my hand at the city of Washington this 20th day of June 1803.