previous | next
July 22nd Sunday Set out verry early with a view of getting Some timbered land & a good Situation to take equil altitudes in time proceeded on nearly a North 15° W 〈Course〉 7 ms. to a pt. S. S. opposit Some high Lands on L. S. above the upper point of a long willow Island in the middle of the river 6 Deer killed to Day we deturmined to Stay here 4 or 5 days to take & make obsvts. & refresh our men also to Send Despatches back to govement—  Wind hard N. W. Cold
The Lattitude of River Debous 38° 55' 19" 6/10 N. and Longtd. 89° 57' 45" W of Greenich 
The do—of the gasconade River 38° 44' 35" N. & Longtd about 91° 16' 00' W.
The do of the Great Osage River 38° 31' 6" N. & Longtd. about 91° 38' W.
The do of th mouth of Kansez 39° 5' 25" North
The do of Nordaway river— 39 55 56 do
The do of the Bald pated Prarie 40 27 6 do
The do of Camp above River Plate— 41 3 19 N.
22nd of July 1804 Completlly arranged our Camp, posted two Sentinals So as to Completely guard the Camp, formd bowers for the min &c. &. Course from R Plate N 15° W. 10 Ms.
Set out verry early with a view of Getting to Some Situation above in time to take equal altitudes and take Observations, as well as one Calculated to make our party Comfortabl in a Situation where they Could recive the benifit of a Shade— passed a large Sand bar opposit a Small river on the L. S. at 3 miles above Plate Called Papillion or Butterfly Creek  a Sand bar & an Willow Island opposit a Creek 9 ms. above the Plate on the S. S. Called Mosquitos Creek  Prarie on both Sides of the river. Came too and formed a Camp on the S. S. above a Small Willow Island, and opposit the first Hill which aproach the river on the L. S. and covered with timbers of Oake Walnut Elm &c. &. This being a good Situation and much nearer the Otteaus town than the Mouth of the Platt, we concluded to delay at this place a fiew days and Send for Some of the Chiefs of that nation to let them Know of the Change of Government, The wishes of our Government to Cultivate friendship with them, the Objects of our journy and 〈the〉 to present them with a flag and Some Small presents.
Some of our Provisions in the French Perogue being wet it became necessary to Dry them a fiew days— Wind hard from N W. five Deer Killed to day— The river rise a little
〈Courses〉 Distance of the Missouri and each day assinding—from the mouth to St. Charles
on the Starboard shore above the River Platte, the mouth of which bore S. 15° E. distant 10 miles.—
Observed Equal Altitudes of the with Sext.
Altd. by Sextant at the time of observation 92° 37' —"
Observed Meridian altd. of 's L. L. with Octant by the back Obsetn. 46° 31' —"
Latitude deduced from this obsertn. 41° 3' 19.4"
Observed time and distance of and Antares West, with Sextant.—
A summary discription of the apparatus employed in the following observations; containing also some remarks on the manner in which they have been employed, and the method observed in recording the observations made with them.—
1st— a brass Sextant of 10 Inches radius, graduated to 15' which by the assistance of the nonius was devisible to 15"; and half of this sum by means of the micrometer could readily be distinguished, therefore—7.5" of an angle was perceptible with this instrument: she was also furnished with three eye-pieces, consisting of a hollow tube and two telescopes one of which last reversed the images of observed objects. finding on experiment that the reversing telescope when employed as the eye-piece gave me a more full and perfect image than either of the others, I have most generally imployed it in all the observations made with this instrument; when thus prepared I found from a series of observations that the quantity of her index error was 8' 45" —; this sum is therefore considered as the standing error of the instrument unless otherwise expressly mentioned. the altitudes of all objects, observed as well with this instrument as with the Octant were by means of a reflecting surface; and those stated to have been taken with the sextant are the degrees, minutes, &c shewn by the graduated limb of the instrument at the time of observation and are of course the double altitudes of the objects observed.
2ed— A common Octant of 14 Inches radius, graduated to 20', which by means of the nonius  was devisbile to 1', half of this sum, or 30" was perceptible by means of a micrometer. this instrument was prepared for both the fore and back observation; her error in the fore observation is 2° +, & and in the back observtion 2° 11' 40.3" +
at the time of our departure from the River Dubois untill the present moment, the sun's altitude at noon has been too great to be reached with my sextant, for this purpose I have therefore employed the Octant by the back observation. the degrees ' & " , recorded for ths sun's altitude by the back observation express only the angle given by the graduated limb of the instrument at the time of observation, and are the complyment of the double Altitude of the sun's observed limb; if therefore the angle recorded be taken from 180° the remainder will be the double altitude of the observed object, or that which would be given by the fore observation with a reflecting surface.
3rd— An Artificial Horizon on the construction recommended and practiced by Mr. Andrw. Ellicott of Lancaster, Pensyla., in which water is used as the reflecting surface; believing this artificial Horizon liable to less error than any other in my possession, I have uniformly used it when the object observed was sufficiently bright to reflect a distinct immage; but as much light is lost by reflection from water I found it inconvenient in most cases to take the altitude of the moon with this horizon, and that of a star impracticable with any degree of accuracy.
4th— An Artificial Horizon constructed in the manner recommended by Mr. Patterson of Philadelphia; glass is here used as the reflecting surface. this horizon consists of a glass plane with a single reflecting surface, cemented to the flat side of the larger segment of a wooden ball; adjusted by means of a sperit-level and a triangular stand with a triangular mortice cut through it's center sufficiently large to admit of the wooden ball partially; the stand rests on three screws inserted near it's angles, which serve as feet for it to rest on while they assist also in the adjustment. this horizon I have employed in taking the altitude of the sun when his image he has been reather too dull for a perfect reflection from water; I have used it generally in taking the altitude of the moon, and in some cases of the stars also; it gives the moon's image very perfectly, and when carefully adjusted I consider it as liable to but little error.—
5th— An Artificial Horizon formed of the index specula  of a Sextant cemented to a flat board; adjusted by means of a sperit level and the triangular stand before discribed. as this glass reflects from both surfaces it gives the images of all objects much more bright than either of the other horizons; I have therefore most generally employed it in observing the altitudes of stars—
6th— A Chronometer; her ballance-wheel and [e]scapement were on the most improved construction. she rested on her back, in a small case prepared for her, suspended by an universal joint. she was carefully wound up every day at twelve oclock. Her rate of going as asscertained by a series of observations made by myself for that purpose was found to be 15 Seconds and a 5 tenths of a second too slow in twenty four howers on Mean Solar time. This is nearly the same result as that found by Mr. Andrew Ellicott who was so obliging as to examine her rate of going for the space of fourteen days, in the summer 1803. her rate of going as ascertained by that gentleman was 15.6 s too slow M. T. in 24 h. and that she went from 3 to 4 s. slower the last 12 h, than she did the first 12 h. after being wound up.—
at 12 OCk. on the 14th day of may 1804 (being the day on which the detachment left the mouth of the River Dubois) the Chronometer was too fast M. T. 6 m. 32 s. & 2/10.— This time-piece was regulated on mean time, and the time entered in the following observations is that shewn by her at the place of observation. the day is recconed on Civil time, (i e) commencing at midnight.
7th— A Circumferentor, circle 6 Inches diameter, on the common construction; by means of this instrument adjusted with the sperit level, I have taken the magnetic azimuth of the sun and pole Star. It has also been employed in taking the traverse of the river:— from the courses thus obtained, together with the distance estimated from point to point, the chart of the Missouri has been formed which now accompanys these observations. the several points of observation are marked with a cross of red ink, and numbered in such manner as to correspond with the celestial observations made at those points respectively.
Sunday July 22nd 1804. we Set out eairly to find Some Good Timbered land and a good place to encamp we proceeded on along a high bank S. S. hand some praries along this bank to the hills, which commenced about 10 miles above G. R. Plat. we passed m of a Creek on the N. called Marringua (French) Musquetoe (English) Creek which comes in behind a willow Island. we proceeded on 12 miles from G. R. Plate and encamped  at 11 [10?] oClock on the N. Side of the Missouris at a point convenient for observations & we cleared away the willows & pitched our Tents and built boweries &C.
Sunday July 22d Set out verry erley this morning prossed on in Hopes to find Some wood Land near the mouth of this first mentained River but Could not we prossed on about 10 miles at Lenth found Som on Both Sides of the River encampt on the North Side
Sunday 22nd. We left the river Platte and proceeded early on our voyage, with fair weather. There is high prairie land on the south side, with some timber on the northern parts of the hills. We came nine miles from the mouth of Platte river, and landed on a willow bank. The hunters killed five deer and caught two beaver. 
Sunday July 22d 1804. we Set out eairly to find Some good place for observations &c. for Incamping. we passd. a creek on the N. S. called Musquetoe Creek. came 12 miles & camped. cut & cleaned a place for encamping pitched our tents built bowereys &c,—
Sunday July 22nd This morning we embarked early 〈this morning〉 & proceeded on, in Order to find a place suitable to take an observation, we passed a creek, lying on the North side of the River, called Musketo Creek, we 〈encamped〉 landed, and cleared a place for encamping. we pitched our Tents & built a Bowrey.
The distance we came this day being 12 Miles
1. This July 22 entry is written over this address: Genl. W. Johnston P M. Vincennes Capt. William Clark Saint Louis Attention of Jno. Hay Esqr. Post Mastr. Cahokia IT. (Return to text.)
2. This site, which they called Camp White Catfish, was on the Iowa side, near the Mills-Pottawattamie county line, using the present river course. On the high land on the opposite side is present Bellevue, Sarpy County, Nebraska. This is the first specific mention of plans to send back a party with dispatches for President Jefferson—an intention not actually carried out until April 1805. See Introduction to Volume 2. MRC map 23; MRR map 64. (Return to text.)
3. This calculation is just below Clark's signature:
4. Mileage tables, evidently made at Camp White Catfish, are at right angles to the July 22 entry on this sheet of the Field Notes (document 34). These calculations are overwritten by the mileage table:
5. These positions, presumably written at Camp White Catfish, are above a second entry for July 22, 1804, in the Field Notes, on a different sheet (document 36) from the previous entry. (Return to text.)
6. Biddle apparently placed brackets around the phrase "a large Sand bar . . . Butterfly Creek" and drew a line through it, all in red ink. (Return to text.)
7. In Pottawattamie County, Iowa; still called Mosquito Creek. In 1804 its mouth was probably a few miles farther south, in present Mills County, below Bellevue. Warren map 4; MRC map 23. (Return to text.)
8. Lewis's observation from Codex O. (Return to text.)
9. Lewis's description of astronomical instruments from Codex O. (Return to text.)
10. A nonius is a method for dividing the arc of a circle into a given number of parts. Bedini (TT), 475. (Return to text.)
11. The index specula is simply the mirror from a sextant. Bedini (SILC), 62. (Return to text.)
12. At the party's Camp White Catfish, near Rock Island the Mills–Pottawattamie county line, Iowa. (Return to text.)
13. American beaver, Castor canadensis. (Return to text.)
previous | next