[Clark, July 20, 1804]
July 20th, Friday 1804 a cool morning passed a large willow Island (1) on the S. S. and the mouth of Creek about 25 yds. wide on the L. S. Called by the french l'Eue-que pleure, or the the Water Which Cry's this Creek falls into the river above a Clift of brown Clay opposit the Willow Island, I went out above the mouth of this Creek and walked the greater part of the day thro Plains interspesed with Small Groves of Timber on the branches and Some Scattering trees about the heads of the runs, I Killed a Verry large yellow wolf, The Soil of Those Praries appears rich but much Parched with the frequent fires-" after I returned to the Boat we proceeded around a large Sand bar makeing out from the L. S. opsd. a fountain of water comeing out of a hill L. S. and affording water Suffient to turn a mill
The Praries as far as I was out appeared to be well watered, with Small Streems of running water Serjt. Pryor & Jo. Fields brought in two Deer this evening—a verry Pleasent Breeze from the N. W. all night—river falling a little, It is wothey of observation to mention that our party has been much healthier on the Voyage than parties of the Same Number is in any other Situation Turners have been troublesom to them all
From this evenings incampment a man may walk to the Pane Village on the S bank of the Platt River in two days, and to the Otteaus in one day all those Indians are Situated on the South bank of the Plate River, as those Indians are now out in the praries following & Hunting the buffalow, I fear we will not See them.
[Lewis, July 21, 1804]
July 21, 1804 by a boiling motion or ebolition of it's waters occasioned no doubt by the roling and irregular motion of the sand of which its bed is entirely composed. the particles of this sand being remarkably small and light it is easily boied up and is hurried by this impetuous torrent in large masses from place to place in with irristable forse, collecting and forming sandbars in the course of a few hours which as suddingly disapated to form others and give place perhaps to the deepest channel of the river. where it enters the Missouri it's superior force changes and directs the courant of that river against it's northern bank where it is compressed within a channel less than one third of the width it had just before occupyed. it dose not furnish the missouri with it's colouring matter as has been asserted by some, but it throws into it immence quantities of sand and gives a celerity to it's courant of which it abates but little untill it's junction with the Mississippy. the water of this river is turbid at all seasons of the year but is by no means as much so as that of the Missourie. The sediment it deposits, consists of very fine particles of white sand while that of the Missoury is composed principally of a dark rich loam-in much greater quantity
21st July from the experiments and observations we were enabled to make with rispect to the comparative velocities of the courants of the rivers Mississippi Missouri and Plat it results that a vessel will float in the Mississippi below the entrance of the Missouri at the rate of four miles an hour. in the Missouri from it's junction with the Mississsippi to the entrance of the Osage river from 51/2 to 6 from thence to the mouth of the Kanzas from 61/2 to 7. from thence to the Platte 51/2 while the Plat is at least 8.—The Missouri above the junction of the river plat is equal to about 31/2 miles an hour as far as the mouth of the Chyenne where its courant still abates and becomes equal to about three miles an hour from information it dose not increase it's volocity for