Divide
and emptying into the Missouri. Captain Lewis accordingly left the
party, with four men, and struck off across the country in search of
the stream. Under the next day's date the journal reports the return of
Captain Lewis and says:--

"On leaving us yesterday he pursued his route along the foot of the
hills, which he descended to the distance of eight miles; from these
the wide plains watered by the Missouri and the Yellowstone spread
themselves before the eye, occasionally varied with the wood of the
banks, enlivened by the irregular windings of the two rivers, and
animated by vast herds of buffalo, deer, elk, and antelope. The
confluence of the two rivers was concealed by the wood, but the
Yellowstone itself was only two miles distant, to the south. He
therefore descended the hills and camped on the bank of the river,
having killed, as he crossed the plain, four buffaloes; the deer alone
are shy and retire to the woods, but the elk, antelope, and buffalo
suffered him to approach them without alarm, and often followed him
quietly for some distance."

The famous water-course, first described by Lewis and Clark, was named
by them the Yellow Stone River. Earlier than this, however, the French
voyageurs had called the Upper Missouri the Riviere Jaune, or Yellow
River; but it is certain that the stream, which rises in the Yellowstone
National Park, was discovered and named by Lewis and Clark. One of the
party, Private Joseph Fields, was the first white man who ever ascended
the Yellowstone for any considerable distance. Sent up the river by
Captains Lewis and Clark, he travelled about eight miles, and observed
the currents and sand-bars. Leaving the mouth of the river, the party
went on their course along the Missouri. The journal, under date of
April 27, says:--

"From the point of junction a wood occupies the space between the two
rivers, which at the distance of a mile come within two hundred and
fifty yards of each other. There a beautiful low plain commences,
widening as the rivers recede, and extends along each of them for
several miles, rising about half a mile from the Missouri into a plain
twelve feet higher than itself. The low plain is a few inches above high
water mark, and where it joins the higher plain there is a channel of
sixty or seventy yards in width, through which a part of the Missouri,
when at its greatest height, passes into the Yellowstone. . . .

"The northwest wind rose so high at elev