By mid-July 1805, the corps was desperate to acquire horses—and information—from the Shoshone, the tribe, also known as the Snake Indians, from which interpreter Sacagawea had been abducted five years before. The captains decided that the company might be taken for a raiding party by any Shoshone in the area, so it was agreed that Clark would go ahead with a smaller, less threatening group.
July 18, 1805 [Capt. Meriwether Lewis]
As we were anxious now to meet with the [Shoshone] or snake Indians as soon as possible in order to obtain information relative to the geography of the country and also if necessary, some horses we thought it better for one of us either Capt. C. or myself to take a small party & proceed on up the river, some distance before the canoes, in order to discover them, should they be on the river before the daily discharge of our guns, which was necessary in procuring subsistence for the party, should allarm and cause them to retreat to the mountains and conceal themselves, supposing us to be their enemies who visit them usually by the way of this river.
July 22 [Lewis]
We set out early as usual. The river being divided into such a number of channels by both large and small Island that I found it impossible to lay it down correctly.... The Indian woman recognizes the country and assures us that this is the river on which her relations live, and that the three forks are at no great distance. [This] peice of information has cheered the sperits of the party who now begin to console themselves with the anticipation of shortly seeing the head of the missouri yet unknown to the civilized world.
July 27 [Lewis]
We begin to feel considerable anxiety with rispect to the Snake Indians. [If] we do not find them or some other nation who have horses I fear the successfull issue of our voyage will be very doubtfull or at all events much more difficult in it’s accomplishment. [We] are now several hundred miles within the bosom of this wild and mountanous country, where game may rationally be expected shortly to become scarce and subsistence precarious....
July 28 [Lewis]
I dispatched two men early this morning up the S.E. Fork to examine the river.... Both Capt. C. and myself...agreed to name [the three streams] after the President of the United States and the Secretaries of the Treasury and state.... Our present camp is precisely on the spot that the Snake Indians were encamped at the time the Minnetares of the Knife R. first came in sight of them five years since. [From] hence they retreated about three miles up Jeffersons river and concealed themselves in the woods, the Minnetares pursued, attacked them, killed 4 men 4 women a number of boys, and mad prisoners of all the females and four boys, Sah-cah-gar-we-ah [our] Indian woman was one of the female prisoners taken at that time; tho’ I cannot discover that she shews any immotion of sorrow in recollecting this event, or of joy in being again restored to her native country; if she has enough to eat and a few trinkets to wear I beleive she would be perfectly content anywhere.