Photo: Boulder-White Cloud Mountains, courtesy Craig Gehrke.

August 23, 1805. Clark: The River from the place I left my party to this Creek is almost one continued rapid, five verry considerable rapids     the passage of either with Canoes is entirely impossible, as the water is Confined between huge Rocks & the Current beeting from one against another for Some distance below &c. &c.     at one of those rapids the mountains close so Clost as to prevent a possibility of a portage with [out] great labour in cutting down the Side of the hill removeing large rocks &c. &c.     all the other may be passed by takeing every thing over slipery rocks, and the Smaller ones Passed by letting down the Canoes empty with Cords, as running them would certainly be productive of the loss of Some Canoes, those dificulties and necessary precautions would delay us an emence time in which provisions would be necessary.