As they were now entering a region where foes might be lying in wait on either bank, it was determined, in hunting for game, to confine themselves principally to the islands, which sometimes extend to considerable length, and are beautifully wooded, affording abundant pasturage and shade.  On one of these they killed three buffaloes and two elks, and halting on the edge of a beautiful prairie, made a sumptuous hunter’s repast.  They had not long resumed their boats and pulled along the river banks when they descried a canoe approaching, navigated by two men, whom, to their surprise, they ascertained to be white men.  They proved to be two of those strange and fearless wanderers of the wilderness, the trappers.  Their names were Benjamin Jones and Alexander Carson.  They had been for two years past hunting and trapping near the head of the Missouri, and were thus floating for thousands of miles in a cockle-shell, down a turbulent stream, through regions infested by savage tribes, yet apparently as easy and unconcerned as if navigating securely in the midst of civilization.

The acquisition of two such hardy, experienced, and dauntless hunters was peculiarly desirable at the present moment.  They needed but little persuasion.  The wilderness is the home of the trapper; like the sailor, he cares but little to which point of the compass he steers; and Jones and Carson readily abandoned their voyage to St. Louis, and turned their faces towards the Rocky Mountains and the Pacific.

The two naturalists, Mr. Bradbury and Mr. Nuttall, who had joined the expedition at St. Louis, still accompanied it, and pursued their researches on all occasions.  Mr. Nuttall seems to have been exclusively devoted to his scientific pursuits.  He was a zealous botanist, and all his enthusiasm was awakened at beholding a new world, as it were, opening upon him in the boundless prairies, clad in the vernal and variegated robe of unknown flowers.  Whenever the boats landed at meal times, or for any temporary purpose, he would spring on shore, and set out on a hunt for new specimens.  Every plant or flower of a rare or unknown species was eagerly seized as a prize.  Delighted with the treasures spreading themselves out before him, he went groping and stumbling along among the wilderness of sweets, forgetful of everything but his immediate pursuit, and had often to be sought after when the boats were about to resume their course.  At such times he would be found far off in the prairies, or up the course of some petty stream, laden with plants of all kinds.

The Canadian voyageurs, who are a class of people that know nothing out of their immediate line, and with constitutional levity make a jest of anything they cannot understand, were extremely puzzled by this passion for collecting what they considered mere useless weeds.  When they saw the worthy botanist coming back heavy laden with his specimens, and treasuring them up as carefully as a miser would his hoard, they used to make merry among themselves at his expense, regarding him as some whimsical kind of madman.