On the precipitous and almost naked argillaceous hills, which here bound the Missouri valley, we found the oxytropis lambertii, and the great flowering pentstemon; two plants of singular beauty. Here, also, we saw, for the first time, the leafless prenanthes, the yellow euchromia, and many other interesting plants. It would seem that several species of plants are distributed along the course of the Missouri, but do not extend far on either side. Probably the seeds of these have been brought down from their original localities, near the sources of the river. That the distribution of plants is sometimes effected in this way, there can be no doubt, as in the instance of the portulacca, with pilose leaves,[67] and other natives of the high and sandy plains of the Arkansa, which are sometimes found transplanted into the deep forests and fertile soils of the hilly region; but the agency of rivers in this respect appears much less important, than without particular examination, we might be inclined to imagine. In ascending the Missouri, the Arkansa, or any great river, every remove of forty or fifty miles brings the traveller to the locality of some plants, not to be seen below. This is perhaps less the case with rivers running from east to west, or from west to east, than with those whose course in a different direction, traverses several parallels of latitude.
On the 27th, we swam across Mosquito Creek;[68] and after a ride of near thirty miles along the Missouri bottoms, encamped near the mouth of the Boyer,[69] about six miles from the wintering place of the party. Early on the following morning we left our encampment, and were soon after cheered by the report of guns discharging at the Cantonment. The sight of the trading establishment, called Fort Lisa, gave us {111} more pleasure than can easily be imagined, except by those who have made journeys similar to ours, and have felt the deprivation of all those enjoyments which belongs to the habitations of men. At ten a. m. we arrived at the Boyer, which Major Long immediately crossed on a small raft, leaving Captain Bell and Dr. James, with the horses and baggage, to wait until some soldiers could be sent out to assist in crossing. These arrived in a few hours; and before three o'clock we had crossed the Boyer and the Missouri, and found ourselves surrounded by our friends at Engineer Cantonment.
In the early part of June, 1820, arrangements were completed for the departure of the Exploring Expedition from their winter cantonment near Council Bluff. By an order of the Honourable Secretary of War, dated 28th February, Major Long had been instructed to explore the country from the Missouri westward to the Rocky Mountains; and thence, proceeding southward along the base of these mountains to the Arkansa, to despatch a division of his party down that river. The following orders were issued by Major Long, briefly sketching the proposed route, and assigning appropriate duties to each individual of the party.
"Engineer Cantonment, Council Bluff, "Orders. June 1st, 1820.
"Agreeably to the instructions of the Honourable Secretary of War, the further progress of the Exploring Expedition up the Missouri is arrested during the present season. By the same authority, an excursion, by land, to the source of the river Platte, and thence by way of the Arkansa and Red rivers to the Mississippi, is ordered. The expedition will accordingly proceed on this duty as soon as practicable, and be governed by the order of the 31st March, 1819, issued at the United States' arsenal, near Pittsburgh, so far as it may be applicable. The duties therein assigned to Major Biddle will be performed {112} by Captain J. R. Bell, attached to the expedition by order of the war department, with the exception of those parts which relate to the manners, customs, and traditions of the various savage tribes which we may pass. The duties thus excepted will be performed by Mr. Say. The duties assigned to Dr. Baldwin and Mr. Jessup, by the order alluded to, will be performed by Dr. E. James, employed for these purposes, by the sanction of the secretary of war. In these duties are excepted those parts which relate to comparative anatomy, and the diseases, remedies, &c. known amongst the Indians; which will also be performed by Mr. Say.
"Lieutenant Graham will take charge of the United States' steam-boat, Western Engineer, and proceed down the Missouri to the Mississippi, with the remaining part of the crew originally attached to the boat, on the performance of duties assigned him by special order.
"The detachment from the rifle regiment, attached to the expedition, by order from the commanding officer of the 9th military department, will accompany the expedition in their route from this place to Belle Point, on the Arkansa, under the immediate command of Lieutenant Swift, who will inspect daily their arms and accoutrements, and report their condition to the commanding officer. He will receive such instructions from the commanding officer as occasion may require, in relation to the discharge of his duties.
"Guides, interpreters, hunters, and others attached to the expedition, will perform such duties as may be assigned, from time to time, by the commanding officer.
"The duties of the expedition being arduous, and the objects in view difficult of attainment, the hardships and exposures to be encountered requiring zealous and obstinate perseverance, it is confidently expected, that all embarked in the enterprize will {113} contribute every aid in their power, tending to a successful and speedy termination of the contemplated tour.
"S. H. Long, Maj. Engrs.
Commanding Exploring Expedition."