At 4 o'clock P. M. we arrived at an old Indian encampment, opposite an island, on which was some wood, and perceiving that none would be met with for many miles a-head, we determined to halt here for the night. The 18th, being Sunday, we remained in camp. This indulgence was not only highly acceptable to the soldiers and men who accompanied us, they being much harassed and fatigued by their exertions during the week, but was necessary for our horses, which, not being in good condition when we left the Missouri, were perceptibly failing under the laborious services they were made to perform. At our nightly encampments we found it necessary to confine them, as we had not always a plentiful supply of grass in the immediate vicinity of our camp, and if left at large they would wander in search of better pasture, and occasion us great trouble to collect them again in the morning. Accordingly, long ropes had been provided, {145} which were carried constantly on the necks of the horses, and by these they were made fast during the night to stakes driven into the ground. After having eaten all the grass within his reach, the horse was removed to another place, and this was done several times during the night, by a guard kept constantly on duty, both for the performance of this service, and also to give timely notice in case of the approach of Indians to the camp. Notwithstanding this care, on our part, our horses were sometimes but poorly fed, as we were often compelled to encamp in places where little grass was to be found. When we remained in camp during the day, they were suffered to range more at liberty, a watch being kept out to prevent their wandering too great a distance. Notwithstanding the sabbath was devoted to the refreshment of our horses, and the relaxation of the men who accompanied us, some attention was given to the great objects of the expedition. Astronomical observations for the correction of our time-piece, and for other purposes, were made. At Engineer Cantonment we had furnished ourselves with portfolios of paper, to receive specimens of such plants as we might collect; but we found that the precautions which had been used to protect these from the weather had been insufficient, some of our collections being in part wet, and others having been made during the heavy rains, which fell before we reached the Pawnee villages, required much attention. The sabbath also afforded us an opportunity to devote a little attention to the important objects of personal cleanliness and comfort. The plain about our encampment was strewed with the bones of the bison, and other animals; and among the rest we distinguished some of men. We picked up a number of human skulls, one of which we thought it no sacrilege to compliment with a place upon one of our pack-horses. Our guides could give us no satisfactory information of the time and manner in which the several persons, {146} to whom these bones formerly belonged, had