In the course of our morning's ride of twenty miles, we saw several gangs of wild horses, and with these we distinguished numbers of colts and some mules. In passing through a village of prairie dogs, of which we saw great numbers, Mr. Peale killed a burrowing owl. The bird, though killed instantly, had fallen into one of the marmot's burrows; but had luckily lodged within the reach of the arm. On opening it, the intestines were found filled with the fragments of grasshoppers' wings, and the hard parts of other insects. We have never been able, from examination, to discover any evidence that these owls prey upon the marmots, whose villages they infest.
After proceeding near twenty miles, we directed our course towards the river, which we kept at some distance on our left; arriving at it at two o'clock, we encamped and sent out the hunters; as we had some hopes of procuring a supply of provisions less repugnant to our prejudices than horse-flesh; the hunters, however, as well as others of the party, spent the remaining part of the afternoon in an unavailing search after game.
The hills which bound the immediate valley of the river at this place, have an elevation of from one to two hundred feet above the surface of the water. They are usually covered with a deep sandy soil, but disclose in their sides, points, and precipices of red sandstone, containing large quantities of very beautiful selenite. The other more common varieties [286] of sulphate of lime are also of frequent occurrence, crystals of carbonate of lime are also met with in veins traversing the sandstone.
The cenchrus tribuloides, a most annoying grass, which is common here, supplies the place of the cactus ferox; and the troublesome stipas of the Platte now become less abundant. The cenchrus bears its seed in small spikelets, which consist of a number of rigid radiating spines. These clusters of barbed thorns are detached at the slightest touch, falling into our mockasins, adhering to our blankets and clothing, and annoying us at every point. The cloth-bur (xanthium strumianum), which had occurred in every part of our route, began now to ripen, and cast off its muricated fruit, adding one more to the sources of constant molestation.
A formidable centipede (scolopendra) was caught near the camp, and brought in alive by one of the engagees. It was about eight inches in length, and nearly three-fourths of an inch in breadth, being of a flattened form, and of a dark brown colour. While kept alive, it showed great viciousness of disposition, biting at every thing which came within its reach. Its bite is said to be venomous.
On the morning of the 8th, we continued our journey, crossing and recrossing the river several times. This we found necessary, as the occurrence of steep and rocky ravines made it impossible to pass along the bank, parallel to the course of the river, which here became more meandering, winding about the points of rocky and impassable promontories.
Few trees occur along this part of the valley; but grape vines were becoming numerous, and some of them loaded with fruit. Among these, we saw numerous signs of the black bear, and one of these animals was this morning seen and shot at, but not killed. We also saw some recent tracks of bison, reviving us with the hope of a return of the days of plenty. We constantly met with the remains of Indian [287] encampments; trees which had been felled with the tomahawk, and other evidences that the country had been recently occupied by savages.
We passed in the afternoon to a more plain and fertile country than that we had been for some days traversing. The river valley became wide, and bounded on both sides by low and rounded hills instead of abrupt and perpendicular precipices. The interior of the country is but little elevated above the river, and its surface is nearly unbroken.
We crossed the beds of several creeks, apparently of large streams in the wet season, but now entirely destitute of water. As yet we had not a single tributary discharging any water into the river, nor had we been able to discover any augmentation of the volume of water, which appeared to have been derived from tributaries entering on the other side. The channels of all the creeks hitherto observed, were beds of sand without water. Several of these "dry rivers," which we passed in the course of the day, have broad valleys, which, if we may judge from a comparison with that we are descending, must have an extent of more than one hundred miles, draining a wide expanse of country of the surplus water in the rainy season, but remaining dry during great part of the year. At five o'clock we encamped, having travelled twenty-six miles due east. The hunters were immediately sent out, but returned without game, having seen nothing.