Our course was a little to the east of south, nearly at right angles to the direction of the Arkansa. It was our intention to cross to and ascend the First Fork, a considerable stream, entering the Arkansa eighteen miles below our last encampment. After leaving the river we found the surface to rise gradually till, at the distance of six or eight miles, it is broken by a few small gravelly ridges. These are of little elevation; and their summits overlook an extensive waste of sand, terminated towards the south and east only by the verge of the sky, on the west and north-west by the snowy summits of the Spanish mountains. As our way led across the general course of the stream, we met with no water, except such as was still standing in puddles, which had been filled by the last night's rain. Near one of these we halted to dine. The thermometer, hanging in the shade of our tent, the most perfect, and indeed the only shade we could find, stood at 100°. The little water we could procure was thick with mud, and swarming with the larva of mosquitos; but this we regretted the less, as we had no cooking to perform. We dined upon jerked meat from our packs. Some animals, seen at a distance, [256] were at first mistaken for bisons; but were found, by the hunters sent in pursuit of them, to be horses, and too wild and vigilant to be taken.
A species of cone-flower (rudbeckia tagetes)[42] with an elongated receptacle, and large red brown radial florets, was observed about the margin of the stagnant pool near which we halted.
We also collected the linum rigidum, and a semi-procumbent species of sida, which appears to be undescribed. It is a little larger than the S. spinosa, to which it has some general resemblance.
The whole tract passed in this day's journey of twenty-seven miles, is sterile and sandy. At sunset we were so fortunate as to meet with another small pool of water, by which we pitched our tent, and kindled a fire with the dung of the bison. Since leaving the Arkansa, we had scarcely seen so much wood as, if collected, would have supplied us for a single night.
We passed, in the course of the day, not less than four or five paths, leading south-west, towards the Spanish settlements. Some of them appeared to have been recently travelled by men with horses, such paths being easily distinguished from those of bisons or wild horses.[43]
Our camp was near the head of a dry ravine, communicating to the south-east, with a considerable stream, which we could distinguish at the distance of eight or ten miles, by a few trees along its course.[44] Continuing our journey on the ensuing day, July 25th, we soon found ourselves in a tract of country resembling that on the Arkansa near the mountains. A similar horizontal slaty sandstone occurs, forming the basis of the country. There is also here a coarse, somewhat crystalline, variety, resembling that of St. Michael's in the lead mine district, but exhibiting no trace of metallic ores. These rocks are deeply channeled by the watercourses, sunk to a great depth, but at this time containing but little, if any, [257] water. These ravines are, the greater number of them, destitute of timber, except a few cedars, attached here and there in the crevices of the rock. The larger valleys, which contain streams of water, have a few cotton-wood and willow trees. The box elder, the common elder, (sambucus canadensis,) and one or two species of biburium are seen here.
It was perhaps owing to our having followed more carefully than they deserved, the directions of the Calf, that we did not arrive as early as we had expected, upon the stream we designed to ascend. In the middle of the day on the 25th, we fell in with a small river, at the distance of thirty-six miles from the point where we had left the Arkansa. This we concluded could be no other than that tributary, whose mouth is said to be distant eighteen miles from the same spot. This stream, where we halted upon it to dine, is about ten yards wide and three feet deep, but appeared at this time unusually swollen. Its immediate valley is about three hundred yards in width, bounded on both sides by perpendicular cliffs of sandstone, of near two hundred feet elevation. A very large part of the area included between these, showed convincing evidence, in the slime and rubbish with which its surface was covered, of having been recently inundated. This stream, like all others of similar magnitude, having their sources in high mountains, is subject to great and sudden floods. A short time before we halted, our two hunters, Verplank and Dougherty, were sent forward to hunt, and joined us with a deer soon after we had encamped.
After dinner we moved on, ascending the creek above mentioned, whose valley was sufficiently wide for a little distance, to afford us an easy and unobstructed passage. The stream runs nearly from south to north, in a deep, but narrow and tortuous valley, terminated on both sides by lofty and perpendicular precipices of red sand rock. This sandstone [258] appears entirely to resemble that before mentioned, as occurring in an inclined position along the base of the mountains, on the Arkansa and Boiling-spring creek. Here it is disposed in horizontal strata of immense thickness; it varies in colour, from a bright brick red to a dark, and is sometimes grey, yellow, or white. It consists essentially of rounded particles of quartz and other siliceous stones, varying in size from the finest sand to gravel stones and large pebbles. Extensive beds of pudding-stone occur in every part of it, but are abundant somewhat in proportion to the proximity of the high primitive mountains. In the lower parts of the stratum these beds of coarse conglomerate appear to have the constituent gravel and pebble-stones more loosely cemented than in portions nearer to the upper surface; wherever we have met with them in immediate contact with the granite of the Rocky Mountains, they are nearly destitute of cement, and of a colour approaching to white. This remark, it is highly probable, may not be applicable to many extensive beds of pudding-stone which lie near the base of the mountains. In the instances which came under our notice, the absence of colour and the want of cement may very probably have been accidental. The finer varieties of the sandstone are often met with in the immediate neighbourhood of the granite, and are of a compact structure, and an intense colour. Red is the prevailing colour in every part of the stratum, but stripes of yellow, grey, and white, are frequently interspersed. In hardness and other sensible properties, it varies widely at different points. In many instances it is entirely similar to the sandstone about New Brunswick, in New Jersey, at Nyac, and along the Tappan bay, in New York, and particularly that variety of it which is quarried at Nyac, and extensively used in the cities of New York and Albany for building. It contains a little mica in small scales; oxyde of iron predominates in the cement, and the ore denominated [259] the brown oxyde, occurs in it in seniform botryoidar and irregular masses.
A few miles above our mid-day encampment, we entered the valley of a small creek, tributary from the south-east to the stream we had been ascending; but this we found so narrow and so obstructed by fallen masses of rock, and almost impenetrable thickets of alders and willows, as to render our progress extremely tedious and painful. We were several times induced to attempt passing along the bed of the stream, but as the mud was in many places very deep, this was done at the cost of the most violent and fatiguing exertions on the part of our horses, and the risk to ourselves of being thrown with our baggage into the stream. With the hope of finding an easier route across the hills, we ascended with much difficulty a craggy and abrupt ravine, until we had attained nearly the elevation of the precipitous ramparts which hemmed in the narrow valley of the creek; but all we gained by this ascent was the opportunity of looking down upon a few of our companions still lingering below, diminished to the stature of dwarfs by the distance, and by contrast with the rude and colossal features of the scene. The surface of the country extending on both sides from the summit of the precipices, consisted of abrupt conic piles, narrow ridges, and shapeless fragments of naked rocks, more impassable than the valley below. Counselled therefore by necessity, we resumed our former course, ascending along the bed of the creek.[45]
Among other birds which occurred in this day's march, we noticed the yellow-bellied fly catcher and the obscure wren.