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from the western mountain, estimated to be of equal height with that from which the hot springs flow, there are several fine prospects. The valley of the Washita, comprehended between the hills on either side seemed to be a perfect flat, and about twelve miles wide. On all hands were seen the hills, or mountains, as they are here called, rising behind each other. In the direction of north, the most distant were estimated to be fifty miles off, and are supposed to be those of the Arkansa river, or the rug£ed mountains which divide the waters of the Arkansa from those of the Washita, and prevent the Osoge Indians from visiting the latter, of whom they are supposed ignorant, otherwise their excursions here would prevent this place from being visited by white persons, or other Indians. In a . south west direction, at about forty miles distance, is seen a perfectly level ridge, supposed to be the high prairies of the Red river. Notwithstanding the severity of the weather, a considerable number, and some variety of plants were in flower, and others retained their verdure : indeed the ridge was more temporate than the valley below ; there it was cold, damp, and penetrating ; here dry, and the atmosphere mild. Of the plants growing here was a species of cabbage: the plants grow with expanded leaves spreading on the ground, of a deep green, with a shade of purple : . the taste of the cabbage was plainly predominant, with an agreeable warmth, inclining to that of the radish ; several tap-roots penetrated into the soil, of a white colour, having the taste of horse-radish, but much milder. A quan-, tity of them taken to the camp and dressed, proved pal: table and mild. It, is not probable that cabbage seed has been scattered on this ridge ; the hun-, ters ascending this river have always had different objects. Until further, elucidation, this cabbage must be considered as indigenous to this sequestered quarter, and may be denominated the cabbage radish of the Washita. They found a plant, then green, called by the French “racine rouge,” (red root), which is said to be a specifick in female obstructions ; it has also been used, combined with the China root, to dye red, the last probably acting as a mordant. The top of this ridge is covered with rocks of a flinty kind, and so very hard as to be improper for gun-flints, for when applied to that use it soon digs cavities in the hammer of the lock. This hard stone is generally white, but frequently clouded with red, brown, black, and other co-. lours. Here and there fragments of iron stone were met with, and where. a tree had been overturned, its roots brought to view frigments of schistus, which were suffering decomposition from exposure to the atmosphere. On digging where the slope of the hill was precipitous, they found the second stratum to be a reddish clay, resembling that found on the conical hill, east of the camp. At two-thirds down the hill, the rock was a hard freestone, . intermixed with fragments of flint, which had probably rolled from above. Still lower was found a blue schistus, in a state tending to decomposition. where exposed to the atmosphere, but hard and resembling coarse slate in. the interiour. Many stones had the appearance of Turkey oil stones: at the foot of the hill it expands into good farming lands. Dr. Henter, upon examining the waters of the hot springs, obtained the . following results : - It differed nothing from the hot water in smell or taste, but caused a slight eructation shortly after drinking it. Its specifick gravity is equal to rain or distilled water. . . It gave to litamus paper, a slight degree of redness, evincing the presence of the carbonick acid, or fixed air sulphurick, and threw down a few detached particles. Oxylat of ammoniack caused a deposition and white cloud, she w-. . into the presence of a small portion of lime. Prusiat of potash produced a slight and scarcely perceptible tinge of blue, designating the presence of a small quantity of iron. Wol. III. Appendix. L

Sixteen pounds of water, evaporated to dryness, left ten grains of a grey powder, which proved to be lime. The myrtle wax tree grows in the vicinity of the springs. At the season in which the voyagers were there, the wax was no longer green, but had changed its colour to a greyish-white, from its long exposure to the weather. The berry, when examined by the microscope, is less than the smallest garden pea, approaching to an oval in form. The nuclus, or real seed, is the size of the seed of a radish, and is covered with a number of kidney shaped glands, of a brown colour and sweet taste ; these glands secrete the wax which completely envelopes them, and, at this season, gives to the whole the appearance of an imperfectly white berry. This is a valuable plant and merits attention : its favourite position is a dry soil, rather poor, and looking down upon the water. It is well adapted to ornament the margins of canals, lakes, or rivulets. The cassina yapon is equally beautiful, and proper for the same purpose : it grows here along the banks of this stony creek, intermingled with the myrtle, and bears a beautiful little red berry, very much resembling the red currant. The rock, through which the hot springs either pass or trickle over, appears undermined by the waters of the creek. The hot water is continually depositing calcareous, and, perhaps, some silicious matter, forming new rocks, always augmenting and projecting their promontories over the running water of the creek, which prevents its formation below the surface. Wherever this calcareous crust is seen spreading over the bank and margin of the creek, there, most certainly, the hot water will be found, either running over the surface, or through some channel, perhaps below the new rock, or dripping from the edges of the overhanging precipice. The progress of nature in the formation of this new rock is curious and worthy the attention of the mineralogist. When the hot water issues from the fountain, it frcquently spreads over a superficies of some extent; so far as it reaches, on either hand, there is a deposition of, or growth of green matter. Several lamina of this green matter will be found lying over each other, and immediately under, and in contact with the inferiour lamina, which is not thicker than paper, is found a whit'sh substance resembling a coagulum ; when viewed with a microscope, this last is also found to consist of several, sometimes a good number of famina, of which that next the green is the finest and thinnest, being the last formed ; those below increasing in thickness and tenacity, until the last terminates in a soft earthy matter, which reposes in the more solid rock. Each lamina of the coagulum is penetrated in all its parts by calcareous grains, extremely minute, and divided in the more recent web, but much larger and occupying the whole of the inferiour lamina. The understratum is continually consolidating, and adding bulk and height to the rock. When this acquires such an elevation as to stop the passage of the water, it finds another course over the rock, hill, or margin of the creek, forming in turn, accumulations of matter over the whole of the adjacent space. When the water has found itself a new channel, the green matter, which sometimes acquires a thickness of half an inch, is speedily converted into a rich vegetable earth, and becomes the food of plants. The surface of the calcareous rock also decomposes and forms the richest block mould intimately mixed with a considerable portion of soil ; plants and trees vegetate luxuriantly upon it. On examining a piece of ground, upon which the snow dissolved as it fell, and which was covered with herbage, they found, in some places, a calcareots crust on the surface; but in goneral a depth of from five inches to a foot of the richest black monid. The surface was sensibly warm to the touch. In the air the mercury in the thermometer stood at 44° ; when placed four inches under the surface, and covered with earth, it rose rapidly to 69° 5

and upon the calcareous rock, eight inches beneath the surface, it rose to 80°. This result was uniform over the whole surface, which was about a *]uarter of an acre. On searching they found a spring, about fifteen inches under the surface, in the water of which the thermometer she wed a temperature of 130°. Beneath the black mould was found a brown mixture of lime and silex, very loose and divisible, apparently in a state of decomposition, and progressing towards the formation of black mould : under this brownish mass it became gradually whiter and harder, to the depth of from o to twelve inches, where it was a calcareous sparkling stone. It was evident that the water had passed over this place, and formed a flat superficies of silicious lime stone ; and that its position, nearly level, had faciliated the accumulation of earth, in proportion as the decomposition advanced. Similar spots of ground were found higher up the hill, resembling little savannas, near which hot springs were always discovered, which had once flowed over them. It appears probable that the hot water of the springs, at an early period, had all issued from its grand reservoir in the hill, at a much greater elevation than at present. The calcareous crust may be traced up, in most situations on the west side of the hill looking down the creek and valley, to a certain: height, perhaps one hundred feet perpendicular ; in this region the hill rises precipitously, and is studded with hard silicious stones ; below the descent is more gradual, and the soil a calcareous black earth. It is easy to discriminate the primitive hill,from that which has accumulated, by precipitation, from the water of the springs ; this last is entirely confined to the west side of the hill, and washed at its base by the waters of the creek, no hot spring being visible in any other part of its circumference. By actual measurement along the base of the hill the influenee of the springs is found to extend seventy perches, in a direction a little to the east of north ; along the whole of this space the springs have deposited stony matter, calcareous, with an addition of silex, or crystalized lime. The accumulation of calcareous matter is more considerable at the north end of the hill than the south ; the first may be above a hundred feet perpendicular, but sloping much more

gradually that the primitive hill above, until it approaches the creek, where

not unfrequently it terminates in a precipice of from six to twenty feet. The difference between the primitive and secondary hill is so striking, that a superficial observer must notice it ; the first is regularly very steep, and studded with rock and stone of the hardest flint and other silicious compounds, and a superficies of two or three inches of good mould covers a red clay below, on the secondary hill, which carries evident marks of recent formation, no flint, or silicious stone, is found ; the calcareous rock conceals all from view, and is, itself, frequently covered by much fine rich earth. It would seem that this compound, precipitated from the hot waters, yields easily to the influence of the atmosphere ; for where the waters cease to flow over any portion of the rock, it speedily decomposes ; probably more rapidly from the heat communicated from the interiour of the hill,as insulated masses of the rock are observed to remain without change. The cedar, the wax myrtle, and the cassima yapon, all evergreens, attach themselves particularly to the calcareous region, and seem to grow and thrive even in the clefts of the solid rock. A spring, enjoying a freedom of position, proceeds with great regularity in depositing the matter it holds in solution ; the border or rim of its basin forms an elevated ridge, from whence proceeds a glacis all around, where the waters have flowed for some time over one part of the brim ; this becomes more elevated, and the water has to seek a passage where there is less resistance ; thus forming, in miniature, a crater, resembling in shape *ue comical summit of a volcano. The hill being steep above the progress

of petrifaction is stopped on that side, and the waters continue to flow and spread abroad, incrusung the whole face of the hill below. The last formed calcareous border of the circular basin is soft, and easily divided ; at a small depth it is more compact ; and at a depth of six inches it is generally hard white stone. If the bottom of the basin is stirred up, a quantity of the red calx of iron rises, and escapes over the summit of the crater. Visitants to the hot springs, having observed shrubs and trees with their roots in the hot water, have been induced to try experiments, by sticking branches of trees in the run of hot water. Some branches of the wax myrtle were found thrust into the bottom of a spring run, the water of which was 130°. by Fahrenheit's thermometer ; the foliage and fruit of the branch were not only sound and heal, hy, but at the surface of the water roots were actually sprouting from it : on pulling it up the part which had penetrated the hot mud was found decayed, w The green substance discoverable at the bottom of the hot springs, and which at first sight has the appearance of plush, on examination by the microscope, was found to be a vegetable production. A film of green matter spreads itself on the calcareous base, from which rise fibres more than half an inch in length, forming a beautiful vegetation. Before the microscope it sparkled with innumerable modules of lime, some part of which was beautifully crystalized. This circumstance might cause a doubt of its being a true vegetable, but its great resemblance to some of the mosses, particularly the byssi, and the discovery which Mr. Dunbar made of its being the residence of animal life, confirmed his belief in its being a true moss. After a diligent search he discovered a very minute shell fish, of the bivalve kind, inhabiting this moss ; its shape nearly that of the fresh water muscle ; the colour of the shell a greyish brown, with spots of a purplish colour. When the animal is undisturbed it opens the shell, and thrusts out four legs, very transparent, and articulated like those of a quadruped ; the extremities of the fore legs are very slender and sharp, but those of the hind legs somewhat broadcr; apparently firmed with minute toes : from the extremity of each shell issues three of four forked hairs, which the animal seems to possess the power of moving ; the fore legs are probably formed for making incisions into the moss for the purpose of procuring access to the juices of the living plant, upon which, no doubt, it feeds : it may be provided with a proboscis, although it did not appear while the animal was under examination : the hind legs are well adapted for propelling it in its progress over the moss, or through the water. It would be desirable to ascertain the cause of that perpetual fire, which keeps up the high temperature of so many springs, as flow from this hill, at a considerable distance from each other ; upon looking around, however, sufficient data for the solution of the difficulty is not discoverable. Nothing of a volcanick nature is to be seen in this country : neither could they learn that any evidence in favour of such a supposition was to be found in the mountains counected with this river. An immense bed of dark blue schistus appears to form the base of the hot spring hill, and of all those in its neighbourhood : the bottom of the creek is formed of it; and pieces are frequently met with rendered soft by decomposition, and possessing a strong alumnious taste, requiring nothing but lixiviation and crystalization to compiete the manufacture of alum. As bodies undergoing chemical changes generally produced an alteration of temperature, the heat of these springs may be owing to the disengagement of calorick, or the decomposition of the schistus : another and perhaps a more satisfactory cause may be assigned : it is well known, that within the circle of the waters of this river vast beds of martial pyrites exist; they have not yet, however, been discovered in the vicinage of the hot springs, but may, nevertheless, form immense beds under the bases of these hills ; and as in one place at least, there is evidence of the presence of bitumen,” the union of these agents will in the progress of decomposition, by the admission of air and moisture, produce degrees of heat capable of supporting the phenomena of the hot springs. No sulphurick acid is present in this water ; the springs may be supplied by the vapour of heated water, ascending from caverns where the heat is generated, or the heat may be immediately applied to the bottom of an immense natural caldron of rock, contained in the bowels of the hill, from which as a reservoir the springs may be supplied. A series of accurate observations determined the latitude of the hot springs to be 34° 31' 4", 16 N. and long Gh. 11' 25", or 92° 50'45" west from the meridian of Greenwich. While Mr. Dunbar was making arrangements for transporting the baggage back to the river camp, doctor Hunter, with a small party, went on an excursion into the country. He left the hot springs on the morning of the 27th, and after travelling sometimes over hills and steep craggy mountains with narrow valleys between them, then up the valleys and generally by the side of a branch emptying into the Washita, they reached the main branch of the Calfat in the evening, about twelve miles from the springs. The stones they met with during the first part of the day were silicious, of a whitish-grey, with flints white, cream-coloured, red, &c. The beds of the rivulets, and often a considerable way up the hills, shewed immense bodies of schistus, both blue and grey, some of it efflorescing and tasting strongly of alum. The latter part of the day, they travelled over and between hills of black, hard, and compact flint in shapeless masses, with schist as before. On ascending these high grounds you distinctly perceive the commencement of the piney region, beginning at the height of sixty or seventy feet and extending to the top. The soil in these narrow valleys is thin and full of stones. The next day, which was stormy, they reached a branch of the bayau de saline, which stretches towards the Arkansa, and empties into the Washita many leagues below, having gone about twelve miles. The mountains they had passed being of the primitive kind, which seldom produce metals, and having hitherto seen nothing of a mineral kind, a little poor iron ore excepted, and the face of the country, as far as they could see, presenting the same aspect; they returned to the camp, at the hot springs, on the evening of the thirtieth, by another route, in which they met with nothing worthy notice. In consequence of the rains which had fallen, Mr. Dunbar, and those who were transporting the baggage to the river camp, found the road watry. The soil on the flat lands under the stratum of vegetable mould is yellowish, and consists of decomposed schistus, of which there are immense beds in every stage of dissolution, from the hard stone recently uncovered and partially decomposed to the yellow and apparently homogeneous earth. The covering of vegetable earth between the hills and the river is, in most places, sufficiently thick to constitute a good soil, being from four to six inches; and it is the opinion of the people npon the Washita, that wheat will grow here to great perfection. Although the higher hills, three hundred to six hundred feet in height, are very rocky, yet the inferiour hills, and the sloping bases of the first, are generally covered with a soil of a middling quality. The natural productions are sufficiently luxuriant, consisting chiefly of black and red oak, intermixed with a variety of other woods, and a considerable undergrowth. Even on these rocky hills are three or

* Having thrust a stick down into the crater of one of the springs, at some distance up the tol, several or os of petroleum, or naptha, rose and spread upon the surface : it cea-cd to rise after three or four attempts.

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