THE

AMERICAN

JOURNAL OF SCIENCE AND ARTS.

[SECOND SERIES.]

ART. I.-Account of some Volcanic Springs in the Desert of the Colorado, in Southern California; by JOHN L. LECONTE, M.D.

IN October, 1850, being at Vallecitas, San Diego Co., California, it was my good fortune to make a visit, in company with Major Heintzelman and Mr. Matsell, to certain boiling springs, not similar to any which have been noticed in our territory; and as the only account yet given of them has appeared in a newspaper, it seemed to me, that the rough notes taken while making the visit, might with slight changes be of interest to my scientific friends.

Mysterious accounts had been given us of a 'Volcan' situated in the midst of a plain covered with salt, near the shore of a lake: and although most of the salt used by the inhabitants of the mountains east of Santa Isabel was brought from this lake, no very definite account either of the distance of the lake, or of the phenomena to be seen there, could be procured. It was only apparent that some awe-inspiring object had heretofore defended itself against the prying curiosity of man.

Major Heintzelman, then in command of the troops about to be stationed at the Gila river, having determined to visit these objects of unknown interest, kindly offered me an opportunity of joining his party.

Having secured as guides the interpreter from Santa Isabel, and the head chief of the 'Lleguina' Indians living near the Salt Lake, we left San Felipe a short time after the rising of the moon on the morning of the 28th of October.

SECOND SERIES, Vol. XIX, No. 55. Jan., 1855.

1

Entering almost immediately a small cañon, by which we ascended a rocky ridge, we soon descended again into a narrow deep cañon trending N.E.; this we followed for several miles, encountering in our route many precipitous places, over which we had great difficulty in leading our horses. The rocks were metamorphic, of a gueissoid and sienitic character, and the scanty vegetation was similar to that of Vallecitas; the most conspicuons objects being Larrea mexicana, Fouquiera spinosa, Prosopis, Agave and a variety of brittle and uncouth looking Opuntiæ, both of the flattened and cylindrical forms.

The cañon finally entered a long valley, in which were remains of some Indian huts, now abandoned from the failure of water. The valley opened abruptly by a gap through the most eastern mountain range, and at 8 A. M. we found ourselves on the edge of the great desert, though still considerably above the general level of its surface. An extensive but peculiarly uninteresting prospect was before us; an immense plain extended to the eastern horizon, broken towards the north by some slight inequalities; masses of rock lay around us on the mountain side; the mountain itself, appeared a wall of naked rocks, and it was only within a small circle of vision, that an earth colored vegetation could be observed; as if the influence of our own living selves had communicated a fictitious vitality to the spot where we stood, which soon would depart with us, and leave the ghosts of plants to shrink again into the rocks from which they had been evoked by our presence.

At an indefinite distance towards the N. E. was seen a low range of mountains, near which a silvery surface with a slight fog resting over it seemed to indicate water. This the guides declared was the Salt Lake, on the shores of which were the objects of our search, and confidently assured us that we should reach it before night.

Halting here for breakfast, some excellent capon, and hard bread, washed down with a limited draught from our canteens soon prepared us for the dreary ride; the only resources to shorten the way being very limited geology, and as may be inferred from the nature of the country, equally poor botany. It is no wonder that Government reports abound with names of plants, which suggest nothing but linguistic difficulties, for there is little else in the vast deserts of Western America to occupy the attention of the intelligent traveller; and with the determination of one resolved to struggle with the dull sublimity of inorganic matter, he frequently breaks off and preserves a piece of some hideous vegetable, whose only charms are the ugliness of its form, the lifelessness of its color, and the apparent absence of flower, and foliage, and every thing else that renders a plant attractive.

Overlying the metamorphic rock was seen a conglomerate of great thickness, similar to that which at Vallecitas forms the

greater portion of the eastern range of the Sierra: boulders frequently of immense size, but scarcely rounded, torn in former ages from the adjacent ranges of mountains, are cemented together by a small quantity of calcareous matter enveloping gravel of different degrees of fineness: this cement presents somewhat the appearance of bad mortar. Outside of this conglomerate was seen unstratified drift. Beyond the mountains, can be traced on the desert a tertiary formation similar to that of San Diego, and above this stratified drift. These formations are nearly horizontal and form low ridges. The vegetation was still similar to that of Vallecitas, with the addition of a very large Echinocactus, of which several grew occasionally from one base: Opuntia vaginata was also seen, and an Ephedra appeared with a species of Koeberlinia. These gradually faded out, till at last nothing remained but Prosopis, Larrea, and a plant at that season leafless. The desert contains three principle levels; of these the upper (consisting of the part near mountain ridges) is covered with gravel, small stones from the mountains, silicified wood and oyster shells; the middle level is sandy, and the lower one clayey, with great numbers of fresh water shells scattered over its surface: among these the only bivalve is a species of Anodon, now found in the Colorado River, (A. californiensis Lea); the other species are small univalves, belonging to Physa, and Amnicola. These clayey parts extend for many miles, and are evidently the beds of lagoons, which on rare occasions may be filled with water; they belong to the New River system of overflow, hereafter to be described. Having travelled from the mountains a nearly east course, we encamped about 4 P. M. on the bank of a small stream running northwardly to the Salt Lake: the banks were precipitous, about twenty feet in height, and the waters disagreeably saline. This stream is evidently Cariso creek, which being lost in the sands a few miles from its source here reappears on the lower level of the desert: some rushes growing on the edge of the water furnished food for our horses.

Starting the next morning at 3 A. M. we arrived about 10, at an Indian village situated on New River, which is here near its termination, and probably when the supply is abundant, sends a portion of its water to the Salt Lake: at present there are only two or three small pools near the village.

New River is an important object to those compelled to cross the desert, since from it is derived the chief supply of water, to be found between Cariso creek and the Colorado. It is in reality a slough of the latter, which is only different from the ordinary sloughs near the river by its greater length, extending by a very tortuous course 70 or 80 miles from the point where it leaves the river. The bed of the Colorado, like that of other rivers carrying a large amount of sediment, is above the lower portions of the adjacent country, which are thus, in time of overflow supplied

by these sloughs; frequently however the annual rise of the river is not sufficient to supply New River with water, and should this occur for two years in succession the lagoons along its course become entirely dry, and the difficulty of crossing the desert is much increased.

The whole course of New River is marked by a large species. of Chenopodium, called 'Kelite' by the natives, and 'careless weed' by the emigrants; it furnishes almost the only food for cattle and horses to be found in this region: the seeds are used by the Indians in preparing a kind of cake, which is quite palatable, when nothing else can be procured. The green leaves (if they ever are green) may be used as a salad, or boiled as a vegetable.

The ground passed over before arriving at the village was in many places covered with a thin layer of sandstone, forming occasionally concretions like claystones; this sandstone has apparently been formed by springs similar to those seen afterwards. The dust was sometimes extremely fine and incoherent, so that the feet of the horses would sink from six to eight inches; many pieces of pumice were also found stranded on the surface.

The Indian village contained about fifty inhabitants, who received us in a very friendly manner, offering us melons, beans and pumpkins, which they raise in abundance. Visiting the village were some Yumas from the Colorado, who recounted to Major Heintzelman the depredations committed by the grand army of California, recently sent under one Major General Morehead, to avenge the murder of a party of ferrymen at the junction of the Colorado and Gila. Though these depredations were not remarkable, the Indians had apparently had enough of the war, and learning that a military post was soon to be established, they became very anxious to make peace, until another opportunity for safely committing some outrage should occur.

After resting our horses, we started with an escort of seven or eight Indians, who used all the power of their eloquence to dissuade us from going. Nevertheless, on our exclaiming that we had come a long distance to see these volcanoes, and that we would seek them for ourselves, if they were afraid to accompany us, the debate ceased, and we rode on in a northwesterly direction. After going about eight miles, we reached a soft muddy plain bordering the Salt Lake: the salt in consequence of a recent shower had almost disappeared, only a few crusts about half an inch thick now remaining. The deposit is said to be sometimes a foot in thickness.

North of the lake, and now distant from us six or eight miles, is a chain of rocky hills 800-1000 feet high, portions of which have a volcanic appearance. Rising from the plain, where we now stand, are several volcanic mounds about 100-150 feet high; hastening to one of these, I found it composed of lava,

and pumice: several of these mounds are arranged in an arc of a circle, but the general direction is a little west of south.

Having arrived thus far, and given our horses in charge to some of the Indians, the interpreter again endeavored to dissuade us from further exploration. He said that on approaching the springs, the steam from which was now distinctly seen, devils in the shape of large black birds rose from the ground, and descended with overwhelming force on the head of the rash adventurer: he stated that a tradition still existed among the Indians, of one Juan Lonquiss (Longecuisse? perhaps a "Crapaud" trader) who had met this dreadful fate, and asked us in a pathetic tone, how he could return to his town, if we too were sacrificed in this way. We replied, in substance, that devils had no power over us, and that we were stronger than they, and that probably they were aware of that fact, and would not appear during our visit.

This seemed very blasphemous to their ears, and the whole escort suddenly dropped behind, leaving us to our fate.

Advancing towards the place, whence the steam issued, we found in the muddy plain numerous circular holes containing boiling mud, and exhaling a naphtha-like odor. Many of them are encrusted with inspissated mud, forming cones 3-4 feet high, from the apex of which proceed mingled vapors of water, sal-ammoniac and sulphur. Four of them eject steam and clear saline water, with great violence, resembling in appearance the jet from the pipe of a high-pressure engine. The falling spray around these has formed a group of acicular stalagmites, composed of aragonite with a small quantity of silica and some saline matter: many of these stalagmites are tubular in form. Another spring was a large basin filled intermittingly to overflowing with foam and clear saline water around the edge were botryoidal masses of aragonite, like that forming needles around the cones. Near the cones, in little fissures, were crusts of sal-ammoniac,* some of which were colored red, possibly by sulphuret of selenium.

The Indians, finding that the black devils did not assail us, ran up to us, with great exultation, and leaped about, and danced in such an extravagant manner, that we were obliged to caution them of the danger of breaking through; the solid crust was evidently very thin, as it bent and trembled under our weight in a very threatening manner.

In returning we found on the most northern of the volcanic mounds before mentioned a quantity of scoria and obsidian, and distinctly traced the course of a lava stream down the side. The mounds all showed traces of aqueous action, in the terracelike manner in which the pumice was arranged. The rest of our

* The specimens of saline crusts having been subsequently lost, I cannot be certain that they were really sal-ammoniac, and only refer them to that salt from the sharpness of their taste."