defended the accuracy of the account of Mrs. Graham, called on the Reviewer, to inquire whether Dr. Meyen had any observations besides the extracts given by him, and to compare the translation with the original. One point appearing to be expressed in rather a loose manner, it was resolved to write to Dr. Meyen, who returned a very polite answer, which now lies before us, and in which he says, "I was acquainted with Mr. Greenough's dispute with Mrs. Graham from its commencement, and received last year (1834) all the papers on the subject from Baron A. von Humboldt, to whom they had been sent by Mrs. Graham. You mention a passage in my work (p. 213) which you think seems to be expressed in a vague manner, as if I doubted the reality of the elevation. I cannot see it in this light, but you perhaps allude to the passage where I speak of the elevation of a tract of country 400,000 miles in extent, as affirmed by a late traveller. This statement certainly appears very strange, as there are no facts whatever to show that the interior of the continent has been elevated, and it is therefore impossible to estimate the superficial extent of the country so raised; it is only on the coast that the elevation can be observed. In a short paper in Berghaus' Journal for November 1834, to which I refer you, I touch on the essential points which you and Mr. L-1 allude to, but I will add some particulars. The remains of animals and tang, which adhere to the rocks elevated in 1822, were certainly still to be seen in 1881, and this is easily accounted for by the very firm ligneous stem of the Laminariæ, (Lessonia of Bory de St. Vincent,) especially as the sea often rises so high as again to cover the rocks that have been elevated."

In the paper alluded to Dr. Meyen says that, the province of Tarapaca has received from nature a peculiar present, namely, minas de Leña, (i. e. wood-mines,) which the inhabitants use as fuel in their saltpetre works, though probably there is not a single tree in all the surrounding country. This substance is not coal, but is stated to be dry timber, easily cleft, immense forests of which are buried under the sand of that plain. The trees all lie prostrate, with their heads towards the coast, and are reported to be now covered with sand. This phenomenon, he adds, is one of the most remarkable of the west coast of America, and till the subject shall be accurately investigated it affords occasion for manifold conjectures. If those forests belong to the existing creation, the whole country must have been so changed by dreadful elevations of the Cordillera, that, instead of the damp plains of a tropical climate, there are now the most dreary sandy wastes. The buried timber is said to be dry, as easy to split as our timber, and to burn with an equally bright flame.

"What can be a stronger confirmation of the gradual elevation of the Cordillera in South America, than the terrace-like conformation of this chain, which I found to be quite decided at most of the points of Chili and Peru which I visited? And does not the overthrow of these forests prove, likewise, such an elevation of this country in recent times? I mention these remarkable facts, because many unfounded doubts have of late been expressed in England concerning the elevation of whole tracts of country in consequence of earthquakes or volcanic action in general, though they may be clearly observed on the coast of Chili."

Notwithstanding the observations of Dr. Meyen, confirming the elevation of the coast, doubts were still entertained of the fact, and at a meeting of the Geological Society in December last, two letters were read on the question whether the earthquake of 1822 had produced any change in the relative level of land and sea on the coast of Chili? One of these letters was from Lieutenant Bowers, R.N., the other from Mr. Cuming, an eminent conchologist, both of whom were at Valparaiso before and after the earthquake of 1822, (the latter, for several years afterwards, a resident,) who declared that they had not noticed any such change. Great importance was attached to Mr. Cuming's statement in particular, because he had collected shells on the rocks upon the coast, and it might be taken for granted, that if any. change had occurred he must have perceived it.

Though Mr. Lyell, in the fourth edition of his Principles of Geology, speaks of the elevation of the coast of Chili as an undoubted fact,-" we know," says he, " that an earthquake may raise the coast of Chili for 100 miles to the average height of about five feet," yet the difficulties with which the subject is still surrounded, caused him, after quoting the several statements of Mrs. Graham, Dr. Meyen, and Mr. Cuming, to express a wish that the scientific traveller and resident in Chili may institute more minute inquiries. We have, for this reason, thought fit to translate entire the following passage from Dr. Poeppig, confirming the fact of the elevation of the coast; all doubts of which are, we conceive, removed by the account of the dreadful earthquake which desolated Chili in February, 1835, transmitted by our friend and correspondent, Alexander Caldcleugh, Esq., resident in Chili, which was read before the Royal Society, Feb. 14, 1836, in which he states that the island of Santa Maria, south of the Bay of Conception, was permanently elevated ten feet. A similar change was found to have taken place in the bottom of the sea, immediately surrounding the island. The amount of this elevation was very accurately ascertained by the observations of Captain Fitzroy, who had made a perfect survey of the shores of

that island previously to the earthquake, thereby affording the most satisfactory and authentic testimony to this important fact.

"I have frequently waded, not without some danger, through the river to Concon, as there was a very interesting tract on the opposite bank. This attempt required some little caution, because the ford which traverses the deep and rapid river in a zigzag direction, changes its line after every inundation. Extensive sand-hills, resembling the downs of Holland and England, stretch along the sea-coast to the north of the river. They are composed of a fine white sand, in which we easily discover the original component particles of sienite, which is the predominant rock on this coast, and which foliates at its surface with a facility not usual in our parts of the world, and becomes a friable and very light kind of stone. Not having any certain direction (though it seems to be parallel with the more solid rocks further inward), these accumulations of light and shifting sand would be continually changing their place, were they not formed around solid nuclei, where they range themselves first on one side and then on the other, according as they are driven by the wind. Enormous beds of conchylia and shells are scattered along the north coast, imbedded in a ferruginous clay, or indurated sand; sometimes united like breccia, sometimes in nests, or in longer chains. But they not merely extend along the surface, or higher up the hilly banks, as we might infer from the communications of many careless observers, which may, perhaps, even have been copied from others; but in reality reach to an unknown depth, and their termination has not been discovered, even at twenty feet below the level of the sea: on the other hand, we find them at an elevation of forty feet above its surface, in perfectly compact strata, which are enclosed by the drift sand-hills. It is very remarkable, that these accumulations of marine animals consist entirely of species which are, indeed, found alive to this day in the same locality, but are by no means the exclusive inhabitants of the deep. Among such we must particularly mention the Loco (Murex. Mol.), which is easily recognized, and which the fishermen still take on this coast, but must formerly have existed here in almost incredible numbers, as the beds of shells, which to the north of Concon alone extend, in a distinctly marked ridge of hills, above three geographical miles in length, are in some parts wholly composed of this animal. We seldom find them mixed with other kinds, and least of all with bivalve shells, but which may always be traced to living and well-known species. It is difficult to say what causes can have produced such extraordinary accumulations of animals of the same species within a very small space; for they are altogether different from other conglomerations of shells, which, as in Southern Chili, for example, are often found at a great distance from the sea, and generally at a considerable elevation above it, and in which we discover genera and species of an antediluvian world, of the utmost variety; and in the interior of Peru, on the other side of the Andes, where entire hills of shells and other marine animals have been discovered (La Ventanilla) between the slate mountains of Cassapi in

the province of Huanuco, in which there is not the slightest trace of any of the very few kinds of crustacea that at present inhabit the seas along the Peruvian coast. The lost species of the singular tribe of the Pentacrinites, and beautifully formed coral plants, which bear some resemblance to those of the South Sea islands, can be plainly distinguished, although they are so closely imbedded in the more recent rock, that it is only by a very lucky fracture that any perfect specimen can be obtained. In a country which, like the north of Chili, has scarcely any other kinds of rock but the volcanic and granite, lime is an article of importance, and hence the possession of these otherwise unprofitable downs affords considerable gain. They belong to the proprietor of the hacienda of Quintero, who regularly digs for these shells, and thus supplies the greatest part of the lime used at Valparaiso. The poor peasant in the neighbourhood of Quintero avails himself of the same gift of nature, but it is only upon payment of a small sum that he can obtain permission to dig in one of these hills, and to load his mule with its never-failing produce.

"The sea-coast in this district, as well as further southward, probably consisted originally of perpendicular walls of rock, which, though more remote from the ocean, still mark the ancient boundaries. Between their foot and the sea run these hills of driftsand, upon which a more solid and promising soil has been very slowly formed, but only in a few spots. There can be no doubt that the origin of these hills is of comparatively modern date, and may be attributed to two causes: one, as being the most striking, has been repeatedly mentioned, though it would seem that too much stress has been laid on it as a foundation for general conclusions. It consists in the rapid and unconnected rising and elevation of whole districts along the coast, which has been observed to take place in all the greater earthquakes in Chili, and was particularly striking during the great earthquakes of 1822. I have, myself, frequently searched at low tide for marine animals, especially for the beautiful Chitoneæ, on a chain of cliffs, in the middle of the little bay of Concon, where only six years ago the fishermen were unable to obtain a footing even at very low water-proof sufficient that an elevation of at least six feet in a perpendicular direction must have taken place here. But the formation of the broad and very uniformly flat coast district, on which only sea-sand lies, cannot be attributed in the same exclusive manner to this undeniable phenomenon. The less striking fact, of the gradual recession of the sea from the coast of Chili, has hitherto been very much overlooked, though it is well known to 'many of the older inhabitants of the coast. We shall see, in the sequel, that, in the southern parts of the republic, even entire plains (la Vega de Concepcion) have arisen through the retreat of the sea, since the first arrival of the Europeans, which are, therefore, facts that may be ascertained with historical certainty. On the rocks which run parallel with the ocean to the north of Concon, but are separated from it by sand hills and a broad barren beach, we easily perceive the traces of the beating of the waves in stratifications very near to each other, which is a proof of a very gradual subsiding of the waters but not of

an elevation of the ground by fits, of which this latter appears scarcely susceptible, because it consists, to a great depth, of loose sand. The formation of firm land is particularly striking in all those places where ranges of cliffs rise at some distance from the coast, and it is evident that many a cape was formerly an island, which has been united with the continent by low tracts of land, produced by alluvion and the retiring of the sea. The accumulation of sand in the mouths of the larger rivers--for instance, of the Biobio-and the constantly increasing difficulty of access to many harbours, for instance, of the Maule and of the smaller entrance (boca chica) of the port of Talcahuano, likewise indicate what we have just mentioned. But I do not mean to deny, on that account, that an extraordinary collection of volcanic power slumbers in the depths of the great ocean, which manifests itself occasionally, but then in a truly terrific manner, and may have the effect, even in our days, of raising large islands. Volcanic islands of a very recent date were observed in the South Sea by Captain Beechy, and others were discovered and examined, almost at the very moment of their origin.

"The information which was given me of the numerous animals to be met with in the environs of the hacienda of Quintero, induced me to make many excursions after my arrival in Concon, which always procured me something new, and amply rewarded the fatigue which generally attended them. The white downs reflect the light so strongly that you soon feel your eyes very painfully affected; and the sand is so heated by the sun, that even the countryman, who is inured to the inconvenience, is obliged to protect the soles of his feet by pieces of leather. Thermometers, the correctness of which had been proved, were often put into the sand, thirteen inches below the surface, in the afternoon, and though the experiments were made with the greatest care, they indicated the heat of the sun as varying from 40° to 58° (of the Centigrade thermometer), accordingly as the morning had been bright or cloudy, or a slight rain had fallen in the night, &c.; and this hot soil of the Chilian downs, which in summer is twice as warm as the atmosphere, nourishes in the more shallow spots a great number of interesting plants, among which the botanist is much surprised by the sight of a Mesembryanthemum, a singularly formed representative of the Flora of Africa, and the only species of that very numerous genus that occurs in the New World. * * * The beach, composed of very fine sand, being moistened by the sea and become hard, is equal to the best gravel walks in a garden. But the incautious wanderer is exposed to great embarrassment, if not acquainted with the state of the moon he sets out just when the sea again begins to swell, and every fresh wave rolls some fathoms further over the flat coast, when even with the utmost speed no hope of escape remains. Though there is not the same danger of inevitable destruction as on the treacherous sand-banks of the Scottish coast, yet the only alternative here is to ascend the downs, and to pursue his painful journey, while at every step he sinks knee-deep into the burning sand. Such expeditions, however, often unexpectedly lead us upon rare animals, which amply compensate for all our troubles.

VOL. XVII. NO. XXXIII.

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