nic antiquity. The spring of Erosinos, two leagues in this state of repose mud-volcanoes often continue south of Argos, in the declivity of Chaon, is even for centuries. The production of mud-vocanoes is mentioned by Herodotus. At Delphi, the Cassotis accompanied by earthquakes, subterranean thun(the so-called Wells of St. Nicholas) still rises to der, the elevation of a whole district of country, the south of the Lesche, and flows under the and the eruption of flames, which rise high, but Temple of Apollo; the Castalia, too, at the foot last only for a short time. When the mud-volcano of Phædriada, and the Pirene at Acrocorinth, are of lokmali made its appearance in the peninsula of there, as well as the hot baths of Edepsos in Abscheron, eastward from Baku, on the Caspian Cubea, in which Sulla bathed at the time of the Sea, (on the 27th of November, 1827,) flames burst Mithridatic war. I gladly adduce these particu- forth, and blazed up to an extraordinary height for lars, because they forcibly remind us how, in a a period of three hours; for the next succeeding country exposed to earthquakes so frequent and so twenty hours they scarcely rose three feet above violent, the interior of our planet has been able to the surface of the crater that discharged the mud. preserve its spring canals unaltered for 2000 years The column of flame mounted to such a height at least. The Fontaine Jaillissante of Lillers, in near the village of Baklichi, westward from Baku, the department of the Pas de Calais, was bored in that it was seen at the distance of six (German) the year 1126, and ever since then has the water miles. Great blocks of stone, torn from their founflowed uninterruptedly to the same height, and in dations beneath, were scattered widely around. the same quantity. The excellent geographer of Similar blocks are observed about the now slumthe Caramanian coasts, Captain Reaufort, more-bering mud-volcanoes of Monte Zibio, near Sassuover, observed the same flame, fed by a stream of olo, in the north of Italy. The second state, or inflammable gas, which flows out in the district of that of activity, has continued for 1500 years in the Phaselis, which Pliny describes as the flame of mud volcano of Girgenti, (Macalubi,) in Sicily, Chimera in Lycia. which is described by the ancients. Many conical The observations made by Arago in 1821, that hillocks, of eight, ten, and even thirty feet high, the deeper Artesian wells are the warmer, was the though the height, as well as the form, of these first means of throwing a great light upon the varies at different times, are there seen arranged origin of thermal springs, and led to the discovery near one another. From the superior very small of the law of the increase of the temperature of basin, which is full of water, along with the perithe earth according to the depth. It is remarkable, odic escapes of gas, there are periodic streams of and only noticed in very recent times, that St. clayey mud discharged. The mud of these volPatricius, probably Bishop of Pertusa, was led to a canoes is generally cold, but occasionally, as at very correct view of the phenomenon which pre- Damak, in the province of Samarang, island of sented itself in the appearance of hot springs near Java, it is of high temperature. The gases, Carthage, at the end of the third century. When which escape with a rushing noise, are also of questioned as to the cause of the boiling-hot water different kinds-hydrogen gas, mixed with naphwhich poured out from the earth, he answered :- tha; carbonic acid; and, as Parrot and I ascer"Fire is nourished in the clouds, and in the in-tained, (in the peninsula of Taman and the South terior of the earth, as Etna, and another mountain American Volcancitos de Turbaco,) almost pure in the neighborhood of Naples, inform you. The nitrogen gas. subterranean waters rise as through syphons; and the cause of the heat of hot springs is this: the waters that are more remote from the subterraneous fire show themselves colder; those that flow in closer proximity to the fire, warmed by it, bring an insupportable heat to the surface which we inhabit."

As earthquakes are frequently accompanied by eruptions of water and watery vapor, so do we perceive in the salses, or the small mud-volcanoes, a transition from the alternating phenomena presented by jets of vapor and thermal springs to the great and frightful activity of hills that vomit forth lava. If these, as springs of melted mineral matter, produce volcanic rocks, so do the thermal springs that are charged with carbonic acid and sulphurous gas, (and earthy matters,) produce, by incessant precipitation, either horizontal beds of limestone, (travertin,) or they form conical hillocks, as in the north of Africa, (Algeira,) and the Banos of Caxamarca, on the western declivity of the Peruvian Andes. In the travertin of Van Dieman's Land, not far from Hobart Town, there are contained, according to Mr. Charles Darwin, the remains of an extinct flora. By lava and travertin, two species of rock, the production of which goes on under our eyes, we here indicate the grand antithesis in geognostical relations.

Mud-volcanoes (salsen) deserve a greater share of attention than geologists have hitherto bestowed upon them. The extent of the phenomena has been overlooked, because in the two states in which it presents itself to us, the one of repose is that which has been principally dwelt upon; and

Mud-volcanoes, after the first forcible outburst of flame, which perhaps is not common to all in the same measure, present the observer with a picture of an activity of the interior of the earth, that proceeds incessantly but feebly. The communication with the deep strata, in which a high temperature prevails, is speedily interrupted again; and the cold discharges of mud-volcanoes seem to indicate that the seat of the phenomenon, in its state of continuance, cannot be very remote from the surface. The reaction of the interior of the earth upon its outer crust is exhibited in a very different degree of force in the proper volcanoes, or burning mountains; in other words, in those points of the earth where a permanent communication, or, at all events, a communication that is renewed from time to time, is established between the surface and the deep focus of ignition. We must carefully distinguish between more or less exaggerated volcanic phenomena, such as earthquakes, hot springs and jets of steam, mud-volcanoes, the rising up of bell and dome-shaped unopened trachytic mountains, the opening of these mountains, or the upheaval of basaltic beds as craters of elevation, lastly, the rise of a permanent volcano within the crater of elevation itself, or amongst the fragments of its previous constitution. At different times, along with different degrees of activity and force, permanent volcanoes throw out jets of aqueous vapor, acids, glowing ashes and scoriæ, and, when the resistance can be overcome, ribbon-shaped small fiery streams of melted earthy matter.

As a consequence of a great but local manifes

Their origin is not connected with any particular mountain rock; they break out in basalt, trachyte, leucitic porphyry, (Somma,) or in doleritic aggregates of augite and Labrador. Hence the very dissimilar natures and external forms of this kind of crater edge. "No eruptive phenomena take place from such boundaries. Through them there is no permanent channel of communication established with the interior; and it is only very rarely that traces of still active volcanic power are discovered in the precincts, or within the circuit of such craters. The force competent to bring about such important effects, must long have accumulated, and gained strength in the interior, before it could have overcome the resistance of the superincumbent masses. On the formation of new islands, it raises up granular rocky masses and conglomerates (layers of tufa full of marine plants) above the level of the sea. Compressed gases escape through the crater of elevation; but a mass of such magnitude, thus upheaved, sinks down again, and closes forthwith the openings, which are only formed for such manifestations of force. No volcano is produced."

tation of force in the interior of our planet, elastic [erals into granite, gneiss, and mica-slate, into vapors raise either single parts of the crust of the trachyte, basalt, and dolerite, independently of earth into dome-shaped, unopened masses of fels- present climates, and under the most dissimilar pathic trachyte and dolerite, (Puy de Dôme and zones, is still the same; so do we everywhere Chimborazo,) or the upheaved strata are broken observe the same laws of formation proclaiming through, and inclined outwards, in such wise, that themselves in the realm of inorganic nature, laws upon the opposite inner aspect a steep rocky edge according to which the strata of the crust of the is produced. This edge then becomes the boundary earth stand in a certain relationship to one another, of a crater of elevation. When this has risen from and under the influence of elastic forces, break the bottom of the sea, which does not, by any through one another as dikes. This recurrence means, happen in every case, it then determines of the same phenomena is particularly striking in the whole of the characteristic physiognomy of the volcanoes. When the navigator, among the islupheaved island. This is the origin of the circular ands of distant seas, finding himself surrounded form of Palma, which Leopold von Buch has de- by palms and strange forms of vegetation, and no scribed so carefully and so ably, as well as of longer sees the same stars, in the individualities Nisyros, in the Egean Sea. Occasionally, one- of the landscape, he still traces the characters of half the ring-like edge is destroyed: and in the Vesuvius, the dome-shaped summit of Auvergne, bay which the sea that has flowed in then forms, the crater of elevation of the Canaries and Azores, the social coral polypi establish themselves, and the fissures of eruption of Iceland repeated and produce their cellular dwellings. Craters of ele- reflected. A glance at the attendant of our planet, vation on continents are also frequently found the moon, generalizes still farther the analogy of filled with water, when they contribute to beautify formation here adverted to. In maps of the moon, the landscape in a peculiar manner. we observe in our satellite, without atmosphere and without water, vast craters of elevation, which surround conical mountains, or support them on their circular walls; unquestionable effects of the reaction of the interior of the moon upon her exterior, aided by the influence of diminished gravity. If, in many languages, volcanoes are properly designated Burning Mountains, it would still be a great mistake to suppose that they were produced by any gradual accumulation of the streams of lava that have flowed from them: their origin appears to be much more generally the consequence of a sudden upheaval of tenacious masses of trachyte, or augitic rock, including polychromatic [Labrador] felspar. The measure of the upheaving force reveals itself in the height of the volcano; and this is so different, that in one case it is a mere hillock (as in Cosima, one of the Japanese Kuriles ;*) in another, it is a cone that rises to an elevation of 18,000 feet. It has seemed to me as if the relative height had a great influence upon the frequency of the eruptions; as if these were much more common in the lower than the loftier volcanoes. I will call attention to the following series:-Stromboli, (2175 feet high,) GuaA proper valcano only arises where a perma- camayo, in the province of Quiros, which thunders nent connection is established between the interior almost every day, (I have frequently heard it in of the earth and the atmosphere. Here the reac- Chilo, near Quito, at a distance of 22 German tion of the interior upon the exterior proceeds for miles,) Vesuvius, (3637 feet high,) Ætna, (10,200 lengthened periods. It may, as in the case of feet high,) the Peak of Teneriffe, (11,424 feet Vesuvius, (Fisove,) be interrupted for centuries, high,) and Cotopaxi (17,892 feet high) If the and exhibit itself anew with renovated vigor. In focus of these several volcanoes be at the same the time of Nero, it was already customary, in depth below the surface, a greater force will be Rome, to rank Ætna among the number of the required to raise the molten masses to a six or gradually expiring volcanic mountains; Ælian, eight times higher level. Whilst the low Stromindeed, at a later period, maintained that the sea- boli (Strongyle) has labored incessantly, at least men began to see the sinking summit at a less dis- since the times of the Homeric traditions, and tance on the high seas than formerly. Where the serves as a light-house to the Tyrrhenian Sea, evidence of the eruption-I might say the old scaf-guiding the seaman with its fiery signal on his folding-has been perfectly preserved, the volcano course, the more lofty volcanoes are characterized shows itself rising from a crater of elevation; there by lengthened periods of repose. The eruptions a high rocky wall, a rampart of greatly inclined of the greater number of the colossal volcanoes strata, surrounds the isolated cone in the manner that crown the Andes, occur at intervals almost of of a circus. Sometimes there is not a trace of this a century apart; where exceptions to this rule circus-like enclosure visible; and the volcano, not have been observed-and I long ago directed always conical in figure, then arises as an elon-attention to them-they may probably be connected gated ridge immediately from the elevated plat- with the circumstance, that the communication form. This is the case with Pichincha, at the between the volcanic focus and the crater of erupfoot of which stands the city of Quito.

As the nature of mountain rocks, in other words, the combination or grouping of simple min

*Vide Jameson's Edin. Phil. Journal for an interesting account of Cosima, communicated by Tilesius.

tion is not, and cannot be conceived to be, equally or permanently free in every volcano at all times. In the less elevated volcanoes the channel of communication may be closed for a season; so that their eruptions become rarer, without their being, on this account, any nearer to extinction.

The

The crater which, except in very rare cases, occupies the summit of the volcano, forms a deep, and often accessible, basin-shaped valley, whose bottom is subject to incessant changes. greater or less depth of the crater is, in many volcanoes, an indication of the proximity or remoteWith the consideration of the relation between ness of an eruption. In the basin-shaped crater, the absolute height of volcanoes, and the frequency extensive fissures open and close again alternately, of their activity, in so far as this is externally visi-through which vapors of various kinds find vent, ble, the place at which the lava flows out is closely or small, rounded, and fiery openings, filled with connected. Eruptions from the crater are ex- molten matters are seen. The floor rises and falls, tremely rare in the case of many volcanoes; they and in it are formed hillocks of ashes and cones of generally proceed from the lateral fissures, (as no- eruption, which occasionally rise high above the ticed by the celebrated historian, Bembo, in the edges of the crater, and give the volcano its charsixteenth century, whilst yet a youth,) at places acteristic physiognomy for years; but, on the ocwhere the flanks of the uplifted mountain, in con- currence of fresh eruptions, they sink suddenly sequence of their shape and position, offer the least down and disappear. The openings of these cones amount of resistance. Upon these fissures cones of eruption, which rise from the floor of the crater, of eruption are occasionally raised. The larger of must not, as is too frequently done, be confounded these are of such dimensions that they are often with the crater itself, which encircles them. When erroneously designated by the title of new volca- the crater is inaccessible, from its vast depth, and noes. Ranked side by side, they show the direc- the perpendicular inward slope of its sides, as tion of a fissure which has again become closed: in the case of Rucu-Pichincha, (14,946 feet high,) the smaller ones frequently occur in groups, close-one can still look down from the edges upon the ly set together, and cover whole districts, as it summits of the monticules which rise within the were, with bell-shaped, or beehive-like, elevations. cauldron-like crater, partially filled with sulphureTo the latter class belong the hornitos of Jorullo, and the cone of the eruption of Vesuvius of October, 1822, of the volcano of Awatscha, according to Postels, and of the lava field near the Baidare mountains, in the peninsula of Kamtschatka, according to Erman.

When volcanoes do not rise free and isolated from a plain, when, on the contrary, they are surrounded by table-lands from 9,000 to 12,000 feet high, as in the double chain of the Andes of Quito, this circumstance may very well give rise to the fact that the most violent eruptions, when red-hot ashes and scoriæ are thrown out with detonations that are heard for hundreds of miles around, are never accompanied with streams of lava. This is the case with the volcanoes of Popayan, of the lofty plains of Los Pastos, and of the Andes of Quito; the single volcano of Antisana, among the latter, perhaps excepted.

ous vapor. A more wonderful or grander natural
prospect I have never enjoyed. In the interval be-
tween two eruptions, the crater of a volcano may
exhibit no luminous phenomenon, but merely open
fissures and jets of watery vapor; or hillocks of
ashes, that can be approached without danger, are
found upon its scarcely-heated bottom. These
often gratify the wandering geognost, without
making him run any risk, by casting out glowing
masses, which fall on the edges of the cone of sco-
riæ, their appearance being regularly announced by
slight, and entirely local, shocks-earthquakes on
a small scale. Lava occasionally flows from open
fissures, or small fiery gorges, into the crater itself,
without bursting through its walls, or overflowing
its edges. But if it does break through, the mol-
ten spring generally flows smoothly, and in such a
determinate direction, that the great cauldron-like
valley, called the crater, can still be visited during
the period of the eruption. Without a particular
description of the form, and also of the normal
structure of burning mountains, phenomena cannot
be rightly comprehended which have been distorted
by fantastical descriptions, and the various signifi-
cations attached to the words, Crater, Cone of
eruption, and Volcano; or rather, to the indefinite
and indeterminate use of these words. The edges
of the crater sometimes show themselves much less
liable to change than might be expected. A com-
parison of De Saussure's measurements with my
own, yields the remarkable result, in connection
with Vesuvius at least, that the northwest edge of
the volcano, the Rocca del Palo, may be regarded
as having remained for forty-nine years (1773-
1822) almost without change in its elevation above
the level of the sea. Any difference that appears.
may be looked on as within the possible errors of
measurement.

The height of the cone of ashes, and the dimensions and form of the crater, are the elements in the figure of volcanoes which more particularly impress upon each of them an individual character; but of these elements, both the cone and the crater are perfectly independent of the magnitude of the whole mountain. Vesuvius is not one third of the height of the Peak of Teneriffe, yet its cone of ashes forms one third of the whole height of the mountain, whilst the cone of ashes of the peak is only one twenty-second of the entire elevation. In the case of another volcano of much greater height than the peak, that of Rucu-Pinchincha, namely, the relations come nearer to those of Vesuvius. Of all the volcanoes I have seen in either hemisphere, Cotopaxi is that of which the conical form is the most regular and beautiful. A sudden melting of the snow of its cone of ashes indicates the proximity of an eruption. Before there is even any smoke visible in the attenuated strata of the Volcanoes whose summits reach far above the atmosphere that surround the summit of the cra- limits of perpetual snow, like those of the Andes,. ter's mouth, the walls of the ash-cone are some-present a variety of peculiar features. The sud-times heated through, when the entire mountain presents the most threatening and ill-omened aspect.

den melting of the snow in the course of an erup-tion, not only occasions destructive floods, torrents in which heaps of smoking ashes are floated! away on blocks of ice; but the accumulation of ice. *French feet in this and every other instance in the and snow goes on producing its influence uninter-. present paper.

ruptedly, and by filtration, into the trachytic rocks,.

From the Edinburgh Philosophical Journal.

On the Diluvial Epoch.

THE examination of a considerable number of fossil bones from the caves of France, and of the bones found in the gravel of the environs of Geneva, as well as a comparison of the different memoirs published on the organic remains of the diluvial epoch, have led me to form a different opinion from that generally entertained on this subject.

I find a second proof in the caverns and breccias By Professor F. J. themselves. Some species are there met with PICTET of Geneva. which I believe to be extinct, such as the bears of the caverns, the hyænas, and some others; but there are also found bones of a larger number of species, which cannot be distinguished from those now living in Europe. The bats, the shrews, the moles, the badgers, the hares, &c., of the caverns, appear to be identical with our own. Is it probable that they should all have differed from the species now living in their external characters, and that, having been destroyed en masse by diluvial The diluvial formation is commonly regarded as inundations, they should have been replaced, by separated from the modern epoch by characters as means of an entirely new creation, by species decided as those which distinguish the three divis-which we are not able to distinguish from them? ions of the tertiary period. The naturalists who I am of opinion that the following is the order believe absolutely in the peculiarity of the species of events as they occurred in Europe :-The speof the different formations (and, for my own part, cies now living, and some others, were created at I am of opinion that everything tends to show the commencement of the diluvial epoch. Partial that this law is to be considered as demonstrated) inundations and changes of temperature caused think that the order of events was the same in the some of them to perish, such as the mammoth, the diluvial epoch as in the others; that is to say, that species of bear having an arched forehead, the at the end of that period all the species became hyenas, the stag with gigantic horns, the rhinoce extinct, and that a new creation repeopled the ros, the hippopotamus, &c.; but the greater numearth at the commencement of the modern epoch.ber of the species escaped these causes of destrucThe study of the facts does not appear to me to justify this conclusion; and, on the contrary, I think that the diluvial epoch ought to be united with the modern epoch. I believe that there was no new creation, and no interruption of organic life, between the time when the bones of bears were buried in caverns and the present period. Let me, in a few words, adduce my reasons for taking this view of the subject, and then point out what I imagine actually occurred.

The first proof I shall give is derived from the study of the arenaceous deposits in the neighborhood of Geneva. These deposits have been very properly divided into two portions by M. Necker -the upper, termed diluvien cataclystique, and containing erratic blocks, rolled pebbles, and sand, irregularly stratified; and the lower, or alluvion ancienne, composed of pebbles, more equal in size, and more regularly arranged in beds, so that we may suppose that they were deposited by a more gentle and more tranquil agent than that by which the upper member was formed.

This ancient alluvium covers all the bottom of the valley without ever reaching the summit of the acclivities of the Molasse: it could not have been deposited except under circumstances very different from those existing at the present day, and it has altogether the characters of the deposits of the diluvial epoch.

tion, and still live. Besides those which I have mentioned, and others which I have noticed in the body of my work, it is possible, for example, that the Ursus priscus may be the original of recent bears, &c.

It may be objected, perhaps, that there is nothing, in this manner of viewing the subject, to account for the late appearance of man. It must be remarked, however, that it is necessary to distinguish between the creation of man and his establishment in Europe. It is probable that he did not arrive there till after the inundations which destroyed the cavern-bears and the contemporaneous animals. It may even be supposed that the last diluvial deposit, and, in particular, the arenaceous formations of Switzerland, were formed before the human species inhabited our regions. There is nothing, however, to prove that man had not been created in Asia at the commencement of the diluvial epoch. It must be remembered that the Sacred Writings, and the traditions of various nations, authorize us to believe that man witnessed some of those great inundations which were entitled to the name of deluges. Subsequently, tribes of the human race became more numerous, and migrated to Europe; and every one knows that philological, historical, and physiological researches all combine to demonstrate that Asia was the cradle of the nations which have successively invaded our continent.

Now, in these ancient alluvial deposits, bones are found which prove that our valley was inhabLastly, it may, perhaps, be said that this idea ited at that epoch by species of mammalia perfectly is opposed to the theory of the peculiarity of speidentical with those which now live there. We cies in each formation, and to that of successive can detect in these bones no difference of size or creations. I do not think so, for the question of form which can authorize the establishment of any new species. On the other hand, in the bed of the Allondon, that is to say, probably in a formation of the same epoch, a tusk of an elephant has been found.

These ancient alluvial deposits are probably contemporaneous (or nearly so) with those which exist in various other parts of the Swiss plain, and in which there have been found species now living, as well as remains of elephants.

These facts seem to me to show that the mammoth lived along with species identical with those of the present day, and to prove that there was no new creation between the deposits of which I have been speaking and those of our own period.

remains untouched as respects all the anterior epochs. But even though the result of this manner of viewing the subject should be to place in doubt the theories which I believe to be at the present moment the least inadmissible, I cannot, on that account, refuse to adopt an explanation of facts which seems to me evident. The state of theoretical paleontology is still too uncertain to allow of our attaching ourselves too strongly to this or that hypothesis. It is the study of facts which is essential, and we must engage in that study unbiassed by preconceived ideas or particular systems.*

* From Traité Elémentaire de Paléontologie, vol. i., p. 359. 1844.