which followed throughout the month. Its soil appeared on the point of being torn up by force, many buildings were destroyed, and its inhabitants fled in consternation to find an asylum in the country. The immense clouds of smoke and earthy ashes which were ejected from June to October; which covered the more lofty part of the mountain with a gray stratum; which filled the atmosphere and gave out through the whole region a strong odour of sulphur, clearly prove, that all these commotions were produced by forces collected in the recesses of Etna.*

While Nicosia and the whole space between Madonia and Ætna were in such commotion, Sicily to the West and all the northern coast enjoyed perfect quiet; but a sad reverse was preparing. In October Etna ceased throwing out sulphurous ashes and sand, and with it ceased all its noises, and shocks, and all was calm. In February in the beginning of the next years, small motions of the earth were felt along the northern side of the island, which were the preludes to the scene that presented itself in March.

The direction of the motion was from N. E. to S. W. as was proved by all the phenomena mentioned in the beginning.

*From June to October 1822, Ætna emitted great quantities of volcanic ashes which were scattered all over the mountain; on the plain about the crater it fell to the depth of a foot. From the mouth of the crater and through fissures near the mouth, so dense a smoke and such copious streams of aqueous vapour were given out, that when they were condensed by the lower temperature of the air, the ground about these orifices was drenched with water. The vapour which was still suspended by the caloric imparted to it by that already condensed, fell soon after in the form of a brine, acidified by the mixture of sulphurous vapour contained in the smoke, and to which was owing the odour of sulphur given out by the ashes wherever it fell. All the ashes about the crater was saturated with this brine. The vapour of water is always found in the smoke of Etna, but in much greater quantities at the time of an eruption. In my relation of that of 1792, I mentioned, that at a little distance from the crater a new orifice was made by the force of the vapour, from which for a long time, pieces of old lava, and scoriæ, and argillaceous earth saturated with water, were ejected; that standing there to observe it, I was continually bathed in the brine which fell from the smoke. This phenomenon of Ætna in 1822 has been much altered in foreign Journals, which say, that in the recent eruptions of Etna, the earth opened at a great distance from the crater, and that a muddy substance which is not lava, was thrown out. As this important error, should it gain credit, would be injurious to science, I make all haste to correct it. In 1822, neither at a great nor at a small distance from the crater, the earth opened and the matter thrown out is volcanic ashes, perfectly like that which has usually been expelled by this volcano; at least for the forty years that I have studied it. It did not come out in the form of mud, but in exceedingly fine dust, which afterwards became wet with the vapour condensed within the very edges of the fissures, or which fell in brine. It is a long while since any of the writers on volca. noes, wishing to establish the theory of " eruptions of mud," have named that

I will not be guided by the injuries suffered in different parts, for these spring from a complication of causes; from the soil, its greater or less capacity of receiving and communicating motion; from the manner in which it presents itself to the progressive motion, and from the state of the edifices. These circumstances may sometimes produce anomalies which easily deceive those who do not bestow in the examination of them the attention which they deserve; but without fear of error I may say, that in general the shock was much the most forcible on the northern shore, and at a little distance from it; and that it went on gradually diminishing towards the interior. The moving force, then, must have been in operation somewhere under the sea opposite this part of the Island. Naso was almost entirely ruined; Patti, and all the towns about Capes Orlando and Calava, and which are nearer Eolia were considerably damaged. Some very small, thinly inhabited towns lost little because they had little to lose; others were in some measure defended by their situations. Palermo, at the bottom of a bay which curves towards these burning islands, and surrounded by large and high mountains on the other side, was exposed to the whole force of the motion against it; this

of sea water and shells in 1755; a popular credulity, which I have been compelled to do away, by every possible proof. This new error of 1822 might recall their arguments and lead on to other errors. I have given with much pleasure, a true detail of the fact to the illustrious M. de Humboldt, who wrote me on the subject, with that ardent zeal which characterizes him, and which has rendered him, as he is proclaimed in both hemispheres, one of the greatest observers of nature. With respect to the nature of this volcanic ashes, although I am convinced that it differs not at all from that which has always been ejected, yet I wished to consult the oracle of Chemistry upon it, since it is his delight to discover the composition of bodies; I mean the illustrious Vauquelin, whose noble interest in me has conferred on me so much honour. My first packet, much to my regret and that of the eminent chemist who was expecting it, never reached its destiny; but I renewed it, and the results shall have place in my continuation of the history of Etna from 1818 where I left it, which I shall soon publish. I will add to finish this note, that the "muddy eruptions" so called by our Macalubbi are not such, even according to the imaginary ideas of Plato, who admitted rivers of mud in the interior of the globe, to which end he alledged such eruptions in Sicily. Nothing comes up from the depths of the earth but streams of carburetted hydrogen gas, which finding above, the argillaceous chalk, of which the soil is formed, loosened away by rain water, it forces it up and canses it to flow in muddy streams. In times of drought, dust only is forced up, and in its passage a whistling is made like an impetuous wind. Even of our Lake of the Palici, they believe that the water comes from the interior of the earth, and wonder that it never overflows. Why do they not observe that in dry years it entirely evaporates, and that nothing comes out of the chinks at its bottom but currents of air, which give to the water the appearance of boiling when it collects there from the rain.

it was, together with the degraded state of its buildings, which brought such ruin upon this beautiful city. Every thing seemed then to announce to us, that the most expansive vapours which proceed from the burning furnaces of Eolia, in developing their immense volumes, urged against the sides of those cavities which once contained the matter of which all these islands are formed, produced the motion that struck obliquely against Sicily, and moving along the shore towards the west, spread despair throughout Palermo. After the shock of the fifth their motion was more free; and they were heard murmuring under the soil near our island, seeking an outlet from the obscure caverns in which they were generated, but not propagating their motion to any considerable distance. The course of that of the seventh was in the same direction with that of the fifth; but that of the thirty-first was in a direction directly opposite, since it was felt at Messina, and not at Palermo. The undulations were determined by the horrizontal direction of the motion; the perpendicular shocks, by a force acting from below upwards, which supposes a much greater depth in the situation of the acting force, than the other, without ever being in any case nearer the surface. Every one may easily distinguish the difference which subsists between the superficial motion caused by the rapid passing of a heavy carriage, or by the sudden combustion of a large quantity of confined powder, which would cause the darting of a large accumulation of electric fluid to restore the equilibrium between the earth and the atmosphere, were it possible for it to collect in the midst of so many conducting bodies which seem designed to restore the equilibrium instantly ;between this motion, and the deep, heavy earthquake; armed with such terrible power; which agitates so violently a great extent of the globe; which sometimes seems ready to tear it from its very foundation, and which has all the characters of an effect sprung from most wonderful degrees of force and of force, which placed deep in the earth, moves and convulses those great masses lying between it and the surface.

The idea of forces and effects like these, fills with fear the miserable mortal who creeps upon the face of the earth, and brings his pride down to the dust. When he sees the earth reel, and the great fabricks which he has raised with so much confidence, rushing to ruin, he despairs of finding any where one firm support to his frail existence.

The chinks and fissures formed in many places, and to which the vulgar attribute much importance, are in consequence of the quaking of the soil, and to which the softness of the

earth and the loss of its internal support have given place. The country of Bosco about Ogliastro, of which I have already spoken, became furrowed with diverse, long, tortuous, deep clefts, the sides of which in some places sunk down; in other places, portions of the surface passed down over inclined plains below them, and took new positions; the olive trees, which some of these carried with them, were much injured by the breaking and displacing of their roots. This land is formed of an immense deposit of argillaceous chalk, more than a hundred feet deep. The water which penetrated it, and the winter there was very rainy, loosened away the earth, and carried a great part of it into the internal cavities below; the surface thus wanting solid support, under the shock of the earthquake became filled with depressions, caverns, and inequalities. The same may be said of a great aperture made in the vicinity of Colesano, which dilating itself day after day threatened to render those places inaccessible. Copious showers alone produce such effects in the chalky land of many parts of Sicily. This want of firm bases frequently causes the overthrow of great rocks at the time of earthquakes. Well do we remember, that in the earthquake of the fifth of February 1783, a mountain, a mile to the south of Scilla, and which was a mile and a half in length, fell over into the sea of Calabria and formed two new promontories.

Phenomena observed in the Eolian Sea.

If all these facts induce us to locate in Eolia the causes of the physical events of the past March, it is necessary to inquire if these islands exhibited at that time, any phenomena, which may corroborate our opinion. I will mention, therefore, in this place many facts, about which there can be no uncertainty, and which will be of the greatest importance should any one wish to push the suspicion which I have announced in this memoir, to certain evidence.*

Since September of last year, the daily quantity of smoke from Vulcano, has been much greater than usual; and flame

The external phenomena of a volcano, show that the effects of the fer mentation have come to the surface; but nature operates often in the dark recesses of the earth, without exhibiting any external visible effects of her operations; elastic vapours may form there, shake the soil, and return to their concrete state When eruptions happen from the inflamed mouths, it is because these subterranean forces have met with substances which may be thrown out, thus giving certain proof of the existence of these forces.

has often been visible in the evening. Explosions have been frequently heard on the neighbouring coasts of Sicily. But Stromboli has exhibited the greatest activity for almost fourteen months without intermission. Shocks have been very frequent, and so strong as to fill the islanders, although accustomed to them, with great apprehensions. The island, with the blazing mountain itself, seemed often on the point of being torn up from its foundation. The volcano opened two new mouths on the side which looks towards the sea, and belched out from them fearful clouds of sand, and burning rocks, which after darkening the air, fell to the earth. Fortunately their direction was not towards any of the little habitations, or cultivated fields of the island. One forest only on the side of the mountain, suffered some injury. The inhabitants often found themselves enveloped in thick clouds of black smoke and ashes, which the wind drove among them. But only one man was struck by the burning rocks hurled through the air with immense violence. The scoria and ashes did much damage to the cisterns of the island, and to the terraces which serve as tiles over thera. Torrents of black smoke, ashes and sand were often ejected and thrown to various distances. The greatest shocks were sometimes followed by a thick dry cloud, which filled the air of the whole island.

The shock of the fifth of March was very strong at Stromboli, at Saline, formerly Didime, and at Lipari. The inhabitants of Lipari did not doubt that their houses would this time be reduced to ruins; and they have not yet ceased giving thanks to heaven and their protecting Saints, for defending them from utter destruction. They affirm that a moment after the shock, all their thoughts were turned upon the disasters which might happen to places on the neighbouring coast of Sicily and at Palermo; towards which the direction of the motion seemed to be. Lipari lies between us and Stromboli. Since April the parts of our island which were before agitated, have been left in repose; but shocks are still frequent at Stromboli, and keep the poor inhabitants there in continued fear. The subterranean furnace seems to have lost much of its power, as the elastic vapours generated there shake but a very limited space, and the new apertures of the mountains, emit now and then but a very small quantity of fine sand, which is always the last product of an expiring conflagration.

From what I have laid down it is just to conclude, that the fires of Eolia are those which have for a long time been preparing the event of last March; that it was produced by motions generated in those mighty furnaces, and that those mo