was not, upon the whole volcanic cone, an aperture of sufficient dimensions for the vent of an eruption. On the eastern side, indeed, there was an opening of about eleven feet in diameter, which continued to emit ashes and pumice stones;--and there was, besides, on the north side a smaller aperture which kept up an impotent eruption,-but was finally chocked and closed by its own vomitings. In May 1812, the emissions of the larger opening were accompanied by a very slight quake of the earth; but it passed off without much violence; and the atmosphere became clear, serene, and insufferably warm. The winter of 1813 was distinguished for an unusual quantity of rain and snow: yet in the middle of May, when the heat of spring had scarcely begun, signor Monticelli observed that the water in the chief wells of Naples had fallen upon an average between eight and nine feet. On the 17th of May and 9th of June,notwithstanding, as our readers know, there is no ebb and flow of the tides in the Mediterranean, the sea along the shores adjacent to Naples receded very suddenly to the distance of from ten to fifteen yards. During the months of June, July, and August, the west and south winds brought constant rains; yet the water in the Neapolitan wells continued to fall; and in that particularly which supplied the great fountain of Resina, the ultimate depression was no less than thirty-nine feet below the common level. During the whole of this period, too, the mountain itself gave evident signs of being in labour. Detonations, attended with slight oscillations of the earth, and followed by emissions of smoke, ashes, and flame, were repeated with increasing violence through nearly the whole of August; and on the 26th of that month a gigantic column of flame shot up from the crater, amidst reiterated explosions, and was blown by the fresh north east wind so as to wave towards Torre del Greco. For many successive nights the same phenomenon occurred; but the mountain was at length exhausted, and every thing about it once more became silent and calm.

During the occurrences of August the temperature of the air continually increased; and in one particular instance the mercury rose from 66° to 76° of Farenheit. The latter temperature continued till the 26th and 28th of October; during the caliginous nights of which two days the vivid flashes of lightning, the successive flames of the volcano, and the deep rumbling of the mountain, contributed to inspire the inhabitants with all the terrors connected with the apprehension of immediate death. Then came a heavy rain, mixed with hail; all became calm again; nor did any thing memorable take place for the space of nearly a month. On the 25th of December, however, the atmosphere became dense and black: the sum

mit of the mountain was concealed in an envelop of heavy clouds which had been accumulated by a strong easterly gale; and, towards ten in the morning, a few detonations, accompanied by the quaking of the earth, announced, too well, what was the event to be apprehended.' The wind soon after shifted a little to the north; the clouds were gradually dispersed;* the bellowings of the mountain became louder; and, at two in the afternoon, a most violent and deafening explosion was succeeded by a lofty column of dense black smoke, which soon filled the basin-overran-and was seen descending on all sides. In the mean time, too, the mouth of 1812 was doing its share by throwing out with incredible fury, and in every direction, smoke, ashes, and ignited stones.

Night added greatly to the sublimity of the scene. The torrents of lava which descended the mountain, and were occasionally obscured or hidden by the intervention of black smoke,--the huge masses of burning matter which leaped, and thundered down its sides, the showers of red-hot rocks, flints, and pumice-stones which were seen falling through the air, accompanied by the tremendous explosions which made the whole mountain tremble, and shook the largest houses in Naples, all contributed to overwhelm the spectator with terror, and to shrink him into a sense of his own littleness and impotence. A short respite was given to him by a calm;-but it was only to confound him the more by the eruption which followed. On the 26th all the phenomena of the preceding day were repeated with augmented violence; insomuch that the inhabitants of the subjacent villages were obliged to desert their houses in order to escape a deluge of consuming fire. By nine o'clock in the evening, however, the mountain was about exhausted; and nothing could now be seen, except a languid emission of black smoke, with showers of coarse volcanic sand. With some immaterial alterations the volcano continued in this state till the month of May, 1814; during the 9th and 24th of which there were showers of rain and red-hot sand, that destroyed vegetation whereever they fell.

Three days after the last violent eructation, signor Monticelli was enabled to attain the summit of the mountain; though even then his eyes were not a little annoyed by the volumes of smoke, and his nose by the strong smell of muriatic vapours. At intervals the surface of the cone was pierced with small holes; which, in consequence of their emitting smoke, were cal

We have here followed S. Monticelli's account of the matter:-but, for ourselves, we cannot conceive how a north-easterly wind should dissipate clouds which had been gathered by an easterly one.

led fumarole: the ground was covered with saline sublimations of various colours with perfectly crystallized modifications;' and here and there were large solid masses formed by the conglomeration of porous lava, pumice-stones, and scoriae, held firmly together by some tenacious substances.' Some of the sublimations were deliquescent; and the red and yellow in particular, furnished a reddish-yellow liquid which stained paper and the skin. It had an astringent taste-a muriatic smell-reddened litmus-paper-possessed an oily fluidity; and according to an analysis by professor Conti of Rome, was found to contain 20 parts of iron, 10 of alumina, 6.14 of lime, 9.97 of free muriatic acid, and 53.89 of water.-In April, 1814, signor Monticelli revisited the mountain; and was not a little surprised to find, that a smell of sulphurous acid, deeply affecting the fauces, had succeeded to that of muriatic acid, and that instead of the muriatic salts, the openings and fumarole still remaining, were thickly lined with sulphur and sulphate of lime.' Some lava, too, which the signor had before considered as grumous, was now found covered with crystallized oligistic iron; a circumstance which calls to mind (adds the Reporter, Mr. Granville) the curious facts which I lately had the honour of noticing, in my Report on M. Methuon's Memoir on natural cystallization.' We have turned back to the paper here alluded to, and, as it contains what, we think, may be new to mineralogists in this country, we shall make no apology for laying before our readers an abstract of the article.

M. Methuon, one of the chief engineers of the French mines, has published what he calls A Discovery of the Manner in which are formed earthy and metallic Crystals, not of a saline Nature; and pretendst o have devised an apparatus by which such crystals may be artificially obtained. He aims at overthrowing the system of Haüy; and his theory is, that crystals are not the immediate consequence of undisturbed solution or fusion; but are produced, in the dry way and in the open air, by the decomposition of amorphous crystallizable masses, the particles of which arrange themselves during the process, according to certain laws of attraction.-His facts are these. In a mineralogical excursion upon the island of Elba he came across a block of argillaceous shistus with pyrites,—which he found, upon examination, to be covered with several capillary crystals of alum from one-half to three-fourths of an inch in length. The rock was already decomposed to the depth of one and a-half of an inch; and, conjecturing that these two phenomena might be ultimately connected with each other, M. Methuon reared a shelter over the mineral and used frequently to go and watch the progress of its alterations. Every day the crystals grew

larger, and the decomposition deeper; insomuch that at the end of two months the size of the former was doubled, and the depth of the latter proportionally increased. As these saline crystals were evidently the result of a union between the argil of the rock and the acid formed by the contact of the atmospheric air with the sulphur of the pyrites, M. Methuon was struck with an idea, that the crystallization of earthy and metallic substances might be effected by a process somewhat analogous. Experiments were accordingly instituted; and the author finally succeeded in procuring earthy and metallic crystals in precisely the manner he had anticipated. He transported from Piedmont,-where he had been on a mission,-some crystallizable and shapeless masses of alaite, garnet, green idocrase, pyroxene, and amorphous pyrites; out of all which he composed a sort of artificial mountain on his chimney piece, and passed many anxious days and weeks in observing what it was likely to bring forth. At length he had the pleasure of seeing crystals of all these substances emerge from the heterogeneous mixture; small prisms of pyroxene appearing first, and afterwards in succession, the summits of crystallized alaite, and the planes of garnet, of idocrase, and of peridot.

His observations were equally successful:-and in one instance, indeed, he caught nature (says the reporter) in the very act of forming crystals of quartz on a mass of silico-calcareous earth. He had previously removed from the surface every sign of pre-existing crystallization, and left it for a few weeks to its own operations. Points of rocky-crystal first appeared; then the pyramidal summits; and finally the prism itself; the mass all the while diminishing as the crystal grew more and more diaphanous. The process continued; and at the end of three and twenty months there were on the rock six beautiful crystals of quartz from two-thirds to three-fourths of an inch in length and one-third in diameter; while the silico-calcareous stone around them was excavated in a like proportion. It is just to observe, however, that the rock was not continually dry; for though M. Methuon says it was beyond the reach of waves, he acknowledges that, in tempestuous weather, its exposed surface was often bedewed by the spray. His other observations were not so ambiguous. While in Piedmont he removed some indistinct crystals from an amorphous mass of alaite and garnet; and in the course of six years had the satisfaction of gathering a second and a third crop of new and beautiful crystals. He details a number of other observations and experiments which appear to be equally cogent; and then draws the general conclusions of his hypothesis, that the natural process of crystallization originally begins in a partial decomposition of the

surface of the crystallizable fossil; that from certain spots of this surface, when it has first begun, the decomposition proceeds in straight and narrow lines to other similar spots (somewhat, perhaps, like the incipient congelation of water), which in their turn, send forth similar lines, sometimes parallel to the former, at other times crossing each other at right, acute, or obtuse angles; thus dividing, or, more commonly speaking, carving or engraving the surface of the fossil into several compartments, which become, by a continuance of the process of decomposition, as many distinct pieces, constituting the body of the crystal in its rough state;--and lastly, that during the process, the substances of a different nature, contained in the mineral, separate, and arrange themselves, in one or more parts of the same compartment, the fossil mass continuing to be solid and hard, but fragil and easy to be broken; the author having often broken between his fingers, some, which had before withstood the strongest percussions.' As corollaries to the theory he insists, '1st, that crystals begin to form at their summit, edges, and solid angles: 2dly,-that nature produces, by a direct process, all simple and compound crystals, without first forming a nucleus in the latter: 3dly,-that the matter serving to form the crystals (called by himself, crystallizable matter), is in the state of a solid mass before, and continues in that same state during the whole process of crystallization: and 4thly,--that crystallizable matter is that which has filled, by infiltration, the chasms and clefts of mountains and the cavities of rocks; which composes the veins, the stilactites, and the stilagmitis; and, in general, all that which constitutes accidental formations found in blocks, nodules, &c. within large masses.' Such is the outline of M. Methuon's system; and it must be acknowledged, we think, to be pretty well supported by the facts which he has adduced. The author is said to be a person of unquestionable veracity:And even if he had made too favourable a report of his own experiments and observations, we have an account of similar ones in this country which, in conjunction with his would seem to establish the hypothesis upon a pretty sure foundation. In the neighbourhood of Boston there are crystallizations of feldspar in masses of sienite, which are attended by all the phenomena described by M. Methuon, and which have been considered by our own mineralogists as of more recent formation than the masses of which they constitute a part. It must be confessed, on the other hand, that some of M. Methuon's facts are rather contradictory of his hypothesis. It appears to us pretty evident, for instance, that the successive augmentation of the crystals which he caused to be produced, is little calculated to favour the supposition that they did not originate in a