Count Borch, however, the chief advocate of the opi nion which we are now combating, produces several facts greatly in favour of his own hypothesis. He in forms us, that he examined, in 1776, lavas of the follow ing different periods-1157, 1329, 1669, 1766. The first had acquired a coating of earth 12 inches thick ; the second, one of eight inches ; the third, more than one inch ; and the last was entirely destitute of soil. Here the series is perfectly regular, and the quantity of soil formed corresponds exactly to the age of the lava ; but the Abbe Spallanzani very pertinently inquires, If the lava which flowed in 1529, and was examined by the count 447 years after, had acquired a covering of earth eight inches thick, how does it happen that the lava of the Arso in Ischia, which flowed in Is02, appcared, in 1788, to preserve its original hardness and sterility The argument derived from the appearance of the pit at Jaci, has no force, unless it can be demonstrated, that the thickness of the beds of vegetable earth corresponds exactly to the period between the eruptions. But it must appear pet lectly nugatory, if it can be shown, that an appearance exactly similar has been produced within the limits of authentic history. The ruias of Hercula neum furnish us with a fact of this kind. Tie.. cruption which overwhelmed this once flourishing city, is renown to have happened in the reign of Titus, little more o.ao 1700 years ago. Upon examining the ruins, it is lointd that six different eruptions have occurred since that pe riod, and that each of the strata of lava is separate a by buds of rich soil.
We shall now conclude this article with an account of the different eruptions recorded by historians, Spa ;an zini estimates the whole number which have happened within the limits of authentic history, to be about 51, of says Giocni, not more than 10 have issued hunt the highest crater. It is happily a matter of small mo ment; otherwise it might afford considerable difficulty to determine the precise number of eruptions which have happened, even within this period. The same eruption is often renewed, after a considerable interval ; and this expiring effort may sometimcs be mistaken by the passing spectator for the commencement of a new eruption. Sonic begin to entertain the opinion that AtItna has now nearly exhausted its force, and that its eruptions are not so frequent, or of such magnitude as in former ages. flow Far this opinion is consistent with facts, we pretend not to determine ; but certainly it is reasonable to suppose, that every new eruption, by di minishing the quantity of volcanic matter, or by remor ing it. farther from the focus, and thus rendering it more difficult to be elevated ; by excavating the moun tain, and enlarging its caverns in such a manlier as to diminish the effect of the vapour, must ultimately tend to lessen the number and violence of the eruptions.
The phenomena attending an eruption have been fn. quently and minutely described by different authors.. The pale white smoke, which continually issues from the crater, even in its quietest state, begins to increase in quantity ; small clouds of black smoke are seen at short intervals, shooting up through the centre of the white column, and suddenly losing themselves in the higher regions of the air. Tiles... clouds soon increase in num ber, and at last the whole column assumes a black ap pearance. During the night, this black smoke resembles a pillar of flame ; an appearance which the lowest part of the column retains even during the day. This smoke becomes highly electrical ; and continual flashes of forked lightning are seen darting from it in every direc tion. In this state it is sometimes carried by the winds into the adjoining country, where it commits the most dreadful ravages. Mr Brydooe informs us, that on some occasions it has been known to extend to a distance of 100 miles, laying waste every thing around, killing the shepherd and his flocks on the mountains, blasting the trees, and setting fire to the houses. In this state of the mountain, showers of ashes frequently occur, earth quakes are produced, and red hot stones are projected to a great height in the air. Brydone states, upon the authority of Recupero, that stones of immense size have sometimes been thrown upwards to the height of feet.
These app( al:dices genet ally continue for three or four months, after w Inch the lava begins to boil over the top of the crater, or bursts from sonic part of the side. The violent commotions of the mountain now cease, and the lava flows down its sides in a regular stream. Sometimes, however, the opening proves too for the full discharge of the lava, and then the mountain rages with increased fury ; nor is tranquillity restored, till, by bursting asunder the barriers, a free vent is given for the discharge. During the night, the lava appears like a stream of fire, and in the day -time is easily recognised at a distance, by the white smoke w hich constantly hovers over it.
The great features of an eruption of 'Lana arc thus delineated by Virgil, in the third book of the Encid : Ilorrificis jtotta tonal ..Etna Interdumque strain prorumpit ad zetbcra nubem, Turbine linnantem picco et candente t'a ilia Adtollitque globos flammarum, et siklerslarnbit: Interdum scopulos, avolsaque viscera montis Erigit eructans, liquelactaque saxa sub auras Cum gemitu glomerat, fundoque exzestuat imo.
The first eruption recorded in history, is that men tioned by Diodorus Siculus, (lib. v. tom. 1. p. 335.) He does not fix the date, hut informs us, that in consequence of this eruption, the Sicani abandoned the eastern side of Sicily, which was afterwards occupied by the Sici lians, a colony from Italy. Thucydides relates, that Etna, at three different times, discharged torrents of fire, be tween the third year of the 11th olympiad (733 A. C.), and the third year of the 88th olympiad (425 A. C.) See Thucydides, b. iii. c. 116. The second eruption, or the first mentioned by Thneydides, happened, according to Eusebius, 565 A. C. The third eruption, or the second of Tnucydides, happened in the same year in which Mardonius was defeated at Platcea, or the second year of the 75th olympiad (476 A. C.) Both the victory and the ruption are commemorated in an inscription on the Oxford Marble. This eruption is distinguished by an act of filial piety, the memory of which the inhabitants of Catania consecrated by a temple; and succeeding historians have preserved in a record still more durable. See Straho, tom. i. p. 412. Silius Italicus, lib. xiv. p. 03. Valerius Maximus, lib. v. c. 4. Seneca, Aristo tle, Claudian, &c. This was no other than a bold and successful attempt of two Sicilian youths, Amphinomus and Anapis, to rescue, at the hazard of their own lives, their aged parents from the devouring flames. The burth eruption, or the third mentioned by Thucydides, occurred in the 88th olympiad, A. C. 425. The fifth happened in the consulship of Sergius Fulvius Flaccus, and Q. Calpurn ins Piso (133 A. C.), according to Oro Livy mentions an eruption in the consulate of C. Larlius and Q. Scryilius, A. C. 140. The sixth eruption
happened 125 A. C. ()rosins relates, that a prodigious quantity of fishes were destroyed by it, and that the in habitants of Lipari suffered exceedingly by eating them. The seventh eruption occurred 121 A. C. In conse quence of the damage occasioned by this eruption, the inhabitants of Catania were excused by the Romans from paying taxes for 10 years. Sec Livy, lib. lxi. c. 41. Thc rig hilt eruption happened 43 A. C., and was regard ed by some as ominous of the death of Cxsar. The .:inth eruption happened .10 A. D., and caused Caligula fly precipitately from Messina. Carera mentions two eruptions ; one in the year 253, and another in In the reign of Charlemagne, 812, another eruption hap pened. Geoffrey of Viterby mentions it in his Chronicle. In 1169, Sicily was disturbed by a violent earthquake. Catania was destroyed by it, and 15,0)0 persons perish ed. On this occasion, old rivers disappeared, and new ones burst out, and the ridge of Etna fell in on the side near Taormino. The spring of Arethusa became mud dy, and the fountain of Ajo ceased to flow for two hours, and then gushed out more abundantly than before. The sea retired within its usual limits, and then overflowed its ordinary banks, and swabowed up a number of per sons who had fled to the shore for safety. Corn and trees of all sorts were destroyed, and the fields were covered with stones, so as to become unfit for cultivation. In 1181, streams of fire, we are told, ran down the declivity of the mountain. In 1329, the inhabitants of Sicily were alarmed by the noises of Etna. A terrible blaze of fire issued from the southern summit, accompanied with huge stones, The fire and ashes spread to a con siderable distance, laying waste the neighbouring fields, destroying the buildings, and occasioning the death of birds and quadrupeds, and the fishes of the rivers. 'rhe ashes were carried as far as Malta ; and many persons are said to have died of terror. Eruptions, attended by no remarkable circumstances, happened in the following years, 1333, 1381, 1444, 1446, 1447 ; but after a cessa tion of near 100 years, an eruption occurred in 1536, which was dreadful in its appearance and effects, and which lasted a considerable time. A thick cloud, tinged with red in the middle, hovered over the summit of the mountain, which was attended by a strong west wind, and succeeded by the discharge of a large quantity of burning materials, that rushed, like a torrent, clown the eastern side of the mountain, destroying every thing that came in its way. A similar stream directed its course to the west, and did great damage. Chasms were opened on the sides of the mountain, from which streams of ignited matter were thrown up to a great height in the air. A learned physician, led by curiosity to examine this eruption, was burned to ashes by a volley of burning stones. Etna continued in this state, with little inter ruption, for a whole year. The eruption ended with the overflowing of the river Simetus. The effects of this inundation were peculiarly disastrous. The country in the neighbourhood of Paterno, the adjoining castles, and more than 500 houses, presented one scene of ruin and desolation. The people who lived on its banks, with their cattle, and all their property, were seen floating down the stream. On this occasion, the gardens and vineyards of .Vicolosi and St Niccolo dell' .1rena were laid waste by the torrents of lava which issued from the sides of the mountain, earthquakes were felt throughout the whole island, and the summit of Etna fell in with a tremendous noise. The inhabitants were so much alarm ed and distressed, that they wore mourning during the greater part of the year. In 1567 and 1579, the ravages of /Etna were renewed ; and from 1603 to 1636, its eruptions were occasionally repeated, and torrents of lava flowed from it, which destroyed the woods and vine yards within their reach. In 1650, Oldenburg informs us, that the mountain burnt on the north side, and pro duced great devastation. Carera relates, that he was witness of a dreadful conflagration in 1664, which lasted for several years. But of all the eruptions, that of 1669 was the most formidable and destructive. It was pre ceded for eighteen days with a dark sky, thunder and lightning, and frequent concussions of the earth. The old crater of /Etna, and the neighbouring islands of Stromboli and Volcano, by their unusual commotions, gave signs of the approaching desolations. In the even ing of the llth of March, a chasm was opened on the east side of the mountain, 12 miles in icni th, and 5 or 6 wide, in the neighbourhood of Monte Rosso. On the following night, a new chasm was formed in the very place where the mountain now stands, together Is ith others in different parts of the mountain, from all of which there issued huge volumes of smoke. From the princi pal chasm a stream of lava proceeded, which directed its course to a lake called liardia, about six miles from Montepileri, destroying in its course the neighbouring village. The next clay, it laid waste Mal Passo and Montepileri. On the 23d of March, the stream was in some places two miles broad ; on this clay a new gulf was opened, from which were discharged sand and ashes, which formed a hid with two summits, two miles in cir cumference, and 150 paces high. This new mountain continued to discharge ashes for three months, in such quantity as to cover the adjoining tract of country for 15 miles. It is even said, that these ashes were carried by the winds as far as Calabria. On the 25th of March, the whole mountain was agitated by a iolent earth quake, the summit fell in, and a deep gulf was opened, more than a mile in extent, from which was discharged enormous masses of stones and ashes. It is said that the famous block of lava on mount Frumento was dis charged on this occasion. The torrent of lava which still continued to flow, directed its course to Catania. It passed over the walls, near the spot occupied by the gardens and convent of the Benedictines, and laid waste the greater part of the city. After this, it divided into separate channels, and proceeded towards the sea. For farther particulars, sec BortEw, and the account of the English merchants in the Phil. Trans. No. 51. ?lbr. vol. ii. p. 337. The following additional circumstances respecting this great eruption are related by lord Win •helsea, who at that time happened to be at Catania in his way home from Constantinople. The stream of lava in 40 days, destroyed the habitations of 27,000 persons. In its progress to the sea, it passed through a lake four miles in extent, and four fathoms deep, which it not only filled up, but formed into a hill. Ile says that at the distance of 10 miles, he saw the torrent begin to run down the mountain, and that the flame which accompa nied it, rose to a height equal to the highest steeples in England ; that as it descended the mountain, it appear ed of a fiery red colour, bearing on its surface stones as large as an ordinary table. Sec an extract of this account in sir W. Hamilton's Travels.