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Mount Etna\n\nCategory:Mountains of Italy\n{| border="1" bgcolor="#ffffff" cellpadding="5" align="right" width="305" style="margin-left:3px"\n!bgcolor=#e7dcc3 colspan=2|Etna\n|-\n|align=center colspan=2|  Ash plume from 2002 eruption of Etna, photographed from the International Space Station\n|-\n|bgcolor=#e7dcc3| Elevation:||10,991 ft (3,350 m)\n|-\n|bgcolor=#e7dcc3| Latitude:||37° 44′ 3″ N\n|-\n|bgcolor=#e7dcc3| Longitude:||15° 0′ 16″ E\n|-\n|bgcolor=#e7dcc3|Location:|| Sicily, Italy\n|-\n|bgcolor=#e7dcc3| Range:||\n|-\n|bgcolor=#e7dcc3| Type:|| Stratovolcano\n|}\n
Mount Etna (or Aetna) is an active volcano on the east coast of Sicily (Italian Sicilia), close to Messina and Catania. It is 3,323 m (10,902 ft) high. On the safe part of its hills a famous wine is produced.
Appearance and height\nMount Etna is about three times higher than Vesuvius, rising to 3323m above the level of the sea, and about 140 km circumference at its base.
Recent eruptions\nEtna is highly active, and currently the volcano has an eruption every few years. The constant monitoring, and the relative tranquillity of these eruptions, mean that there is no danger to human life. But sometimes, the lava streams burn down houses and gardens. On at least one occasion, a big lava stream has been diverted to a nearby empty valley to protect a village, though others have been lost.
Ancient eruptions\nOnly vague records of Etna's ancient eruptions survive. The Greek poet Pindar is the earliest writer who makes mention of its activity. He refers to it in his First Pythian Ode of about 470 BC, Strophe B, 1. The eruption discussed probably took place shortly before that date, since when there have been about 60 (?) recorded eruptions.
According to Carey's translation of Pindar:
- From whose caverned depths aspire,\n:In purest folds upwreathing, tost\n:Fountains of approachless fire--\n:by day a flood of smouldering smoke\n:With sullen gleam the torrents pour
Virgil also describes the mountain very forcibly in the Æneid,\nlib. iii. 570. Dryden's translation reads:--
- ''The port capacious, and secure from wind,\n:Is to the foot of thund'ring Etna joined.\n:By turns a pitchy cloud she rolls on high:\n:By turns hot embers from her entrails fly,\n:And flakes of mounting flames, that lick the sky.\n:Oft from her bowels massy rocks are thrown,\n:And shivered by the force come piece-meal down.\n:Oft liquid lakes of burning sulphur flow,\n:Fed from the fiery springs that boil below."
Other Detail - requires heavy editing\nOwing to the great height of Mount Etna, the lava seldom rises so far as to flow from the summit. It more frequently bursts forth from the flanks of the mountain; and in this manner there have been formed numerous smaller cones, of which several have craters of their own. Hence Etna is rather a group of volcanoes than a single cone; but all these subordinate volcanic hills cluster round the flanks of the great central summit. Some of these hills are covered with forests and rich vegetation, having enjoyed a lengthy rest from further lava flows. Others are still arid and bare, having been more recently formed. Owing to this peculiarity in its structure, Etna does not present the conical aspect which characterizes many other volcanoes. There are caverns on the sides of the mountain, which the Sicilians used for storing ice before the invention of refrigerators. Some of these caverns are large; one, called Fossa della Palomba measures 190 m in circumference at its entrance, and has a depth of about 24 m. This great cavity, however, forms merely the vestibule to a series of others, which are perfectly dark.
Another striking feature of Mount Etna is the Val del Bove. It is a deep valley, presenting, when viewed from above, somewhat of the appearance of an amphitheatre. It stretches from near the summit down to the upper limit of the wooded region of the mountain, and has a remarkably desolate aspect, presenting a vast expanse of bare and rugged lava.
1669 Formation of Monti Rossi\nOf the numerous eruptions of Etna, one of the most memorable was that of 1669, when an immense rent about 20 km long formed on the flank of the mountain above Nicolosi, about half way between Catania and the top of the great crater, from which a vast torrent of lava descended. After flowing for several miles, and destroying a part of Catania in its course, it entered the sea. This formed a small promontory, which has since proved very useful as a breakwater. As well as this lava flow, large quantities of ashes, cinders, stones, and other material were thrown up at the same time. This formed two conical hills, more than 100 m in height above the slope of the mountain from which they rose, and measuring nearly 3 km in circumference at their base. These hills were named Monti Rossi.
Eruption of 1852 -- Whirlwinds -- Lava torrents\nAn eruption in 1852 was of great violence. It began with hollow underground rumblings, and the ascent of dense columns of vapour, mingled with dust and ashes, high into the air. These were speedily whirled into enormous eddies by fierce whirlwinds. Two new mouths were formed on the side of the mountain, and these vomited forth immense streams of lava, which rushed with the vehemence of a torrent down the steep. The violence of the commotion increasing, the two mouths were, by the crumbling of the intervening rocks, blended into one, and then huge fragments of the broken rock were hurled to a great height, along with vast quantities of hot stones, cinders, and black sand. Increasing quantities of lava were now poured from the greatly enlarged opening, and these formed on the plains below a great river of liquid fire, nearly two miles in breadth, and between seven and eight feet in depth, which advanced at the rate of upwards of a hundred feet in an hour, carrying before it devastation and ruin. Its course being through a highly cultivated country, the damage it inflicted was immense. This eruption continued for several months, with only short intervals of rest. Mount Etna was again active in 1865.
Cascades of lava\nIt has more than once happened, that the lava-streams of Etna, in\ntheir descent from the crater of eruption, have come to a\nprecipitous wall of rock, over which they have plunged in a cascade\nsimilar to that formed by the lava of Vesuvius in 1855, but on a\nless magnificent scale, as respects the height of the fall. One of\nthese occasions was during the eruption of 1771, and another during\nthat of 1819.
Description of crater
The principal cone of Mount Etna was ascended in 1834 by Messrs.\nElie de Beaumont and Leopold von Buch. The former describes what\nthey saw in the following terms:--"It was to us a moment of\nsurprise difficult to describe, when we found ourselves\nunexpectedly on the margin--not, indeed, of the great crater--but\nof an almost circular gulf, nearly three hundred feet in diameter,\nwhich does not touch the great crater save at a small part of its\ncircumference. We peered eagerly into this nearly cylindrical\nfunnel; but vain was our search into the secret of its volcanic\naction. From the almost horizontal tops of the nearly vertical\nsteeps, nothing can be descried but the upper cone. On trying to\nreckon those one below another, vision becomes gradually lost in\nthe perfect darkness beneath. No sound issues from this darkness.\nThere are only exhaled slightly sulphurous white vapours, chiefly\nsteam. The dismal aspect of this black and silent gulf, in which\nour view was lost--its dark moist sides, along which crept, in a\nlanguid and monotonous manner, long flakes of vapour of a sombre\ngray--the great crater to which this narrow gulf is attached, with\nits confused heap of diverse substances, coloured yellow, gray,\nred, like the image of chaos--all presented around us an aspect\nquite funereal and sepulchral."
Empedocles
The French geologist, in having escaped from his visit to the\ncrater with nothing worse than a fit of the vapours, came off\nbetter than Empedocles, the Sicilian philosopher, in the days of\nold: for, as the story goes, this inquisitive sage, being very\nanxious to have a peep into the crater, and venturing too near,\ntoppled in altogether, and nothing more was seen of him, except one\nof his sandals, which was vomited up by the volcano--thus conveying\nto his friends an intimation of the manner of his death.
Enceladus
Some incredulous persons allege that this story has no better\nfoundation than the fable of the poets, that the giant Enceladus,\nson of Titan and Terra, having offended Jupiter, the infuriated god\nfirst felled him with a thunderbolt, and then put Mount Etna as a\nsort of extinguisher on the top of him--his restlessness underneath\nfully accounting for all the commotions of the mountain.
Craters of 1865
Soon after the eruption which took place towards the end of January\n1865, the craters then opened were visited by M. Fouqué, a French\ngeologist. At the time of his visit, 10th March, they were seven in\nnumber, and he thus describes their modes of action:--
"The three upper craters produced two or three times a minute,\npowerful detonations like thunderclaps. The lower craters, on the\ncontrary, incessantly gave forth a succession of reports too rapid\nto be reckoned. These sounds, although unremitting, were clear and\ndistinct, the one from the other. I can find no better comparison\nfor them than the strokes of a hammer falling on an anvil. Had the\nancients heard a similar noise, I can readily conceive whence arose\nthe idea of their imagining a forge in the centre of Etna, with the\nCyclops for workmen."
Etna, Mount
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