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VESUVIUS (also Vesevus in ancient poets)
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See also:VESUVIUS (also Vesevus in See also:ancient poets) , a See also:volcano rising from the eastern margin of the See also:Bay of See also:Naples in See also:Italy, about 7 M. E.S.E. of Naples, in the midst of a region which has been densely populated by a civilized community for more than twenty-five centuries. Hence the See also:mountain has served as a type for the See also:general popular conception of a volcano, and its See also:history has supplied a large See also:part of the See also:information on which See also:geological theories of volcanic See also:action have been based. The height of the mountain varies from See also:time to time within limits of several See also:hundred feet, according to the effects of successive eruptions, but averages about 4000 ft. above See also:sea-level (in See also:June 1900, 4275 ft., but after the eruption of rgo6 considerably less). Vesuvius consists of two distinct portions. On the See also:north-ern See also:side a lofty semicircular cliff, reaching a height of 3714 ft., See also:half encircles the See also:present active See also:cone, and descends in See also:long slopes towards the plains below. This precipice, known as See also:Monte Somma, forms the See also:wall of an ancient prehistoric See also:crater of vastly greater See also:size than that of the present volcano. The continuation of the same wall See also:round its See also:southern half has been in See also:great measure obliterated by the operations of the See also:modern vent, which has built a younger cone upon it, and is gradually filling up the hollow of the prehistoric crater. At the time of its greatest dimensions the volcano was perhaps twice as high as it is now. By a See also:colossal eruption, of which no See also:historical See also:record remains, the upper half of the cone was blown away. It was around this truncated cone that the See also:early See also:Greek settlers founded their little colonies. At the beginning of the See also:Christian era, and for many previous centuries, no eruption had been known to take See also:place from the mountain, and the volcanic nature of the locality was perhaps not even suspected by the inhabitants who planted their See also:vine-yards along its fertile slopes, and built their numerous villages and towns around its See also:base. The geographer See also:Strabo, however, detected the probable volcanic origin of the cone and See also:drew See also:attention to its cindery and evidently See also:fire-eaten rocks. From his See also:account and other references in classical authors we gather that in the first See also:century of the Christian era, and probably for hundreds of years before that time, the sides of the mountain were richly cultivated, as they are still, the vineyards being of extraordinary fertility. The See also:wine they produce is known as Lacrimae Christi. But towards the See also:top the upward growth of vegetation had not concealed the loose ashes which still remained as See also:evidence of the volcanic nature of the place. On this barren See also:summit See also:lay a wide See also:flat depression, surrounded with rugged walls of See also:rock, which were festooned with See also:wild vines. The present crater-wall of Monte Somma is doubtless a relic of that time. It was in this lofty rock-girt hollow that the gladiator See also:Spartacus was besieged by the See also:praetor See also:Claudius Pulcher; he escaped by twisting See also:ropes of vine branches and descending through unguarded fissures in the crater-rim. A See also:painting found in See also:Pompeii in 1879 represents Vesuvius before the eruption (Notizie degli scavi, 188o, pl. vii.). After centuries of quiescence the volcanic See also:energy began again to See also:manifest itself in a See also:succession of earthquakes, which spread alarm through See also:Campania. For some sixteen years after 63 these See also:convulsions continued, doing much damage to the surrounding towns. At Pompeii, for example, among other devastation, the See also:temple of See also:Isis was shaken into ruins, and, as an inscription records, it was rebuilt from the See also:foundations by the munificence of a private See also:citizen. On the 24th of See also:August 79 the earthquakes, which had been growing more violent, culminated in a tremendous See also:explosion of Vesuvius. A contemporary account of this event has been preserved in two letters of the younger See also:Pliny to the historian See also:Tacitus. He was staying at See also:Misenum with his See also:uncle, the See also:elder Pliny, who was in command of the See also:fleet. The latter set out on the afternoon of the 24th to See also:attempt to See also:rescue See also:people at See also:Herculaneum, but came too See also:late, and went to See also:Stabiae, where he spent the See also:night, and died the following See also:morning, suffocated by the poisonous fumes which were ex-haled from the See also:earth. This eruption was attended with great destruction of See also:life and See also:property. Three towns are known to have been destroyed—Herculaneum at the western base of the volcano, Pompeii on the See also:south-See also:east side, and Stabiae, still farther south, on the site of the modern Castellamare. There is no evidence that any See also:lava was emitted during this eruption. But the abundant See also:steam given off by the volcano seems to have condensed into copious See also:rain, which, mixing with the See also:light volcanic dust and ash, gave rise to torrents of pasty mud, that flowed down the slopes and overwhelmed houses and villages. Herculaneum is believed to have been destroyed by these " See also:water lavas," and there is See also:reason to suppose that similar materials filled the cellars and See also:lower parts of Pompeii. Comparing the statements of Pliny with the facts still observable in the See also:district, we perceive that this first recorded eruption of Vesuvius belongs to that phase of volcanic action known as the paroxysmal, when, after a longer or shorter See also:period of See also:comparative tranquillity, a volcano rapidly resumes its energy and the partially filled-up crater is cleared out by a succession of tremendous explosions. For nearly fifteen hundred years after the See also:catastrophe of 79 Vesuvius remained in a See also:condition of less activity. Occasional eruptions are mentioned, e.g. in A.D. 203, 472 and 685, and nine in the See also:middle ages down to 1500. None, however, was of equal importance with the first, and their details are given vaguely by the authors who allude to them. By the end of the 15th century the mountain had resumed much the same general aspect as it presented before the eruption described by Pliny. Its crater-walls, some 5 M. in circumference, were hung with trees and brushwood, and at their base stretched a wide grassy See also:plain, where See also:cattle grazed and the wild See also:boar lurked in the thickets. The central See also:tract was a lower plain, covered with loose ashes and marked by a few pools of hot and saline water. At length, after a See also:series of earthquakes lasting for six months and gradually increasing in violence, the volcano burst into renewed paroxysmal activity on the 16th of See also:December 1631. Vastclouds of dust and stones, blown out of the crater and See also:funnel of the volcano, were hurled into the See also:air and carried for hundreds of See also:miles, the finer particles falling to the earth even in the Adriatic and at See also:Constantinople. The clouds of steam condensed into copious torrents, which, mingling with the See also:fine ashes, produced muddy streams that swept far and wide over the plains, reaching even to the See also:foot of the See also:Apennines. Issuing from the flanks of the mountain, several streams of lava flowed down towards the See also:west and south, and reached the sea at twelve or thirteen different points. Though the inhabitants had been warned by the earlier convulsions of the mountain, so swiftly did destruction come upon them that 18,000 are said to have lost their lives. Since this great convulsion, which emptied the crater, Vesuvius has never again relapsed into a condition of See also:total quiescence. At intervals, varying from a few See also:weeks or months to a few years, it has broken out into eruption, sometimes emitting only steam, dust and scoriae, but frequently also streams of lava. The years 1766-67, 1779, 1794, 1822, 1872 and 1906 were marked by See also:special activity. The last completely altered the aspect of the cone, considerably reducing its height.
The modern cone of the mountain has been built up by successive discharges of lava and fragmentary materials round a vent of eruption, which lies a little south of the centre of the prehistoric crater. The southern segment of the ancient cone, answering to the semicircular wall of Somma on the north side, has been almost concealed, but is still traceable among the younger accumulations. The numerous deep ravines which indented the sides of the prehistoric volcano, and still See also:form a marked feature on the See also:outer slopes of Somma, have on the south side served as channels to See also:guide the currents of lava from the younger cone. But they are gradually being filled up there and will ultimately disappear under the sheets of -molten rock that from time to time See also:rush into them from above. On one of the ridges between these radiating valleys an See also:observatory for watching the progress of the volcano was established by the Neapolitan, See also:government, and is still supported as a See also:national institution. A' continuous record of each phase in the volcanic changes has been taken, and some progress has been made in the study of the phenomena of Vesuvius; and in prognosticating the occurrence and probable intensity of eruptions. The foot of the See also:tone is reached from Naples by electric railway, and thence a See also:wire-rope railway (opened in 188o) carries visitors to within 150 yds. of the mouth of the crater.
See See also: Journ. Geol. See also:Soc. vol. xl. p. 85; J. L. Lobley, See also:Mount Vesuvius (See also:London, 1889) ; F. Furchheim, Bibliografia del Vesuvio (Naples, 1897); T: McK. See also:Hughes, " Herculaneum,' in Proc. Camb. See also:Anti z. Soc. No. xlviii. p. 25 (See also:Cambridge, 1908). (A. GE.; T. Additional information and CommentsThere are no comments yet for this article.
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