« ПредыдущаяПродолжить »
the studied at length in an eruption. The day. The next eruption occurred in elder Pliny, who commanded the Roman 1306; between which era and 161, there fint was then stationed at Misenum; was only one other (in 1500, and that a and, in his anxiety to obtain a near view slight one. During this interval, a memo'the phenomena, he lost his life, being orable event occurred in the Phlegræan rutorated with sulphureo:is vapors. His fields—the sudden formation of a new pupbew, the young4T Pimy, remained at mountain in 1538. Frequent earthquakes Menurn, and has given us, in his Lets for two years preceding disturbed the ters, a lively description of the awful neighborhood of Pozzuoli ; but it was not Brene. A degree column of vapor was until the twenty-seventh and twentyfir-e * rising vertically from Vesuvius, eighth of September, 1938, that they beand then spreading itself out laterally, só caine alarming, when rot less than twenWat its upper portion resembled the ty shocks were experienced in twenty-four head, and its lower, the trunk of the hours. At length, on the night of the pipe, which characterizes the Italian (wenty-ninth, two hours after sunset, a landscape. This black cloud was pierced, gulf opened between the little town of prasionally, by flashes of fire as vivid as Tripergola, which once existed on the lightning, succeeded by darkness more site of the Monte Nuovo, and the baths in profound than night. Ashes fell even its suburbs, which were much frequented. upon the ships at Misenum, and caused a A large fissure approached the town with shoal in one part of the sea. The ground a tremendous noise, and began to dis. rocked, and the sea receded from the charge pumice-stopes, blocks of unmelted shores, so that many marine animals lava, and ashes mixed with water, and, were seen on the dry sand. The appear- occasionally, flames. The ashes fell in ances above described agree perfectly immense quantities, even at Naples. The with those witnessed in more recent erup- sea retired suddenly for two hundred tions, especially those of Monte Nuovo, yards, and a portion of its bed was left dry; in 1538, and of Vesuvius, in 1822. In and the whole coast from Monte Nuovo all times and countries, indeed, there is a to beyond Pozzuoli was upraised to the striking uniformity in the volcanic phe- height of many feet above the bed of the nomena ; but it is most singular ihat Mediterranean, and has ever since rePliny, although giving a circumstantial mained permanently elevated. On the detail of so many physical facts, and en- third of October, the eruption ceased, so larging upon the manner of his uncle's that the hill Monte Nuovo, which is 440 death, and the ashes which fell when he feet above the level of the bay, and a mile was at Stabiæ, makes no bllusion what- and a half in circumference at its base, ever to the sudden overwhelming of two and which was chiefly thrown up in a large and populous cities, Herculaneum day and a night, was accessible. The and Pompeii. (q. v.) Tacitus, the friend depth of its crater is 421 feet from the and contemporary of Pliny, when ad- summit of the hill, so that its bottom is verring, in general terms, to the convul- only nineteen feet above the level of the sion, says merely, that “cities were swal- sea. For nearly a century after the birth lowed up or buried" (haustæ aut obrute of Monte Nuovo, Vesuvius still continuurbes. Hist. lib. i.). Ii does not appear ed in a state of tranquillity. Bracini, who that, in the year 79, any lava flowed from visited Vesuvius not long before the erupVesuvius: the ejecied substances appear tion of 1631, gives the following descripto have consisted entirely of sand and tion of its interior. The crater was five fragments of older lava. In 10:36, the miles in circumference, and about one first eruption of flowing lava occurred. thousand paces deep. Its sides were covA second happened in 1019, and a third ered with brush wood, and at the bottom in 11:30; after which a great pause en- there was a plain on which cattle grazed. sued of 168 years. During part of 1301, In the woody parts, wild boars frequently earthquakes had succeeded one another harbored. But at length these forests with tearful rapidity; and they terminated and grassy plains were suddenly conat last with the discharge of a lava sumed-blown into the air, and their stream from a point named the Campo del ashes scattered to the winds. In DecemArso, not far from the town of Ischia. ber, 1631, seven streams of lava poured This lava ran quite down to the sea-a at once from the crater, and overflowed distance of about two miles. Its surface several villages on the sides and at the is of a reddish-black color; and it is foot of the mountain. Great floods of almost as sterile, after a period of five mud were as destructive as the lava itcenturies, as if it had cooled down yester- self; for such (as often happens during these catastrophes) was the violence of mense volumes of aqueous vapor are the rains produced by the evolution of evolved from a crater during eruptions, aqueous vapor, that torrents of water de- and often for a long time subsequently to scended the cone, and, becoming charged the discharge of scoriæ and lava. These with impalpable volcanic dust, rolled vapors are condensed in the cold atmosalong loose ashes, acquiring such consist- phere surrounding the high volcanic ency as to deserve the appellation of peak; and heavy rains are caused someaqueous lava. A brief period of repose times even in countries where, under ensued, which lasted only until the year other circumstances, such a phenomenon 1666, from which time to the present, is entirely unknown. The floods thus there bas been a constant series of erup- occasioned sweep along impalpable dust tions, with rarely an interval of rest ex- and light scoriæ, till a current of mud is ceeding ten years. The modern lavas produced, which is often more dreaded of Vesuvius are characterized by a large ihan an igneous stream, from the greater proportion of augite. When they are velocity with which it moves. After composed of this mineral and feldspar, Vesuvius, the most authentic records rethey differ in composition but slightly late to Ætna, which rises, near the sea, in from many of the trap-rocks. (See Trap:) solitary grandeur, to the height of nearly They are often porphyritic, containing 15,000 feet, the mass consisting chiefly of disseminated crystals of augite, leucite, or volcanic matter ejected above the surface some other mineral, imbedded in a more of the water. The base of the cone is earthy base. These porphyritic lavas are eighty-seven miles. Ætna appears to often extremely compact. In the lava have been in activity from the earliest currents of central France (those of Vive- times of tradition. Thucydides informs rais), the uppermost portion, often forty us that between the colonization of Sicily feet or more in thickness, is an amor- by the Greeks and the commencement of phous mass passing downwards into lava, the Peloponnesian war (B. C. 431), three irregularly prismatic; and under this eruptions had occurred. A great eruption there is a foundation of regular and ver- occurred in the year 1669. The lava, after tical columns, in that part of the current having overflowed fourteen towns and vilwhich must have cooled most slowly. lages, some having a population of between A great variety of minerals are found in 3000 and 4000 inhabitants, arrived, at the lavas of Vesuvius and Somma. Au- length, at the walls of Catania. These had gite, leucite, feldspar, mica, olivine, spec- been purposely raised to protect the city; ular iron, idocrase, garnet and sulphur but the burning flood accumulated tillit are most abundant. It is an extraordi- rose to the top of the rampart, which was nary fact, that, in an area of three square sixty feet in beight, and then fell in a miles round Vesuvius, a greater number fiery cascade, and overwhelmed part of of mineral species have been found than the city. The wall, however, was not in any spot, of the same dimensions, on thrown down, but was discovered long the surface of the globe. Many of these afterwards by excavations made in the are peculiar to this locality. A small rock by the prince of Biscari; so that part of the ejected matter, however, re- the traveller may now see the solid lava mains so bear to the volcanic orifice. A curling over the top of the rampart, as if large portion of sand and scoriæ is borne still in the very act of falling. This great by the winds and scattered over the sur- current had performed a course of fifteen rounding plains, or falls into the sea ; and miles, before it entered the sea, where it much more is swept down by torrents was still 600 yards broad and 40 feet deep. into the deep during the intervals, often A gentleman of Catania, named Pappaprotracted for many centuries, between lardo, desiring to secure the city from the eruptions. These horizontal deposits of approach of the threatening torrent, went tufaceous matter become intermixed with out with a party of fifty men, whom he sediment of other kinds,and with shells and had dressed in skins to protect them from corals, and, when afterwards raised, form the heat, and armed with iron crows and rocks of a mixed character, such as tufas, hooks. They broke open one of the solid peperinos and volcanic conglomerates. walls which flanked the current near Besides the ejections which fall on the Belpasso, and immediately forth issued a cone, and that much greater mass which rivulet of melted matter, which took the finds its way gradually to the neighboring direction of Paternd; but the inhabitants sea, there is a third portion, often of no in- of that town, being alarmed for their considerable thickness, composed of allu- safety, took up arms, and put a stop to vions, spread over the valleys and plains, at further operations. In 1811, the great small distances from the volcano. Im- crater testified, by its violent detonations, that the lava had ascended to near the about equal in activity to the burning summit of the mountain, by its central mountains in other districts, we may then duct. A violent shock was then felt, and compute that there happen on the earth a stream broke out from the side of the about 2000 eruptions in the course of a cone, at no great distance from its apex. century, or about twenty every year, or Shortly after, other streams, to the num- one in eighteen days. However inconber of six, broke out in succession, still siderable, therefore, may be the superficial lower down the mountain, but all in the rocks, which the operations of fire prosame straight line. In 1819, three large duce on the surface, we must suppose mouths opened very near those which the subterranean changes now constantly were formed in the eruptions of 1811, in progress to be on the grandest scale. from which flames, red-hot cinders and The loftiest volcanic cones must be insigsand were thrown up, with loud explo- nificant when contrasted with the products sions. A few minutes afterwards, anoiher of fire in the nether regions. One of the mouth opened below, from which flames earliest hypotheses to account for volcanic and smoke issued; and finally, a fifth, eruptions is that which attributes them to lower still, whence a torrent of lava the eructations of a perpetual central fire, flowed, which spread itself, with great to which, however, the nature of the lava, velocity, over the valley Del Bove. This the method of its projection, and, above stream flowed two miles in the first twen- all, the known laws of the communication ty-four hours, and nearly as far in the of heat, are msurmountably opposed. The succeeding day and night. As the last sudden evolution of steam has also freexample of modern volcanic eruptions, quently been resorted to. They have also we shall mention that of Jorullo, in Mex- been referred to the ignition of beds of ico, in 1759. The plain, which was the coal; and Werner supposed that the fire site of the eruption, is thirty-six leagues thus produced fused the circumjacent from the sea, and, at the time of the rocks, and formed lava. Others have calleruption, was occupied by fertile fields of ed sulphur, pyrites, petroleum and bitusugar-cane and indigo.' In the month men to their aid, but have sought in vain of June, hollow sounds, of an alarming for the necessary supply of oxygen, withnature, were heard, and earthquakes suc- out which these combustibles could not ceeded each other for two months, until
, perform their required part; and, indeed, in September, flames issued from the if we grant an unlimited supply of that ground, and fragments of burning rocks element, the projectile force—the vaporwere thrown to prodigious heights. Six still remains to be accounted for. Others volcanic cones, composed of scoriæ and have imagined a great depôt of electric fragmentary lava were formed on the line matter, pent up in certain submarine and of a chasm which ran in the direction subterranean caverns, and occasionally from north-north-east to south-south-west. sallying forth to fuse and blow up the The least of these cones was 300 feet in surrounding materials. The most plauheight; and Jorullo, the central one, was sible theory of volcanoes is that suggested elevated 1600 feet above the level of the by sir H. Davy, soon after he had dissea. A subsequent eruption of Jorullo covered the nature of the earthy and happened in 1819, accompanied by an alkaline bodies. Indeed, it enables us, in earthquake. The city of Guanaxuato, most cases, upon just principles of sound distant about 140 miles from Jorullo, was analogy, to explain their origin ; for lava covered with ashes, to the depth of six consists of earthy and alkaline bodies, inches, from this eruption. During the ejected in intense ignition; and it is assolast century, about fitty eruptions are re- ciated with vapor, with explosions of hycorded of the five European volcanoes, drogen gas, with the production of nitroVesuvius, Ætna, Volcano, Santorin and gen; and, in short, there is every concomIceland; but many beneath the sea, in the itant circunstance to lead to the concluGrecian Archipelago, and near Iceland, sion, that there exist, in the bowels of the may, doubtless, have passed unnoticed. earth, masses of those highly inflammable If some of them produced no lava, others, metallic bodies, constituting the bases of on the contrary, like that of Skoptar Jo. the earths and alkalies; and these and kul, in 1783, poured out melted matter water are essential requisites for the profor five or six years consecutively. Now, duction of the phenomena that precede, if we consider the active volcanoes of accompany and follow the eruption of Europe to constitute about a fortieth part volcanoes: they may be referred to, as of those already known on the globe, and accounting for the earthquakes, the excalculate that, one with another, they are plosions and the gaseous products; and they are the only agents, with which we appeared with advantage as a public are acquainted, capable of fulfilling all speaker. In 1791, he published his dethe requisites. How or where these istical work, entitled Les Ruines, ou Mébodies exist, at what depths, in what ditations sur les Révolutions des Empires. quantity, and how accessible to water, are After the conclusion of the sessions of questions that we cannot solve; but it the national assembly, he accompanied is a curious fact, that water is always M. Pozzo di Borgo to Corsica, where he found connected with volcanoes. Vesu- had projected some agricultural improvevius, Ætna and Hecla are upon the verge ments. He made attempts to establish of the sea; and in the vicinity of the burn- in that island the cultivation of the sugaring mountains of the Cordilleras there are cane, indigo, and other tropical plants; lakes; and it has been observed, that but he was unsuccessful. Returning to springs and lakes suddenly dry up pre- Paris, he suffered persecution under the vious to the active eruption of a volcano. reign of terror; and, after ten months' imVOLGA. (See Wolga.)
prisonment, the fall of Robespierre reVOLAYNIA ; a government of the Rus- stored him to liberty. In November, sian empire, between the governments 17,94, he was appointed professor of hisof Grodno and Podolia; square miles, tory at the normal school; and the course 29,300; population, about 1,500,000. While of lectures on the philosophy of history Poland was independent, Volhynia form- which he delivered, and which was pubed a province of that kingdom, which lished and translated into English, added bordered with the Ukraine on the south- considerably to his reputation. In 1795, east. The soil is fertile, producing wheat he made a voyage to the U: States of and rye, and its pasture lands are exten- America; and he would probably have sive ; but a great part of the surface is settled in America, had not the prospect forest. From its frontier situation, it has of a war with France induced him to often been exposed to the evils of invasion. return home in the spring of 1798. After Since 1793, it has been in the possession the revolution which elevated Bonaparte of Russia. Volhynia was in insurrection to the consulship, he was nominated a in 1831, but shared the fate of Poland, senator; and it is said the office of second when that unfortunate country was again consul was designed for him, but his potrampled under foot by the victorious litical opinions prevented the appointbarbarians. (See Poland, and Russia.) ment from taking place. In the senate, Volition. (See Will.)
he coöperated with Lanjuinais, Cabanis, Volney, Constantine Francis Chasse- Destutt de Tracy, Collaud, Garat, and beuf, count de, peer of France, a cele- others, whose influence was constantly brated French writer, was born at Craon, exerted in the cause of freedom. After in Brittany, in 1755. Inspired, at an the restoration, Volney, by a decree of the early age, with a desire to visit foreign fourth of June, 1814, was designated a countries in search of knowledge, he no member of the chamber of peers, where sooner became master of a small patri- he remained faithful to his principles, monial estate, than he converted it into always appearing among the ardent demoney, and embarked for the Levant, fenders of the rights of the nation. His travelled through several parts of Egypt death took place at Paris, in 1820. • Beand Syria, and, after a residence for some sides the works already mentioned, he time in a Maronite convent on mount published Simplificalion des Langues Libanus, for the purpose of studying the Orientales, ou liéthode, nouvelle et facile Oriental languages, returned to France, d'apprendre les Langues Arabe, Persane whence he had been absent more than et Turque, avec les Caractères Européens two years. The fruits of his inquiries (1795, 8vo.); Tableau du Climat et du Sol appeared in his Voyage en Syrie et en des États Unis d'Amérique (1803, 2 vols., Egypte (2 vols., 8vo.), which was trans- 8vo.), with a Vocabulary of the Language lated into English, Dutch and German. of the Miamis; Chronologie d'Herodote This work procured him much reputa- conformé à son Terte (1808, 2 vols., 8vo.); tion; and, taking up his residence at Recherches nouvelles sur l'Histoire AnAuteuil, near Paris, he became intimately cienne (1814–1815, 3 vols., 8vo.). His connected with some of the most eminent Cuvres complètes, with his Life, appeared among his literary contemporaries. On at Paris, in 1821, in 8 vols. the convocation of the states-general, in VOLPATO, Giovanni, an engraver, born at 1789, Volney was elected a deputy from Bassano, in 1733, spent his early years in exthe tiers etat of Anjou, when he em- ecuting drawings for embroidery. Having braced the cause of liberty, and frequently acquired the use of the burin, without any
instruction, he afterwards went to Venice, state, they were conquered, and disappearwhere he executed engravings, in con- ed from history, like the other tribes of nexion with Bartolozzi, for Wagner, a Latiuin. picture dealer, and finally left Venice for Volta, Alessandro, descended from a Rome. Here a society of amateurs, at respectable family of Como, was born in the head of whom was Ercole Bonajuti, that place, in 1745, and died there in had been formed for the purpose of pro- 1827. While pursuing his studies at Cocuring engravings of Raphael's works in mo, be displayed not less inclination for the Vatican. The drawings of the the poetic art than for the severe sciences, Spanish painter La Veja, in eighty sheets, and composed a fine Latin poem upon which had been prepared by a labor of physics. But he soon after devoted himthree years for cardinal Silvio Valenti, self entirely to physical inquiries, and and which had been bequeathed by the laid the foundation of his fame in two cardinal Luigi Valenti to the Vatican li- treatises, published in 1769 and 1771, in brary, were made the basis of this work. which he gave a description of a new Volpato was employed in its execution, electrical machine. In 1774, Volta beand soon became distinguished among came rector of the gymnasium in Como, the artists connected with him. The six and professor of physics, and, in 1779, sheets executed by him are of the high- was transferred to Pavia. Here he oce est merit. They reproduce, as far as is pose cupied himself entirely with electrical sible in a small space, the impression of researches. He had previously (1777) the original, and prove how fully the art. invented the electrophorus, and his inist appreciated the pictorial merits of vention of the electroscope was also an those great paintings, by his masterly important improvement. (See Electricity.) distribution of light and shade. The His observations upon the bubbles which most skilful union of the burin with the arise from stagnani water, led him also to dry-point could alone have enabled him some valuable discoveries in regard to to accomplish this difficult task in a work gases. The electrical pistol, the eudiomof such extent. The publication of Ra- eter, the lamp with inflammable air, the phael's loggie and arabesques placed Vol- electrical condenser, and other inventions, pato at the head of a school of design, are among his claims to renown. He and gave him the honor of having ren- next turned his attention to some of the dered the productions of that great mas- atmospherical phenomena, as the nature ter more generally known, and of having of hail, &c., and subsequently increased awakened a purer taste among engravers. his reputation by the discovery of the Accuracy of execution, and attention to Voltaic pile (see Galvanism), and, in 1782, the pictorial effect, so far as it depends made a tour through France, Germany, not upon coloring, but upon light and England and Holland, on which occasion shade, are the distinguishing merits of he was treated with great respect by Halhis school, from which proceeded Ra- ler, Joseph II and Voltaire.' On his rephael Morghen (q. v.), at first the pupil, turn to Italy, he introduced the cultivaafterwards the friend, and finally the son- tion of the potato into Lombardy. In in-law of Volpato. Gavin Hamilton, the 1794, he received the Copleian medal companion of his Socratic suppers, at from the royal society of London, on acwhich Canova also used to be present, count of his paper upon the condenser ; was not without influence upon the taste and, in 1801, bis electric apparatus atof the artist. Volpato died in 180:3, and tracted so much notice in France that the Canova honored the memory of his first consul made him a present of 6000 friend and benefactor by a relief, which francs. He was subsequently deputy is placed in the hall of the church of the from the university of Pavia to the conApostles in Rome.
sulta held at Lyons, and Napoleon conVolsci; an Ausonian tribe, which re- ferred upon him the cross of the legion sided, before the foundation of Rome, in the of honor, and the order of the iron ancient Latium (now Campagna di Roma). crown. In 1815, the emperor Francis apThey had a republican government. Livy pointed him director of the philosophical calls them the eternal enemies of Rome. faculty in the university of Pavia. As a Their principal city was Antium, the ru- man, Volta was simple, modest and reliins of which are to be seen in the neigh- gious, a good father and citizen. Antinoborhood of rape Angio. Corioli, from ri edited a collection of his works (Opere which Coriolanus derived his surname, di Volta, Florence, 1816, 5 vols.), and prowas another city of theirs. After having fessor Zuccala published a eulogy upon several times endangered the Roman him (Elogio di l'olta) in 1827.