Page:Encyclopædia Britannica, Ninth Edition, v. 8.djvu/655

Rh ETNA 631 emitted lava. A year later, in May 1537, a fresh outburst occurred. A number of new mouths were opened on the south slope of the mountain near La Fontanelle, and a quantity of lava was emitted, which flowed in the direction of Catania, destroying a part of Nicolosi, and St Antonio. In four days the lava had run fifteen miles. The cone of the great crater suddenly fell in, so as to become level with the Piano del Lago. The height of the mountain was thus diminished l&amp;gt;y 320 feet. Three new craters opened in November 1566, on the north-east slope of the mountain. In 1579, 1603, 1607, 1610, 1614, and 1619, unimportant eruptions occurred. In February 1633 Nicolosi was partially destroyed by a violent earthquake, and in the following December earthquakes became frequent around the mountain. In 1646 a new mouth opened on the north-east side, and live years later several new mouths opened on the west side of die mountain, and poured out vast volumes of lava, which threatened to overwhelm Bronte. We have a more detailed account of the eruption of 1669 than of any previous eruption. It was observed by many men of different nations, and we find accounts of it in the Philosophical Transactions, and in several separate narra tives in French and Italian. Perhaps the most accurate and com plete description is that given by Alfonso Borelli, professor of mathematics in Catania. The eruption was in every respect one of the most terrible on record. On the 8th of March the sun was obscured, and a whirlwind blew over the face of the mountain ; at the same time earthquakes were felt, and they continued to increase in violence for three days, at the end of which Nicolosi was con verted into a heap of ruins. On the morning of the llth a fissure nearly 12 miles in length opened in the side of the mountain, and t .xtended from the Piano di St Leo to Monte Fruinento, a mile from the summit. The fissure was only six feet wide, but it seemed to be of unknown depth, and a bright light proceeded from it. Six mouths opened in a line with the principal fissure, and emitted vast volumes of smoke, accompanied by low bellowing, which could be heard 40 miles off. Towards the close of the day a crater opened about a mile below the others, and ejected red-hot stones to a considerab.e distance, and afterwards sand and ashes, which covered the country for a distance of 60 miles. The new crater soon vomited forth a torrent of lava, which presented a front of 2 miles. It encircled Monpilieri, and afterwards flowed towards Belpasso, a town of 8000 inhabitants, which was speedily destroyed. Seven mouths of fire opened around the new crater, and in three days united with it, forming one large crater 800 feet in diameter. The torrent of lava had continued to flow, and it destroyed the town of Mascahu ia on the 23rd of March. On the same day the crater cast up great quantities of sand, ashes, and siorire, and formed above itself the great double coned hill called Monti Rossi, from the red colour of the ashes of which it is mainly composed. On the 25th very violent earthquakes occurred, and the cone of the great central crater was shaken down into the crater, for the fifth time since the first century A.D. The original current of lava had divided into three streams, one of which destroyed San Pietro, the second Camporotondo, and the third the lands about Mascalucia, and afterwards the village of Misterbianco. Fourteen villages were afterwards destroyed, and the lava made its way towards Catania. At Albanello, two miles from the city, it undermined a hill covered with corn fields, and carried it forward a considerable distance ; a vineyard was also seen to be floating on its fiery surface. When the lava reached the walls of Catania it accumulated without pro gression, until it rose to the top of the wall, 60 feet in height, and it then fell over in a fiery cascade, and overwhelmed a part of the city. Another portion of the same stream threw down 120 feet of the wall, and flowed through the city. On the 23rd of April the lava reached the sea, which it entered as a stream 600 yards broad and 40 feet deep. The stream had moved at the rate of 13 miles in twenty days, but as it cooled it moved less quickly, and during the last 23 days of its course it only moved two miles. On reach ing the sea the water of course began to boil violently, and clouds of steam arose, carrying with them particles of scoriae. The volume of lava emitted during this eruption amounted to many millions of cubic feet. Ferrara considers that the length of the stream was at least 15 miles, while its average width was between 2 and 3 miles, so that it covered at least 40 square miles of surface. For a few years after this terrible eruption Etna was quiescent, but in 1682 a new mouth opened on the east side of the mountain, and lava issued from it and rushed down the precipices of the Yal del Hue. In 16S8 a torrent of lava burst from an opening in the great the Val del Bue. Early in January 1693 clouds of black smoke were poured from the great crater, and loud noises, resembling the dis charge of artillery, were heard. A violent earthquake succeeded, and Catania was shaken to the ground, burying 18,000 of its inhabitants. It is said that in all fifty cities and towns were destroyed in Sicily, together with from 60~000 to 100,000 inhabitants. Lava was emitted from the crater, the cone of which was lowered by the eruption. In the following year Etna again entered into eruption. In March 1702 three mouths opened in the Contrada del Tri- foglietto, near the head of the Yal del Bue. In 1723, 1732, 1735, 1744, and 1747 slight eruptions occurred. Early in the year 1755 Etna began to show signs of disturbance ; a great column of black smoke issued from the crater, from which forked lightning was frequently emitted. Loud detonations were heard, and two streams of lava issued from the crater. A new mouth opened near Rocca di Musarra in the Val del Bue, four miles from the summit, and a quantity of lava was ejected from it. An extraordinary Hood of water descended from the Val del Bue, carrying all before it, and strewing its path with large blocks. Recopero estimated the volume of water at 16,000,000 cubic feet, probably a greater amount than could be furnished by the sudden melting of all the winter s snow on the mountain. It formed a channel 2 miles broad, and in some places thirty-four feet deep, and it flowed at the rate of a mile in a minute and a half during the first twelve miles of its course. Lyell con siders that the flood was probably produced by the melting not only of the winter s snow, but also of older layers of ice, which were suddenly liquefied by the permeation of hot steam and lava, and which had been previously preserved from melting by a deposit of sand and ashes, as in the case of the ancient glacier found near the summit of the mountain in 1828. In November 1758, a smart shock of earthquake caused the cone of the great crater to fall in, but no eruption occurred at the time. In 1759, 1763, 1766, and 1780 eruptions occurred, and on the 18th of May in 1780 a fissure opened on the south-west side of the mountain, and extended from the base of the great crater for seven miles, terminating in a new mouth, from which a stream of lava emanated. This encountered the cone of Palmintelli in its course, and separated into two branches, each of which was about 4000 feet wide. Other mouths opened later in the year, and emitted larger quantities of lava, while in 1781 and 1787 there were slight eruptions. Five years afterwards a fresh outburst occurred ; earthquakes were prevalent, and vast volumes of smoke were carried out to sea, seeming to form a gigantic bridge between Sicily and Africa. A torrent of lava flowed towards Aderno, and a second flowed into the Val del Bue as far as Zuccolaro. A pit called La Cistcrna, forty feet in diameter, opened in the Piano del Lago near the great cone, and ejected smoke and masses of old lava saturated with water. Several mouths opened below the crater, and the country round about ZalTarana was desolated. In 1797, 1798, 1799, 1800, 1802, 1805, and 1808 slight eruptions occurred. In March 1809 no less than twenty-one months of fire opened between the summit of the mountain and Castiglione, and two years afterwards more than thirty mouths opened in a line running eastwards from the summit for five miles. They ejected jets of tire, accompanied by much smoke. In 1819 five new mouths of fire opened near the scene of the eruption of 1811 ; three of these united into one large crater, and poured forth a quantity of lava into the Val del Bue. The lava flowed until it reached a nearly perpendicular precipice at the head of the valley of Calanna, over which it fell in a cascade, and being hardened by its descent, it was forced against the sides of the tut aceous rock at the bottom, so as to produce an extraor dinary amount of abrasion, accompanied by clouds of dust, worn off by the friction. Mr Scrope observed that the lava flowed at the rate of about a yard an hour nine months after its emission. Eruptions occurred in 1831, 1832, 1833, and 1842. Near the end of the following year, fifteen mouths of fire opened near the crater of 1832, at a height of 7000 feet above the sea. They began by discharging scoriae and sand, and afterwards lava, which divided into three streams, the two outer of which soon came to a stand still, while the central stream continued to flow at the rapid rate of 180 feet a minute, the descent being an angle of 25. The heat at a distance of 120 feet from the current was 90 F. A new crater opened just above Bronte, and discharged lava which threatened the town, but it fortunately encountered Monte Vittoria, and was diverted into another course. While a number of the inhabi tants of Bronte were watching the progress of the lava, the front of the stream was suddenly blown out as by an explosion of gunpowder. In an instant red hot masses were hurled in every direction, and a cloud of vapour enveloped everything. Thirty-six persons were killed on the spot, and twenty survived but a few hours. The great crater showed signs of disturbance, by emitting dense volumes of smoke, and loud bellowings, also quantities of volcanic dust saturated with hydrochloric acid, which destroyed the vegetation wherever it fell. A very violent eruption, which lasted more than nine months, commenced on the 26th of August 1852. It was first witnessed by a party of six English tourists, who were ascending the mountain from Nicolosi in order to witnesss the sunrise from the summit. As they approached the Casa Inglesi, the crater commenced to give forth ashes and flames of fire. In a narrow defile they were met by a violent hurricane, which over threw both the mules and the riders, and urged them toward the precipices of Val del Bue. They sheltered themselves beneath some masses of lava, when suddenly an earthquake shook the moun tain, and the mules in terror iled away. They returned on foot towards daylight to Nicolosi, fortunately without having sustained injury. In the course of the night, many locchc del fnoco opened in that part of the Val del Bue called the Balzo di Trifoglietto,
 * one, and in the following year lava was emitted from a mouth in