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In addition to the above, Mount Erebus, on the south polar continent, is an active volcano of immense size. The mass and elevation of volcanoes seem to regulate the occurrence of eruptions, the smallest being the most active. Thus Stromboli, an inferior elevation, is almost always flaring as the great lighthouse of nature in the Mediterranean. Vesuvius, far less than Etna, is the most active of the two, while some of the enormous Andean cones repose for centuries.

Of existing volcanic action, the most sublime and imposing example perhaps to be found in the world, is in the island of Hawaii, formerly called Owhyhee. The whole island seems to be an immense hollow cone, having an area of 4000 square miles, and attaining an elevation of 16,000 feet, the height of Mowna Roa. It forms a pyramidal chimney over a vast incandescent mass burning beneath it, and also under some part of the bed of the surrounding ocean, having numerous vents through which the furnace below communicates with the atmosphere above. Lord Byron and a party of officers from the Blonde frigate, with the Rev. Mr. Stewart, visited the crater of Kilauea, near the base of Mowna Roa, and witnessed a scene, says the describer, more horribly sublime than any thing he had ever imagined to exist even in the idler visions of unearthly things. Arrived at the brink of the crater, they stood looking down into a fearful gulph, fifteen hundred feet in depth, and upwards of two miles in circumference. The edge of the crater was so steep, that it seemed as if by a single leap they could plunge into the lowest abyss. Its surface had all the agitation of an ocean. Billow after billow tossed its monstrous bosom into the air, and occasionally the waves from opposite directions met with such violence as to dash the fiery spray in the concussion forty or fifty feet high. Such was the agonising struggle of the action within-the appalling sounds of the conflicting elements, muttering and sighing, groaning and blowing, that one of the party shrunk back exclaiming:-"Call it weakness, or whatever you please, but I cannot look again!" About fifty cones of various height, active chimneys of volcanic fire, were counted in the abyss. Volumes of smoke and steam were ascending from these vents, but as the evening closed, fire after fire appeared glimmering through the vapour. Some of the cones were ejecting fragments of rock; others, ashes, lava, and boiling water; streams of fire seemed to be running among the labouring craters; forming a scene which, in connexion with the roar of the elements bursting from their prison, reminded the party, as one of them expressed it, of the lake that burneth with fire and brimstone. To the bottom of the abyss it is well known that a Christian convert descended, and plunged a stick into the fiery deluge! an act of female heroism to dispel the illusion of her countrymen, who were spectators at a distance, and who fancied that Peli, the god of the Kilauea fires, would punish with instant destruction any violation of his sanctuary.

One of the most tremendous volcanic eruptions ever recorded, was that which issued from the Tomboro mountain in the island of Sumbawa, for an account of which we are indebted to Sir Stamford Raffles. It began on the 5th of April, 1815, and continued with some intermissions until the June following. The sound of the explosion was heard at Ternate on the western coast of Gilolo, a distance of seven hundred and twenty geographical miles: and in Sumatra, which is nine hundred and seventy. In some parts of the island violent whirlwinds carried up men, horses, and cattle into the air; the sea was covered with the trunks of trees which had been torn up; and the ashes from the mountain, wafted to Tara and Celebes, a distance of three hundred miles, caused a darkness in the daytime more profound than had ever been known in the darkest night. To the west

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of Sumatra the sea was coated with a mass of cinders two feet thick, and many miles in extent, and ships with difficulty forced their way through it. "We grounded," says one of Sir Stamford's correspondents, "on the bank of Bima town. The anchorage of Bima must have been altered considerably, as, where we grounded, the Ternate cruiser lay at anchor in six fathoms a few months before." The area over which the effects of the eruption extended was upwards of two thousand English miles in circumference: the surface of Sumbawa was considerably altered; acclivities were turned into valleys, and valleys into elevations; and of its unfortunate inhabitants, out of a population of twelve thousand, only twenty-six persons escaped.

The volcanic regions include those where there are active vents and extinct craters, with intervening districts often shaken by earthquakes and abounding with hot springs, the evidences of subterranean igneous action. There are three large continuous areas of this kind.

To the island at the southern extremity of America, F. Magellan gave the name of Terra del Fuego, or the land of fire, no doubt from the sensible display of igneous activity; for the assertion of Malte Brun is corroborated by the evidence of Captain Hall with reference to the existence of an active volcano at the present time. Proceeding northward along the coast which fringes the Pacific Ocean, there is scarcely one degree of latitude from 46° to 27° in which there is not an active vent. The Chilian volcanoes rise up through granitic mountains. Villarica, one of the principal, is always burning, and so lofty as to be distinguished at the distance of a hundred and fifty miles. A year never passes without some slight shocks of earthquakes in the province, and about once in a century, or oftener, tremendous convulsions shake the land from one end to the other. In Peru there is the same continual disturbance of the surface, more or less violent, though only one active volcano is at present known. Still further north, about the middle of Quito, where the Andes attain their loftiest altitude, the peaks of Tunguragua, Cotopaxi, and Antisana are in frequent play. From the sides of the former mass of mud was ejected in 1797, which dammed up rivers, occasioned new lakes, and filled up valleys a thousand feet wide to the depth of six hundred feet. In the province of Pasto, farther north, there are three volcanoes; in Papayan, three others; in Guatimala and Nicaragua, no less than twenty are in an active state. Hitherto we have followed this great volcanic chain almost due north. In Mexico, however, it turns off in a side direction, extending. on the west to the isles of Revilagido and the Californian peninsula, and embracing eastward the whole of the West Indian isles. The length of this enormous chain, from Cape Horn to New Madrid in the United States, is greater than from the pole to the equator. Its westward extent is hid from us by the waters of the Pacific; but probably it reaches across the whole of its immense bed. Cotopaxi is described by Humboldt as the most beautiful and regular of all the colossal summits of the Andes, being a perfect cone, which is covered with snow, and shines with dazzling splendour at sunset. mantle, except near the edge of the crater,


There are no rocks projecting through its icy

which is surrounded by a small circular wall. The traveller tried to reach the summit,


but failed, owing to the cone being surrounded by deep ravines, and pronounces the ascent to the crater impossible. This is the highest of the Andean volcanoes which have recently been in an active state. If the 3932 feet of Vesuvius were planted upon the top of Etna, which has an elevation of 10,873, Cotopaxi would not be equalled in altitude by 4073 feet. Its eruptions have been upon a scale corresponding with its magnitude. In 1738 its fires ascended 2953 feet above the crater, and in 1744 its voice was heard at Honda, on the river Magdalena, a distance of nearly seven hundred miles. In 1768 the inhabitants of two neighbouring towns were obliged to use lanterns by day in the streets, owing to the quantity of ashes ejected, and at two hundred miles' distance Humboldt and Bonpland heard its noises day and night, like the discharges of a battery, during the explosion of 1803.

A second line of volcanic action, upon as gigantic a scale as the preceding, commences at one of the most western points of North America, the peninsula of Alaska, in latitude 55°. It pursues a western course for about two hundred geographical miles, embracing the Aleutian isles, and reaching to the opposite coast of Kamtschatka. Throughout the whole of this tract earthquakes are of frequent occurrence, and the bed of the sea and the surface of the land are often altered by their tremendous violence. Seven active volcanoes are found at the southern extremity of the peninsula of Kamtschatka, and from thence the chain trends to the Kurile isles, where nine more are known to have been in eruption. Still southerly, the line extends to the Japanese group, where there are a considerable number, and where the disruption of the surface of the land in some districts is almost incessant, and sometimes violent. Passing the tropic of Cancer, the range embraces the Loo Choo archipelago, the Philippine and Ladrone islands, and is prolonged south to New Guinea. Here it branches off in a vast transverse line, extending on the one hand into the heart of the Pacific, and on the other through Java and Sumatra into the Bay of Bengal.

A third chain traverses the whole of the southern part of the European continent, a distance of above a thousand geographical miles. It commences at the Azores, and extends to the Caspian Sea, having for its northern boundaries the Tyrolian and Swiss Alps, and for its southern bounds the northern kingdoms of Africa. This district has frequently been visited with earthquakes, those of Lisbon and Calabria causing the whole continent to vibrate at the shock. Etna, Vesuvius, and Stromboli are at present the chief active vents, but anciently Vesuvius was in a state of torpor, and the island of Ischia was the scene of volcanic explosion. This small spot, about eighteen miles in circumference, now containing a population of twenty-five thousand, was frequently abandoned by its inhabitants on account of its violent convulsions. Before the Christian era, the Erythreans, the Chalcidians, and a colony established by Hiero king of Syracuse, were successively driven from it. Ischia however sunk into repose, which has not since been disturbed, only with one exception, when Vesuvius, in the year 79, burst forth from the stillness of ages, and overwhelmed the cities of Herculaneum and Pompeii with its ashes. The eruptions of Etna are mentioned as occurring from the earliest periods to which history and tradition extend. Thucydides speaks of three between the colonization of Sicily by the Greeks and the commencement of the Peloponnesian war in the year B. C. 431. It was a fable of the Greek mythology, that the giant Typhos was confined beneath Sicily, his outstretched limbs extending under the Italian peninsula, and the terrible natural phenomena of the region were assigned to the struggles of the imprisoned monster. Pindar, in his first Pythian ode, says: "The sea-girt heights above Cuma, and Sicily too, press upon his shaggy breast; and the pillar of heaven, snowy Etna, the perennial nurse of sharp pinching snow, holds him fast. From the recesses of Etna are vomited forth the purest streams of fire, immeasurable in extent. By day the fiery

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