to, the ashes were carried to a distance of 300 miles on the side of Java, and 270 in the direction of Celebes. The darkness on the island of Java was so profound that it exceeded that of the darkest night. At a distance of forty miles from the volcano the ashes fell in such quantities that in spite of the minuteness of the particles they broke into the house of the resident at Bima, rendering that, as well as other houses in the town, uninhabitable. Immense quantities of stones of different sizes, mixed with ashes and sand, are now cast up from the mouth of the crater. In the eruption of Vesuvius which occurred in 1779, a huge red column of liquid lava, mixed with stones, was projected to a height, according to Sir William Hamilton, of 10,000 feet. This mass falling back on the mountain covered its whole cone, as well as part of the adjacent summit of Somma, with red-hot matter. The entire mass of fire was estimated to have had a breadth of two miles and a half; and the heat from it was felt at a distance of six miles. The projectile force occasionally exercised on these occasions may be judged of by the fact, that the volcano of Cotopaxi, in South America, ejected to a distance of eight or nine miles a mass of rock about one hundred cubic yards in volume. In 1822, Vesuvius threw out a mass of lava, of many tons in weight, to a distance of three miles. The eruption has now reached the point at which the molten lava begins to flow either over the crater or from lateral vents. It flows in a dark sluggish stream, being sometimes of great breadth and depth, and always carrying destruction in its path. At the eruption of Etna, which occurred in 1792, it is mentioned that the liquid lava streams were often thirty feet high, but where they passed over streams of old lava, they reached the height of 300 feet. At the eruption of the same volcano in 1832, a stream of lava flowed from one of the lateral craters towards the town of Bronte, eight miles distant. Within two miles of that town the stream extended to the breadth of one mile, and was thirty feet high, having then travelled in the course of its windings over a distance of eighteen miles. The town appeared to be in imminent danger, but fortunately the stream was diverted into another channel by the nature of the ground over which it had to pass.

frequently occurs from lateral vents than from the suminit of the craters. The lava currents from Vesuvius appear to flow with greater rapidity than those from Etna. In Iceland, where the heights of the volcanoes do not much exceed that of Vesuvius, the lava currents are remarkable for their magnitude and the rapidity of their current. River channels, from 400 to 600 feet in depth, and nearly 200 in breadth, are stated to have been filled up by them, and in the level country they have sometimes extended over areas varying from twelve to fifteen miles wide, and had a depth of 100 feet. The currents in some instances travelled forty and fifty miles. It has been calculated that the mass of lava poured out by the one volcano of Skaptar Jökul, in Iceland, during an eruption of two years' duration, would be sufficient to cover all the coal fields of the British islands to a height of twenty feet, or to bury London under a mountain rivalling the peak of Teneriffe.

It is mentioned by Mr. Stephens that the mountain of Izalco, in Honduras, which he (in 1839) estimates to have an elevation of 6000 feet, had been formed during the memory of the curate of Zonzonate. Only forty-one years before, this mountain existed as a small orifice, "puffing out small quantities of dust and pebbles." The volcano is in constant activity.

It remains to notice the torrents of mud which frequently accompany a volcanic eruption. They flow, sometimes with great violence, down the sides of the mountain, and are spread out at the foot over considerable areas, doing much damage to cultivated land. It was in such a stream that Herculaneum was in the first instance enveloped. The flanks of Etna have suffered much from the same cause. Mud torrents from mount Carguairazo, in South America, are said, on one occasion, to have covered a surface of about forty miles square. Similar streams from Tunguragua (in 1797) filled valleys 1000 feet wide to a depth of 600 feet. In South America, these streams have sometimes brought with them small fish, in such numbers as, it is believed, to have produced fevers by their decay. The formation of watery streams is ascribed partly to the condensation of large quantities of vapor severally discharged from volcanoes, and, in particular cases, to the melting of the snows which cover the higher volcanic mountains of the world. Rushing down the inclined

all loose matter which has settled on the cone, and deposit it at the foot. The presence of fish in the deposits is thus explained by Humboldt. He states that certain of the volcanic mountains of the Andes enclose large subterranean lakes, which communicate with the streams from the higher table-lands., Fish are thus introduced into the reservoirs, where they are said to multiply in an extraordinary manner. When the mountain is convulsed by a volcanie paroxysm, the waters find an exit through the fissures, and pour forth their contents over the plains. Thus the produce of volcanoes is distributed as sedimentary matter round their bases, and may enclose organic remains to yield future information to the geological inquirer.

The progress of the lava is generally very slow. In the instance just mentioned, the stream appears to have taken fourteen days or more to travel eighteen miles. Two miles in the first twenty-sides of the mountain, the streams carry with them four hours is mentioned as the rate at which a lava current flowed, which, in the year 1819, spread itself over the Val del Bove, at the foot of Etna. On the other hand, slow though its progress be, it continues in come cases to advance for a time after its first eruption, which appears almost incredible. Nine months after the first emission of the current just alluded to, it was observed by Mr. Scrope to be advancing at the rate of about a yard an hour. The rate of speed assumed by lava streams differs, however, according as they descend a more or less inclined surface. The height from which they are ejected appears to exercise a double influence; for lava springing from a low source is generally in a more liquid state than that from a more elevated crater; and craters of low elevation also throw out a much greater quantity of lava. The highest volcanoes of South America do not at present discharge lava; and in the case of those volcanic mountains which, rising to a considerable elevation like Etna and the peak of Teneriffe, continue to emit lava, it is remarked that this discharge more

The destruction of life from volcanic eruptions is not so great as might perhaps be expected from the magnitude of the phenomena, and when it does occur, it is as much, or more, owing to other causes than to the flow of lava. For lava is so

*Central America.

slow in its progress as generally to give time for escape. The lives lost in Pompeii and Herculaneum were few, and are to be attributed not to lava, which did not reach either of those towns at the time of their destruction, but to mud streams and aerial showers. "More havoc," says Sir C. Lyell, "is occasioned in a few years by the malaria fever of the Maremma of Tuscany, and of the Campagna of Rome, than by Vesuvian lavas in as many centuries." Perhaps no parts of the world are more richly cultivated, or support a more numerous population, than the neighborhoods of Vesuvius and Etna. This is not, however, to be attributed to immunity of the inhabitants from loss by volcanic eruptions. The experience afforded in South America shows that people are with difficulty driven from a spot otherwise suitable to them, and endeared to them through long association, by an amount of risk however great. The districts at the foot of Etna and Vesuvius have, at different times, suffered extensively from eruptions. Torre del Greco has been twice destroyed by lava, more than four hundred persons having perished on one occasion. In 1669, part of the town of Catania, at the foot of Etna, and fourteen other towns and villages, were destroyed by lava. Thucydides records three eruptions of Etna, by one of which Catania was injured; but the skirts of Etna appear to have suffered more from floods than from lava. In other parts of the world much damage has occasionally been done by volcanic eruptions. The island of Sumbawa was almost entirely depopulated by the eruption of 1815, only twenty-six persons out of a population of 12,000, having survived. The erup tion was accompanied by violent whirlwinds and extensive changes in the level of the land, to which the great loss of life may be chiefly attributed. In the island of Lancuok, one of the Canary islands, eruptions continued for five years (from 1730 to 1736). The lava appears to have flowed at first with unusual rapidity. Several villages were destroyed, and other damage ensued. Many of the inhabitants left the island. An eruption of Skaptar Jökul, in 1783, was also very destructive, particularly to animals.

We shall conclude our general description of the phenomena of volcanic eruptions with descriptions of particular eruptions. For the first, we borrow from "Squier's Geographical and Topographical features of Nicaragua.' The account refers to the volcano of Cozeguina, in Central America.

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On the morning of the 20th January, 1835, several loud explosions were heard for a radius of a hundred leagues around this volcano, followed by the rising of an inky-black cloud above it, through which darted tongues of flame resembling lightning. This cloud gradually spread outward, obscuring the sun, and shedding over everything a yellow sickly light, and at the same time depositing a fine sand, which rendered respiration difficult and painful. This continued for two days, the obscuration becoming more and more dense, the sand falling more thickly, and the explosions becoming louder and more frequent. On the third day the explosions attained their maximum, and the darkness became intense. Sand continued to fall, and the people deserted their houses, fearing the roofs would yield beneath the weight. This sand fell several inches deep at Leon, more than 100 miles distant. It fell in Jamaica, Vera Cruz, and Santa Fé de Bogota, over an area of 1500 miles in diameter. The noise of explosions was heard nearly as far, and the superintendent of Belize, 800 miles distant, mustered his troops, under the impression that there was a naval action off the harbor. All nature seemed

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overawed; the birds deserted the air, and the wild beasts their fastnesses, crouching terror-stricken and harmless in the dwellings of men. The people for a hundred leagues groped, dumb with horror, amid the thick darkness, bearing crosses on their shoulders and stones on their heads, in penitential debasement and dismay. Many believed the day of doom had come, and crowded to the tottering churches, where, in the pauses of the explosions, the voices of the priests were heard in solemn invocation to Heaven. The strongest lights were invisible at the distance of a few feet; and, to heighten the terrors of the scene, occa sional lightnings traversed the darkness, shedding a lurid glare over the scene. This continued for fortythree hours, and then gradually passed away. some leagues around the volcano the sand and ashes had fallen to the depth of several feet. Of course the operations of the volcano could only be known by the A crater had been opened, several miles in circumference, from which had flowed vast quantities Fonseca on the other. The verdant sides of the mounof lava into the sea, on one hand, and the gulf of tain were now rough, burned and seamed, and covered with disrupted roots and fields of lava. The quantity of matter ejected was incredible in amount. I am informed, by the captain of a vessel which passed along the coast a few days after, that the sea for fifty leagues was covered with floating masses of pumice, and that he sailed for a whole day through it, without being able to distinguish but here and there an open space of water. The appearance of this mountain is now desolate beyond description. Not a trace of life appears upon its parched sides. Here and there are openings emitting steam, small jets of smoke and sulphurous vapors; and in some places the ground is discharge of ashes, sand, and lava, was followed by a swampy from thermal springs. It is said that the flow of water; and the story seems corroborated by the particular smoothness of some parts of the slope. The height of this mountain is not, I think, more than 2500 feet. The anniversary of the cessation of this eruption is celebrated in the most solemn manner throughout all Central America.

Cotopaxi is one of the loftiest volcanoes of South America, and one of the most active. Its altitude is about 18,000 feet. It is situated in the province of Quito, at about thirty-six miles distance from the town of that name. Some of the phenomena of its eruptions have been described by Humboldt.

He says, that, in 1738, the flames of Cotopaxi rose 2700 feet above the brink of the crater. În 1744, the roarings of the volcano were heard as far as Honda, a town on the borders of the Magdalena, and at the distance of 600 miles. On the 4th of April, 1768, the quantity of ashes ejected by the mouth was so great, that, in the towns of Hambato and Tacunga, day broke only at three in the afternoon, and the inhabitants were obliged to use lanterns in walking the streets. The explosion which took place in the month of January, 1803, was preceded by a dreadful phenomenon―the sudden melting of the snows that covered the mountain. For twenty years before, no smoke or vapor, that could be perceived, had issued from the crater; and in a single night the subterraneous fire became so active that at sunrise the internal walls of the cone, heated, no doubt, to a very considerable temperature, appeared naked and of the dark color which is peculiar to vitrified scoriæ. At the port of Guayaquil, 156 miles distant, in a straight line from the crater, the noises of the volcano were heard day and night, like continued discharges of a battery, and they were distinguished on the Pacific Ocean to the south-west of Puna. The mass of

scoria and the huge pieces of rock thrown out of this volcano and spread over the neighboring valleys would form, says Humboldt, were they heaped together, a colossal mountain.

A remarkable volcanic explosion in Mexico has been recorded by Humboldt, when the volcano of Jorullo (having an elevation of between 1500 and 1600 feet above the surrounding plain) was raised in one night. Until the middle of the 18th century the plain from which this volcano rose consisted of cultivated fields. It was surrounded by basaltic mountains which seemed to indicate anterior volcanic convulsions. In June, 1759, frightful sounds proceeded from beneath the ground, accompanied by frequent earthquakes. These lasted fifty or sixty days, but had for some time ceased, when, on the 28th of September, they recommenced, and on the 29th, from three to four square miles rose up like a bladder. Flames spread over an area of from one to two miles square. Fragments of burning rock were thrown to prodigious heights; and, through a dense mass of cinders, the ground was seen by the light of the volcanic fire to be agitated like the sea. Two rivers, which before watered the plain, were precipitated into the burning crevices, and so incited the flames, that they were perceived on an extensive plain more than 4000 feet above the plain of the volcano. Eruptions of mud and clay, enclosing rounded masses of basalt, followed. Thousands of little cones, from six to nine feet high, rose from the surface, which, when visited by Humboldt, nearly fifty years afterwards, had a temperature of 203°; from some of them issued subterranean sounds, like those of a fluid in ebullition. Besides the chief mountain of Jorullo, five other hills, varying in height from 1200 to 1500 feet, rose from the saine crevice. Immense quantities of lava, both scoriaceous and basaltic were discharged, and the eruptions did not cease till the following February. The houses in Queretaro, 144 miles distant, were covered by the

cinders thrown up.

It seems that the great event we have described was due to the maledictions of certain capuchin monks, who, having been badly received by the owner of the land where the fires broke out, took this mode of repaying his inhospitality. The great heat is to be succeeded by as great cold. So, at least, relate and believe the native Indians of that


formed on the surface. Before the lava reaches the edge of the crater, these bubbles burst with a loud report, and quantities of red-hot scoriæ, accompanied by smoke and ashes, are thrown out with extraordinary swiftness. The liquid mass then, as if relieved, sinks again within the crater. The scoriæ, which are occasionally of several feet in diameter, are sometimes thrown to a height of 1500 feet. They either fall back again into the crater, or, being projected in a red-hot shower beyond the brink, roll into the sea. No flame is seen in the interior of the crater even at night, nor is the bursting of the globular masses accompanied by any appearance of this kind.

A cloud of smoke always hovers over the crater, and the sulphurous ingredients mingled with it frequently render approach inconvenient. Vapors arise not only from the crater, but from numerous apertures in other parts of the mountain. Quantities of dust pervade the air and fall at some distance from the foot of the mountain in showers like small hail. It appears to be produced by the trituration the scoriæ undergo, one against the other, either in the air or in the course of their descent towards the sea.

It is remarkable that, notwithstanding the incessant discharge of scoriaceous matter into the sea, its depth at the foot of the volcano appears to be unaltered. No doubt the frequent and violent storms, to which this part of the Mediterranean is subject, partly explain the circumstance. These seas appear, indeed, to have borne the same character from the earliest times; for the islands now known as the Lipari islands, formerly as Æolia, were the throne of Eolus, the god of the winds. Here, says Virgil *—

Vasto, rex Eolus, antro

Luctantes ventos, tempestatesque sonoras
Imperio premit, ac vinclis et carcere frenat.

But there is no allusion to a volcano, unless the
lines immediately following-

Illi indignantes, magno cum murmure montis
Circum claustra fremunt,

have reference to volcanic sounds.

Stromboli is a most useful beacon to sailors

navigating the neighboring sea. Its light is visible, at night, at a distance, it is said, of 100 miles.

A curious variety of volcanic eruption is when an This remarkable island is raised from the sea. occurrence has occurred more than once within recent times. Two new islands were raised from the sea near the Kurile Isles, in the beginning of the present century, one of which had an elevation of 3000 feet. These islands rose from a sea more

the sea in 1831.

No less worthy of attention than the eruption of Jorullo, are those which unceasingly occur from the volcanic mountain situated on Stromboli, one of the Lipari islands. This volcano has been in activity from the earliest times. It discharges at present only scoriaceous rock, for though lava con- than 200 fathoms in depth. Two islands also rose, stantly bubbles up in its crater, it does not pass beyond the brink. The island is about twelve at different times, near the coast of Iceland. In miles in circumference, and the volcano is situated 1811 an island (Sabrina) was thrown up to a at the north western side of it; the present crater height of 300 feet, off St. Michael's, in the Azores; being about half way up the acclivity. The total but it soon disappeared. Graham Island rose from height of the mountain is nearly 3000 feet, and it About a fortnight before the has two conical peaks; between them lies a plain, island appeared above the surface, shocks as of an which appears to have formerly been a crater of earthquake were felt in a vessel passing over the eruption. The present crater is of a circular form, spot. This was followed by waterspouts, and a and has a circumference of about 310 feet. The discharge of dense steam, which was said to have sides are composed of a confused mass of lavas, risen 1800 feet into the air. Finally, a crater made scoriæ, and sand, and contract internally to form an its appearance. When first seen, it had a height inverted cone. To a person looking into the crater only of twelve feet; it discharged scoriæ and imfrom above, the appearances are as follow: Red- mense columns of vapor. This was on the 18th hot liquid matter resembling melted brass is seen of July. By the 4th of August, it had risen to 200 whirling tumultuously round, which by degrees feet; after which it began to diminish, until, in rises towards the brink, whilst huge bubbles are *Eneid, 1. v. 12, et seq.

October, the island was nearly level with the sea. In 1833 there still existed a dangerous reef over the spot. The matter ejected by this crater consisted of scoriæ, pumice, and lapilli. No flow of lava occurred above the surface of the ocean, and the masses of matter rarely exceeded a foot in diameter; but from nine to eleven feet under water, the reef was found (in 1833) to consist in part of a black rock, which probably points out the line to which the solid material of the island rose.

The changes which have taken place in the Santorin Archipelago within historical times, afford perhaps the most interesting examples we have of the elevation of new islands.

The history of this volcanic group begins as far back as the year 233 B. C., which, referring to the Roman annals, would be in the time intervening between the first and second Punic wars. At this time, as we are informed by Pliny, the island of Therasia was separated from Santorin (the chief island of the group) by a great earthquake. Thirtyseven years afterwards, there arose a new island in the bay of Santorin. This island was christened, Hiera-Nesos-" the Sacred Island"-and still goes by the name of Hiera. In the year 19 of our era, a smaller island made its appearance close to the island of Hiera, to which it was subsequently united. In 726 and 1427, activity was displayed in increasing the size of Hiera. In 1573, a small island known as Micra-Kameni (the little burnt island) was added to the group. This island has a small cone and crater, 100 feet high.

Concerning the subsequent changes, we have more detailed information. M. de Thévenot, who visited the island of Santorin in 1655, relates what was told him of an eruption which occurred about eighteen years before. He says that the inhabitants were surprised one night by a violent noise, like distant cannonading, whence it was supposed that a naval engagement had taken place between the Venetian fleet and the Turks. It appeared, however, that the sounds proceeded from beneath the harbor. From morning till night pumice was thrown up with great violence and continued noise, and in such quantities that, when certain winds prevailed, the smallest vessels required the assistance of long poles to make a way for themselves out of the harbor. The air, too, was infected, so that several persons (says Thévenot) died, and many temporarily lost their sight. The sounds were heard on the island of Chios, distant more than 100 miles. Not only in Santorin, but at Chios and Smyrna, says the same authority, "all the silver became red, whether kept in coffers or in the pocket; and the religious who resided in those places told me that all their chalices became red. After some days the infection ceased, and the silver returned to its former color."

In 1650, after violent earthquakes, an eruption took place at some distance outside the bay of Santorin. No new island was raised, but the bottom of the sea was greatly elevated. Noxious vapors again made themselves known by killing more than fifty persons in Santorin, besides many animals. A wave fifty feet high arose, which broke on several of the neighboring islands. In Santorin it overthrew two churches, and exposed to view two villages, which had previously been overwhelmed by volcanic eruptions.

In 1707 and 1709, the submarine powers showed renewed activity, the consequence being the formation of two other small islands. The one was composed of white pumice, and obtained the name VOL. XXX. 2


of the White Island; the other, being composed of brown trachyte, was called, by contrast, the Black Island. The former island was subsequently cov ered, in great part, by the matter ejected from the latter, and the two islands now form one island, called Nea Kameni, (the Newburnt Island,) which has a cone 330 feet above the sea.

There is no reason to suppose that any diminution has taken place in the volcanic force having its seat under the archipelago of Santorin; it will not, therefore, be surprising should further changes take place, and other islands be added to the present number. Within the past half century, a striking change in the sea-bottom between the small Kameni and the island of Santorin has occurred. For, in 1830. MM. Virlet and Bory found a depth of only fe or four fathoms where, twenty years before, the depth had been fifteen fathoms; and this elevation had taken place over a limited area only of 800 by 500 yards, beyond which the sea deepened rapidly on all sides. Rea soning from the analogy of Vesuvius, whose present crater is within the much more extended crateriform depression of Somma, it is contended by Sir C. Lyell, that the islands of Santorin, Therasi, and Aspronisi, which encircle the present golf, are portions of a truncated cone, which formerly bounded one vast volcanic crater. He likens the formation of the small islands in the interior of the gulf to that of the modern cones of Vesuvius. By others the archipelago is considered to have been "a crater of elevation"-of the theory involved in which expression more will be said hereafter. It is a remarkable fact, that the southern part of Santorin is formed of granular limestone and argillaceous schist; the island being otherwise entirely composed of volcanic matter. The two formations are considered by Sir C. Lyell to be quite independent of each other. The volcanic mass which composes the islands consists of alternate beds of trachytic lava and tuff, which dip on every side from the centre of the bay towards the circumference, and in Santorin present precipices of from 800 to 1000 feet towards it. All the islands are covered with a white tufaceous rock, from forty to fifty feet in thickness.

We now return to the Vesuvian type of volcanic eruption, of which the following are interesting examples.

The island of St. Philip, better known since 1680 as Iltra do Fogo, (the Island of Fire,) belongs to the group of Cape Verde islands. It is nearly circular, and has a diameter of about fifteen miles. Until the year 1680, it was not suspected to contain within it a destructive power. In that year, however, a great earthquake, followed by a volcanic eruption, took place, and so alarmed the inhabitants, that some of them passed over to the neighboring island of Brava. From that time until 1799, the island of Fogo has suffered much from volcanic eruptions. They proceed from a peak in the middle of the island, which has an elevation of about 9000 feet. The eruption of 1785 has been described by Sr. J. da Silva Feijo, in a memoir presented to the Royal Academy of Sciences at Lisbon. He states that a great subterranean commotion, felt over the whole island, and accompanied by the loudest thunder-like noises, was the first sign of this eruption. The peak then opened perpendicularly, and having darted into the air, at intervals, columns of scoriæ, cinders and stones, closed again. Between the peak and the sea, on the eastern side, numerous other vents

made their appearance, whence flowed torrents of | Atlantic ocean and Europe together number fourlava, as well as cinders and smoke; the latter teen or fifteen. Two volcanic mountains are rising in the air, and darkening the whole neigh- believed (on the testimony of Chinese authorities) borhood. The principal mouths were at the base to exist in the Thian Shan mountains, in Central of the peak on the eastern side, and gave rise to Asia. In the Elburz chain of mountains to the four new mountains in the sarne line. These new south of the Caspian Sea, a lofty peak-the Peak elevations also opened vertically, and threw out of Demavend-is said to be an active volcano. immense quantities of lava, which, descending to- The Island of Zibbel Teir in the Arabian Gulf, wards the east, divided into two rivers of fire, one and that of Ormus in the Persian Gulf, are also of which filled up a large and very deep valley, said to have exhibited volcanic activity. and the other overflowed a wide plain, where there were houses and plantations. These were for the most part overwhelmed. The streams which flowed from vents nearer the sea also inundated a large portion of land; some entered the sea, and formed a rocky projection of considerable height, where formerly there had been a bay of from thirty to forty feet in depth. This eruption lasted thirty-right-hand side of the letter being formed by the two days.

A subsequent eruption of the same mountain (in 1799) has been described by Dr. Castilho. The second eruption began as usual by subterranean thunder, when a great vent opened on the skirts of the peak, giving issue to smoke, cinders and sand, and producing such an obscurity that the sun seemed to have set. Half an hour afterwards it began to rain sand, which covered the whole island to a depth of from four to five inches. A mixture of sand and cinders reached the island of Maio, distant nearly ninety miles. During the night the whole island appeared illuminated, and it was perceived in the town, at a distance of twenty-one miles from the volcano, that a great quantity of lava had begun to flow from the vent which had previously ejected only cinders and sand. The current flowed for twenty-seven days. It broke up large stones in its course, and filled up a river, converting it, by the cooling of the lava, into an oblong elevation. It carried away many houses as well as cattle, and destroyed farms. Finally it entered the sea at a distance of about thirty feet. A bay was also formed where formerly there had been a beach.

There is no certainty of the existence of any active volcanoes on the continent of Africa. The islands of Bourbon on its eastern side, and the islands of the South Atlantic (noticed below) on its western, contain active volcanoes.

The arrangement of the volcanoes in the basin of the Pacific, may be compared to the letter Q, the

volcanoes of the American continent, and the lefthand by those which skirt the Asian continent and Australia, bending round again towards the point whence they began.

The volcanoes of South America are arranged in linear groups. They commence with the Chilian group, in lat. 42°. The most southern of this group is Mount Osorno; the most northern, Maypu, which is not far from Santiago. Villarica, a volcano in constant activity, belongs to the group, which embraces at least five well-authenticated cases of active volcanoes. Just on the skirts of this district, in south lat. 32° 39', occurs the Nevado Aconcagna, which exceeds 24,000 feet in height, and is probably the highest in the world. Between 33° and 23° south lat., there do not occur any active vents.

The next centre of volcanic power is in Bolivia, between 18° 10′ and 16° 20′, where the Andes change their direction from being parallel to the meridian to one making an angle of 45° with that line. The mountains enclose the table-land_of Zitacaca, and rise to immense elevations. The Nevado de Sorata, not an active volcano, but the second highest mountain in South America, is found among them. Sehama and Somarape, which give slight symptoms of activity, also belong to the group. The volcano of Anguipa is found on the southern extremity of Peru, in lat 16° 24'.

We conclude this sketch of volcanic eruptions by mentioning the catastrophe which occurred in 1772, in the island of Java, when part of Papandayang, one of the loftiest volcanoes in the island, suddenly fell in, carrying with it about ninety We must pass over 13° of latitude to reach the square miles of ground. Forty villages were destroyed on the occasion; some being engulfed, and others covered up by ejected matter. Nearly 3000 of the inhabitants are said to have perished.

THE NUMBER, GEOGRAPHICAL DISTRIBUTION, AND HEIGHTS of the volcanoes now in action next demand our attention. So long as part of the earth remains unexplored by scientific persons, the actual number of volcanoes must be doubtful. All the calculations hitherto made must be regarded as approximations only to the truth. Accounts differ as to the number of volcanoes, even in parts of the world fully explored; some travellers classing as extinct, mountains which others regard as active; some giving as separate volcanoes what others class as vents subsidiary to some central mountain. Mr. Johnson gives the total number of active volcanoes as 270, which is probably the best approximation. Of this number, about three fourths occupy the islands or the shores of the Pacific ocean. A large number (about sixty) are found in the Indian ocean, occupying the Sunda Islands. The

* Physical Atlas,

next group of active mountains. They extend in a meridional line over 31°, and are found on both sides of the equator. The Peak of Sangay is the most southern, and that of Pastos the most northern volcano of the group. Six of them surround the table-land of Quito-Cayambe, Cotopaxi, Richincha, Antisana, L'Altar, and Tunguragua. Cayambe, whose summit is 19,535 feet above the sea, situated on the equatorial line. Cotopaxi is a most formidable mountain, by the frequency and magnitude of its eruptions. To the north of the equator occur Imbabura, Chiles, Cumbal, Tuqueres, Pastos, Sotara, and Purace.

We now pass to that portion of territory lying between the Isthmus of Darien and the Isthmus of Tehuantepec, which is called Central America. It is divided into three distinct parts-Costarica, Honduras, and Nicaragua, and Guatemala-each of which has a share of the thirty-nine active volcanoes which occupy the whole. These volcanic mountains are generally lower than those of the southern continent, and they are remarkably active. The district of Guatemala contains seventeen volcanic vents. The cities of Old and New Guatemala are situated at the foot of three of the most

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