EARTHQUAKE AT THE CARACCAS.

(Jamieson's Universal Science.)

ON the subject of earthquakes, the field of observation is both varied and extensive; but the scientific description of one is worth the detail of fifty, where the marvellous hath supplied knowledge, and fear has shrunk from the investigation of the causes that produce these phenomena.

There are few events in the physical world which are calculated to excite so deep and permanent an interest as the earthquake which destroyed the town of Caraccas in 1812, and by which more than 20,000 persons perished, almost at the same instant, in the province of Venezuela, in South America.

The 26th of March was a remarkably hot day.

The air was calm, and the sky unclouded.

It was Holy Thursday, and a great part of the population was assembled in the churches.

Nothing seemed to presage the calamities of the day.

At seven minutes after four in the afternoon the first shock was felt; it was sufficiently powerful to make the bells of the churches toll; it lasted five or six seconds, during which time the ground was in a continual undulating movement, and seemed to heave up like a boiling liquid.

The danger was thought to be past, when a tremendous subterraneous noise was heard, resembling the rolling of thunder, but louder, and of longer continuance than that heard within the tropics in in time of storms.

This noise preceded a perpendicular motion of three or four seconds, followed by an undulatory movement somewhat longer.

The shocks were in opposite directions, from north to south, and from east to west.

Nothing could resist the movement from beneath upward, and undulations crossing each other.

The town of Caraccas was entirely overthrown.

Between nine and ten thousand of the inhabitants were buried under the ruins of the houses and churches.

The procession had not yet set out; but the crowd was so great in the churches, that nearly three or four thousand persons were crushed by the fall of their vaulted roofs.

The explosion was stronger towards the north, in that part of the town situated nearest the mountain of Avila, and the Silla.

The churches of la Trinidad and Alta Gracia, which were more than 150 feet high, and the naves of which were supported by pillars of twelve or fifteen feet diameter, left a mass of ruins scarcely exceeding five or six feet in elevation.

The sinking of the ruins has been so considerable, that there now scarcely remain any vestiges of pillars or columns.

The barracks, called El Quartel de San Carlos, situate farther north of the church of the Trinity, on the road from the custom-house de la Pastora, almost entirely disappeared.

A regiment of troops of the line, that was assembled under arms, ready to join the procession, was, with the exception of a few men, buried under the ruins of this great edifice.

Nine tenths of the fine town of Caraccas were entirely destroyed.

The walls of the houses that were not thrown down, as those of the street San Juan, near the Capuchin Hospital, were cracked in such a manner, that it was impossible to run the risk of inhabiting them.

Estimating at nine or ten thousand the number of the dead in the city of Caraccas, we do not include those unhappy persons, who, dangerously wounded, perished several months after, for want of food and proper attention.

The night of Holy Thursday presented the most distressing scene of desolation and sorrow.

That thick cloud of dust, which, rising above the ruins, darkened the sky like a fog, had settled on the ground.

No shock was felt, and never was a night more calm or more serene.

The moon, nearly full, illumined the rounded domes of the Silla, and the aspect of the sky formed a perfect contrast to that of the earth, covered with the dead, and heaped with ruins.

Mothers were seen bearing in their arms their children, whom they hoped to recall to life.

Desolate families wandered through the city, seeking a brother, a husband, a friend, of whose fate they were ignorant, and whom they believed to be lost in the crowd.

The people pressed along the streets, which could no more be recognised but by long lines of ruins.

All the calamities experienced in the great catastrophes of Lisbon, Messina, Lima, and Riobamba, were renewed on the fatal day of the 26th of March, 1812.

The wounded, buried under the ruins, implored by their cries the help of the passers by, and nearly 2000 were dug out.

Implements for digging, and clearing away the ruins were entirely wanting; and the people were obliged to use their bare hands to disinter the living.

The wounded, as well as the sick who had escaped from the hospitals, were laid on the banks of the small river Guayra.

They found no shelter but the foliage of the trees.

Beds, linen to dress the wounds, instruments of surgery, medicines, and objects of the most urgent necessity, were buried under the ruins.

Every thing, even food, was wanting during the first days.

Water became alike scarce in the interior of the city.

The commotion had rent the pipes of the fountains; the falling of the earth had choked up the springs that supplied them; and it became necessary, in order to have water, to go down to the river Guayra, which was considerably swelled; and then vessels to convey the water were wanting.

There remained a duty to be fulfilled towards the dead, enjoined at once by piety and the dread of infection.

It being impossible to inter so many thousand corpses, half buried under the ruins, commissaries were appointed to burn the bodies: and for this purpose, funeral piles were erected between the heaps of ruins.

This ceremony lasted several days.

Amid so many public calamities, the people devoted themselves to those religious duties which they thought were the most fitted to appease the wrath of heaven.

Some, assembling in procession, sung funeral hymns: others, in a state of distraction, confessed themselves aloud in the streets.

In this town was now repeated what had been remarked in the province of Quito, after the tremendous earthquake of 1797; a number of marriages were contracted between persons who had neglected for many years to sanction their union by the sacerdotal benediction.

Children found parents by whom they had never till then been acknowledged; restitutions were promised by persons, who had never been accused of fraud; and families, who had long been enemies, were drawn together by the tie of common calamity.

If this feeling seemed to calm the passions of some, and open the heart to pity, it had a contrary effect on others, rendering them more rigid and inhuman.

Shocks as violent as those which, in the space of one minute, overthrew the city of Caraccas, could not be confined to a small portion of the continent.

Their fatal effects extended as far as the provinces of Venezuela, Verinas, and Maracaybo, along the coast; and still more to the inland mountains.

La Guayra, Mayquetia, Antimano, Baruta, La Vega, San Felipe, and Merida, were almost entirely destroyed.

The number of the dead exceeded four or five thousand at La Guayra and the town of San Felipe, near the copper-mines of Aroa.

It appears, that it was on a line running east north-east, and west south-west, from La Guayra and and Carraccas to the lofty mountains of Niquitao and Merida, that the violence of the earthquake was principally directed.

It was felt in the kingdom of New Granada from the branches of the high Sierra de Santa Martha as far as Santa Fe de Bogota and Honda, on the banks of Magdelena, 180 leagues from Carraccas.

It was every where more violent in the Cordilleras of gneiss and mica-slate, or immediately at their foot, than in the plains: and this difference was particularly striking in the savannahs of Varinas and Casanara.

In the valleys of Aragua, situate between Carraccas and the town of San Felipe, the commotions were very weak: and La Victoria, Maracay, and Valentia, scarcely suffered at all, notwithstanding their proximity to the capital.

At Valecillo, a few leagues from Valencia, the earth, opening, threw out such an immense quantity of water, that it formed a new torrent.

The same phenomenon took place near Porto-Cabello.

On the other hand, the lake Maracaybo diminished sensibly.

At Coro no commotion was felt, though the town is situated upon the coast, between other towns which suffered from the earthquake.

The duration of the earthquake, that is to say, the whole of the movements of undulation and rising which occasioned the horrible catastrophe of the 26th of March, 1812, was estimated by some at fifty seconds, by others at one minute and twelve seconds.

Fifteen or eighteen hours after the great catastrophe, the ground remained tranquil.

The night, as we have already observed, was fine and calm; and the commotions did not recommence till after the 27th.

They then were attended with a very loud and long continued subterranean noise.

The inhabitants of Caraccas wandered into the country; but the villages and farms having suffered as much as the town, they could find no shelter till they were beyond the mountains of Los Teques, in the valleys of Aragua, and in the Llanos or savannahs.

No less than fifteen oscillations were often felt in one day.

On the fifth of April there were almost as violent an earthquake, as that which overthrew the capital.

During several hours, the ground was in a state of perpetual undulation.

Large masses of earth fell in the mountains; and enormous rocks were detached from the Silla of Caraccas.

It was even asserted and believed that the two domes of the Silla sunk fifty or sixty toises; but this assertion is founded on no measurement whatever.

On the 7th day of June, 1692, the town of Port Royal in Jamaica, was in two minutes totally destroyed by an earthquake:

Various instances of the destructive effects of this terrible phenomenon might be adduced, but the preceding have exceeded the limits assigned for this portion of our Museum.