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Ch. XIX.] GREAT ERUPTION OF ST. VINCENT.
from which several estates never recovered; and so the 30th of April dawned in darkness which might be felt.
“Meanwhile, on the same day, to change the scene of the campaign two hundred and ten leagues, ' a distance,' as Humboldt says, 'equal to that between Vesuvius and Paris,' the inhabitants, not only of Caracas, but of Calabozo, situate in the midst of the Llanos, over a space of four thousand square leagues, were terrified by a subterranean noise, which resembled frequent discharges of the loudest cannon. It was accompanied by no shock, and, what is very remarkable, was as loud on the coast as at eighty leagues inland; and at Caracas, as well as at Calabozo, preparations were made to put the place in defence against an enemy who seemed to be advancing with heavy artillery. They might as well have copied the St. Vincent herd-boy, and thrown their stones, too, at the Titans; for the noise was, there can be no doubt, nothing else than the final explosion in St. Vincent far away. The same explosion was heard in Venezuela, the same at Martinique and Guadaloupe ; but there, too, there were no earthquake shocks. The volcanoes of the two French islands lay quiet, and left their English brother to do the work. On the same day, a stream of lava rushed down from the mountain, reached the sea in four hours, and then all was over. The earthquakes which had shaken for two years a sheet of the earth’s surface larger than half Europe were stilled by the eruption of this single vent.
“The strangest fact about this eruption was, that the mountain did not make use of its old crater. The originalvent must have become so jammed and consolidated, in the few years between 1785 and 1812, that it could
not be reopened, even by a steam-force the vastness of which may be guessed at from the vastness of the area which it had shaken for two years. So when the eruption was over it was found that the old crater-lake, incredible as it may seem, remained undisturbed, as far as has been ascertained. But close to it, and separated only by a knife-edge of rock some 700 feet in height, and so narrow that, as I was assured by one who had seen it, it is dangerous to crawl along it, a second crater, nearly as large as the first, had been blasted out, the bottom of which, in like manner, is now filled with water.
“The day after the explosion, 'Black Sunday,' gave a proof, but no measure, of the enormous force which had been exerted. Eighty miles to windward lies Barbadoes. All Saturday a heavy cannonading had been heard to the eastward. The English and French fleets were surely engaged. The soldiers were called out, the batteries manned, but the cannonade died away, and all went to bed in wonder. On the ist of May the clocks struck six; but the sun did not, as usual in the tropics, answer to the call. The darkness was still intense, and grew more intense as the morning wore on. A slow and silent rain of impalpable dust was falling over the whole island.
“The trade-wind had fallen dead; the everlasting roar of the surf was gone; and the only noise was the crashing of the branches snapped by the weight of the clammy dust. About one o'clock the veil began to lift, a lurid sunlight stared in from the horizon, but all was black overhead. Gradually the dust-cloud drifted away; the island saw the sun once more, and saw itself inches deep in black, and in this case fertilising, dust.
Ch. XIX.] GREAT ERUPTION OF ST. VINCENT. 355
“Those who will recollect that Barbadoes is eighty miles to windward of St. Vincent, and that a strong breeze from east-north-east is usually blowing from the former island to the latter, will be able to imagine, not to measure, the force of an explosion which must have blown the dust several miles into the air above the region of the trade-wind. Whether into a totally calm stratum or into that still higher one in which the heated south-west wind is hurrying continually from the tropics toward the pole.”* · I have quoted this graphic account of the great volcanic eruption of St. Vincent in 1812 from Canon Kingsley's delightful work to impress on my readers, in more eloquent language than I can command, the fact of great explosions having taken place in recent times similar in character, though much inferior in extent and force, to that by which I believe the great basin of the Lake of Masaya and similar basins in the same and adjoining Pacific provinces have been blasted out. I do not shut my eyes to the fact that great as was the force in operation in 1812 at St. Vincent, that necessary to excavate the great chasm at Masaya was incomparably greater. No one is more disinclined than I am to invoke the aid of greater natural forces in former times than are now in existence. But I believe there is good reason to infer that at the close of the glacial period volcanic energy was much more intense than now. So strained is the earth's crust at some parts that it is surmised that even a great difference in the pressure of the atmosphere such as occurs during a cyclone, may be sufficient to bring on an earthquake or a volcanic eruption already immi
* "At Last,” by Charles Kingsley, vol. i. p. 90.
nent. Whether this be so or not, there can be no doubt that at the melting away of the ice of the glacial period there was an enormous change in the strains on the earth's crust. Ice that had been piled up mountains high at the poles and along the chain of the Andes all through tropical America melted away and ran down to the ocean beds. This great transference of weight could not have been accomplished without many rendings of the earth's crust and many outpourings of lava and volcanic outbursts. Let us reflect, too, that not only was an enormous mass of matter, before lying over the poles, removed nearer to the equator, and many mountain-chains relieved of the ice of thousands and tens of thousands of years, but that there must have been an actual change in the earth’s centre of gravity. All our experience shows that the ice was more developed on some meridians than others; probably nowhere in the whole world did it lie so thick as along the American continents; and everywhere it must have been greater over the land than over the sea. When it assumed its liquid form, and arranged itself freely according to its specific gravity, the centre of gravity of the earth must have been effectively changed. All who have studied the present statical condition of the earth's crust will readily admit that such a change might produce greater volcanic outbursts than any known to history.
Then when we turn to the most ancient traditions of the human race in both the old and the new worlds, and find everywhere fire and water linked together in the accounts of the great catastrophes that are said nearly to have annihilated the human race, I for one am inclined to accept them, and to believe; that when, in the " Leo
VOLCANIC ORIGIN OF LAKES.
Amontli,” as translated by Brasseur de Bourbourg, we read of “the volcanic convulsions that lasted four days and four nights,” of “the thunder and lightning that came out of the sea,” of “the mountains that were rising and sinking when the great deluge happened,” and that when Plato on the other side of the Atlantic speaks of the earthquakes that accompanied the engulphment of Atlantis, we hear the dim echoes that have been sounding down through all time from that remote past, of the fearful volcanoes and earthquakes that terrified mankind at the time of the great cataclysm.
In these remarks on the origin of some of the lakes of Nicaragua I except the largest ones, namely, the lake of Managua and the great lake of Nicaragua, which probably occupy areas of depression produced by the large amount of material abstracted from below and thrown out by ancient volcanoes.