Page:Popular Science Monthly Volume 28.djvu/842

822 on the flanks of Izalco, a volcano which has had since its formation in 1770 an eruption about every twenty minutes and twenty-one considerable ones, has never been destroyed, nor have Santa Anna, San Miguel, and Masaya, on the slopes of the volcanoes of the same names, which have had respectively seven, ten, and six great eruptions. San Salvador, which is built on the slopes of Quetzaltepec, has been wholly destroyed fourteen times, the last time on the 19th of March, 1873. This volcano may be regarded as extinct, for it has had only one eruption since the conquest, that of the 30th of September, 1659, when the cinders flew as far as Conmyagua, the capital of Honduras, and the lavas formed the immense "bad land" (cheyre) of Quetzaltepec and buried the Indian city of Nejapa. The principal of the eight craters of Quetzaltepec (or San Salvador as it is otherwise called) is remarkable for its perfect regularity and its size, six hundred metres in diameter and depth. The bottom is occupied by an almost inaccessible lake. The appearance of the volcano of Lake Ilopango, in 1879-'80, probably saved San Salvador from a fifteenth destruction. Omoa and Jucuapa, built on the slopes of the extinct volcanoes of the same names, were destroyed on the 4th of August, 1856, and the 2d of October, 1 878.

In a work published by the Government of San Salvador on "Earthquakes and Volcanic Eruptions in Central America," in which I have given a detailed history of the phenomena, I have been able to show, from original documents, that the destruction of Guatemala, on the night of the 10th and 11th of September, 1541, was due, not to an eruption of mud from the extinct volcano of Agua, as some authors suppose, but to the rupture under the weight of the water, assisted by an earthquake, of the walls of its crater, which had been filled by the extraordinary rains of the preceding days. The eruption of Pacaya, on the 18th of February, 1651, and the ruin of Guatemala, which it occasioned, were accompanied by the spectacle of frightened wild animals seeming to seek the protection of man, as they did also during the eruption of Coseguina on the 20th of January, 1835. The year 1770 witnessed the rise of Izalco—"the Lighthouse of the Pacific"—a magnificent volcano, whose eruptions have since followed one another uninterruptedly about every quarter of an hour, with explosions that are frequently heard for ten leagues around. The great eruption of Coseguina, on the 20th, 21st, 22d, and 23d of January, 1835, perhaps one of the most formidable eruptions mentioned in history, the cinders from which flew as far as to Vera Cruz, Havana, Carácas, and Bogotá, was heard over the same circle of seventeen hundred miles in diameter. The well-proved coincidence that these eruptions began on the same day with those of the Chilian volcanoes of Aconcagua and Corcovado, all three situated in the chain of the Andes, is too remarkable not to attract attention. The environs of the active volcano of Momotombo from the 1st to the 20th of April, 1850, witnessed the emergence of the new volcano of Las Pilas, now extinct.