The New Student's Reference Work/Izalco, Mount

Izalco (ēs-äl′-kō), Mount, a remarkable volcano, 36 miles northwest of the city of San Salvador.  It is near a group of extinct volcanoes, 6,000 feet high.  Its first eruption occurred in 1770 during an earthquake.  The eruptions are almost incessant and of unusual violence, and are visible far out at sea.  Sailors call it the lighthouse of San Salvador.  Izalco, with the exception of Jorullo in Mexico, is the only known volcano that has arisen from the level of the plain in the memory of man.  In 1798, after a series of earthquakes, dust and pebbles were seen rising from an opening in the plain.  Soon after, lava was thrown up, and this, together with huge stones, slowly piled up around the opening till the vast cone, as it now stands, was formed.