Rensselaer Republican, Volume 25, Number 7, Rensselaer, Jasper County, 13 October 1892 — EARTHQUAKE WAVES. [ARTICLE]

EARTHQUAKE WAVES.

A Terrible Accompaniment of Earthquake. Frederick D. Chester, In Oct St Nicholas) While we usually think of earthquakes as taking place on land, they do, indeed, occur with equal devastation in the ocean. Thai point in the earth at which the explosion or breaking takes place is called the earthquake-focus; and from it what are known as earthquake-waves pass to the surface. What do these earthquakes resemble? Take a basin full of water, and dip a glass tube in it. Blow through the tube and you Will see bubles rising to the surface, and circular waves passing out. The disturbance at the bottom of the basin corresponds with the explosion or snappingof the crust at the earth-quake-focus, with this difference that instead of water waves, the latter produces earth-waves, passing through the ground. When the city of Lisbon, Portugal, was:destroyed, the earthquake took place in the bottom of the sea, fifty miles west of the city. Yet it so agitated the water that a wave sixty feet high dashed over Lisbon, destroying it and its inhabitants in a space of six minutes. Another earthquake, occuring just off the coast of Peru, made such a gigantic wave that a large vessel was thrown several miles inland. These are called earthquake waves. They are the largest known waves, and are caused by the heaving and rocking of the bed of the sea. In deep water such waves are not very high, but their motion extends far down into the ocean. When they reach shallower water, however, they heap up like a gigantic wall, and, with a force more terrible than fire or sword, they sweep on, bearing destruction witn them. Huge ships are tossed like straws far inland, or mingle their ruin with that of a harbor town. The Irish-Amealcans of New York are organizing for the erection of a monument in that city to the memory of Robert Emmet.