Peculiar Results* of Earthquakes

New Zealand Tablet, Volume XXXV, Issue 48, 28 November 1907, Page 30

Peculiar Results* of Earthquakes

The recent seismic disturbances in the South of Italy and in South America, following so closely the terrible- catastrophes in Jamaica, .Valparaiso, and San. Francisco, forcibly [ draw attention -to the fact that, despite~~the great strides science has made of late, little or nothing .has been .discovered respecting the mighty forces imprisoned within the earth, and to the outbreak of which these fearful disasters are 'due.** . Scientists certainly cannot complain of . lack of ' opportunity, since records have been preserved , of over 7,000 earthquakes severe, enough to merit remembrance, and by which more than 14,000,000 people are estimated to have perished. Some idea of the power ,of these subterranean forces is shown by the changes , effected by them -in geography. Mountains have been obliterated or new ones formed, "islands have been made or - destroyed, and whole stretches of coastline wiped oufc, For instance, in . September, 1759, on the lofty tableland about 150 miles south-west of the city of - Mexico, a piece of land four square miles in area was suddenly raised 550 ft, and numerous cones appeared, one of them — the volcano of Jorullo— being nearly i,7ooft high. Java, in 1772, suffered in the opposite way, for _a tract of country fifteen miles long by six broad was swallowed up entirely, a mountain of 9,000 ft being reduced to s,oooft' only r in the process. In 1822 a great earthquake in Chili produced a permanent elevation of irom 2ft to 7ft over nearly 100,000 square miles of the country between the Andes and the coast, and geologists have discovered traces of. sea-beaches _at •a- distance inland - which prove that such upliftings must have occurred previously several times. " In the disaster at Lisbon in 1755, when nearly the whole city was wrecked in six minutes, and over 50,000 people' perished, the largest mountains in Portugal were shaken to their very foundations, great masses being hurled into the adjacent valleys. A new quay, built" of marble, on . which a; huge crowd assembled for safety from the falling buildings, . suddenly sank, and it is recorded that not one of the 'dead ■bodies came to the surface. Moreover, of the ships engulfed no wreckage floated, and the spot, though previously -comparatively shallow, was afterwards stated to be unfathomable. An hour after the town had been shattered the sea suddenly retired so far as to leave the bar at the entrance of the-Tagus dry, and then rolled in with a series of gigantic waves from 40ft to 60ft higher than the highest tide, completely swamping the city. The effect of this earthquake was felt over an area of upwards of 7,000,000 square miles, and the velocity with which, the shock travelled was computed at about twenty miles per minute. A district which has experienced the most extraordinary changes from earthquake is the valley of the Mississippi, which in 1811-12 was convulsed to 'such a degree that new islands, and lakes twenty miJes in extent, were formed in the incredible space of an hour, while other lakes were drained quite dry. The cemetery at New Madrid was precipitated into the river, and the ground on which the town is built, and the bank for fifteen miles above, sank Bft. For years afterwards the forest presented ' a singular scene of confusion, the trees standing inclined in every direction, and many having their trunks and branches broken.' About the same time Caracas experienced violent shocks. The surface undulated like a boiling liquid, and terrific - subterranean sounds were heard. The whole city, with its magnificent churches, was ruined almost in a moment, and nearly" 12,000 inhabitants were slain. Caracas has been called the city of earthquakes, and it is estimated that the damage caused by them is equal to an annual charge of 16s per head on the population. In an earlier earthquake at the same place, ' in 1790, a large part of the forest of Aripoa sank, forming ■a lake 800 yds in diameter and 80ft deep. An instance of the opening and closing of 'fissures is afforded by the "Calabrian earthquake of 1783, which lasted ior nearly four years. It is stated that men and cattle were -engulfed by cracks in the surface, and in some cases thrown out again alive by the next shock, with great jets of mud and water. History repeats itself curiously, for one chronicler of these earthquakes relates that numbers of miscreants, were seen robbing the dead and dying, even stripping them of 'their clothes ; and more than a century later the same thing takes place under almost identical circumstances at San Francisco. >

owing year.

Another remarkable incident is recorded. Near^ Seminara an extensive olive ground and orchard were, hurled by one of the "shocks a distance of 200 ft into a valley 60ft in depth. A small inhabited house standing on the land went with it without injury to the building or occupants. Moreover, the olive trees continued to grow, and bore a good crop the following year. - ' • ' J '■•''■•" Hindustan has had many important geological changes effected*- by earthquakes. In 1762 Chittagong was violently shaken, the earth opening in niariy places and throwing up "water, and mud of sulphureous smell. Then sixty square "miles of coast suddenly and permanently subsided, one of the Mug Mountains entirely disappeared, and' another sank so low that only the summit remained. At the same time a corresponding rise of ground took place at Ramree, an island' further along the .coast. Again", at Cutch, in 1819, the fort and village of Sindree were submerged, and about five miles distant' a long, elevated mound was raised, measuring some fifty miles, by- sixteen in places, out of what had been a perfectly level plain.