Peter Parley's Wonders of the Earth, Sea, and Sky

by Samuel G. Goodrich

EARTHQUAKE OF CALABRIA.

The shocks began in 1783, and lasted for nearly four years, till the end of 1786. During this time the King of Naples sent persons to take correct notes and representations of all that was going on, and we have therefore got a better account of it than we have of any other Earthquake that ever occurred.

The convulsion of the earth, sea, and air, extended as far as Naples, and over the whole of Sicily; but the district over which it was so violent as to excite intense alarm, was about five hundred miles in circumference.

"The first shock of February 5th, 1783, threw down, in two minutes, the greater part of the houses in all the cities, towns, and villages, from the western sides of the Apennines in Calabria Ultra, to Messina in Sicily, and convulsed the whole surface of the country. Another occurred on the 28th of March, with almost equal violence. The chain of granite mountains which passes through Calabria from north to south, and attains the height of many thousand feet, was shaken but slightly; but it is said that a great part of the shocks which were spread with a wave-like motion through the recent strata from west to east, became very violent when they reached the point of junction with the granite, as if a reaction was produced where the wave-like movement of the soft strata was suddenly arrested by the more solid rocks. The surface of the country often heaved like the billows of a swelling sea, which produced a swimming in the head like sea-sickness. It is particularly stated, in almost all the accounts, that just before each shock the clouds appeared motionless; and although no explanation is offered of this phenomenon, it is obviously the same as that observed in a ship at sea when it pitches violently. The clouds seem arrested in their career as often as the vessel rises in a direction contrary to their course; so that the Calabrians must have experienced precisely the same motion on the land."

At Messina in Sicily, the shore was rent; and the soil along the port, which before the shock was perfectly level, was inclined towards the sea, and the sea itself was considerably deeper, which showed that the inclination must have been occasioned by the bottom's sinking. The quay also sunk down 14 inches below the level of the sea, and the houses in the neighbourhood were much cracked.

In one town there was a large round tower of great strength, which was divided by a perpendicular rent, and one-half was raised up several feet, so as to show the foundations. Those who saw it, said that it looked like a great tooth half extracted, showing the fangs. Along the line of the crack, the walls were found to fit so exactly together, that you would not have known they had even been divided if the courses of the stones had not been disturbed.

There was a very curious difference between some of the walls which had been thrown down, or very much shaken by some of the shocks. In some of them, the separate stones were parted from the mortar, so as to leave an exact mould where they had rested; and in others, the mortar was ground to dust between the stones. It was not less strange to see the effect of what must have been whirling movements in the ground. In some streets, one house would be thrown down, and leave the rest uninjured; while in others, all the houses but one were thrown down, and that one remained firm and unmoved. Two obelisks were twisted round, so that the stones of which they were composed, stood at cross purposes. This cut represents one of the two, as it stood after the earthquake, and before.

"It appears evident that a great part of the rending and splitting of the ground was the effect of a violent motion from below upwards; and in a multitude of cases where the rents and chasms opened and closed alternately, we must suppose that the earth was by turns heaved up, and then let fall again. We may conceive the same effect to be produced on a small scale, if, by some mechanical force, a pavement composed of large flags of stone should be raised up and then allowed to fall suddenly, so as to resume its original position. If any small pebbles happened to be lying on the line of contact of two flags, they would fall into the opening when the pavement rose, and be swallowed up, so that no trace of them would appear after the subsidence of the stones. In the same manner, when the earth was upheaved, large houses, trees, cattle, and men were engulfed in an instant in chasms and fissures; and when the ground sunk down again, the earth closed upon them, so that no vestige of them was discoverable on the surface. In many instances individuals were swallowed up by one shock, and then thrown out alive, together with large jets of water, by the shock which immediately succeeded."