Great Neapolitan Earthquake of 1857/Part II. Ch. XVIII
Chapter XVIII.
Moliterno.
A rapid descent by a pretty good track, brought us to Moliterno, about an hour after dark, wearied and wet, after more than fifteen hours’ walking and riding, twelve of which had been under heavy rain and wind. The Locanda here, though much shattered and in parts unsafe, was still tenantable, and I deemed myself happy in finding shelter and fire, for myself and my party.
Moliterno stands upon a low hill of hard and dense limestone, but generally without distinct evidence of bedding; in some spots to the east of the town there are indications of beds dipping to the west, with a moderate slope. The hill slopes rapidly towards the Sciavra, upon the south of the town, where are the ancient mills from which it derives its name. Monte Spagnoletto stands due north, and a little to the N. W. of it, distant about 212 Italian miles, while round thence to due west are the ridges of the lower Serras that shut out the high table land and basin of Lago Maorno. The town, situated in the midst of rich valleys, seems a thriving place. Several large modern buildings have suffered but little, and there are some in progress of erection. The people here show no lack of energy in clearing away the effects of the earthquake, which, however, has dealt very mercifully with them, in comparison with towns not five miles away. At the Locanda, situated in the higher part of the town, the barometer at 8:30, Naples time, 17th Feb. reads 27.05 inches, thermo. 51° Fahr.: it is 2696.7 feet above the sea. The highest point of the Colline on which the Castello is situated is about 200 feet above this, or nearly 2900 feet the summit.
In the new buildings in progress here, the causes of such facile destruction by shock as I have remarked, are patent; no thorough bond, thick and heavy walls of ill-constructed rubble, floor beams a yard apart, inserted only 9 inches into the walls, without "tossals" or wall-plates, want of all mutual connection between the walls, floors, and roof, and both the latter of prodigious weight.
The Chiesa Madre has its axial line nearly north and south, built of brick, with limestone pilasters, &c., and brick vaulted roof, about 160 feet by 45 feet wide and 60 feet high to the springing of the vault. The transepts are vaulted also. The arch is semicircular, and is fissured widely, down to the springing, and open an inch in places. The fissures in the walls, are fine and narrow, but give good indications; general direction of wave-path, from 140° to 145° E. of north, and the slope with vertical 10° to 12°, giving e = 11° from the N. W.
Nothing to indicate velocity. All around the church, are many ordinal buildings, fissured and partially thrown, and one large cardinal one, all of which indicated more or less distinctly, a wave-path from some point to the west of north to south; there were evidences, but obscure, of a minor and nearly orthogonal wave.
The Castello, consisting of heavy old massive masonry, much indurated, is severely fissured. General direction, 154° or 153° 30′ E. of north, but the extreme limits are very wide here, viz., from 105° to 165° E. of north. I have not taken a mean, but a choice, of those fissures whose direction appeared least likely to have been influenced by curvature (as in the great round towers) or other disturbing conditions. The fissures in the great towers of 80 feet in height or thereabouts, were open 212 inches at the top. The walls were very thick, and such that this width, is a rude indication of the amplitude (horizontal) of the wave here.
The Chiesa, della Santa Dominica della Rosario, has its axial line 120° E. of north, or not far from cardinal: it is about 160 feet long and 50 feet wide, with a brick semi-cylindrical vaulted roof, 40 feet to the soffit, which, with the walls, are heavily fissured: the mean of seven pairs of these, gives a general wave-path of 155° E. of north, and an emergence from the north of 13° 30′, the extreme limits being 10° and 17°. In this building there is evidence also in the vault fissures, of a subordinate shock, nearly at right angles to the main one.
On altars, both at the north and south sides of the church, I found wood gilded candlesticks, that had been thrown out of plumb. Those on the north side had been thrown towards the N. W. at various angles, and still leaned against the back wall or shelf of the altar. They were high up and out of reach. Those on the south of the church, I found now in their usual places, but the Sacristan informed me, that all the wood candlesticks at that side, had been thrown quite off the altar, and were found scattered about the floor, and had been since replaced.
These are decisive as to direction of the wave here, viz., from a point W. of north towards the south. The candlesticks at the north side, thrown by the first semiphase of the wave, were limited in motion, by the wall against which they fell and leaned, having gone over too far to recover their position at the return stroke. Those at the opposite, or south side, were at the same moment thrown out of plumb forwards, or towards the front of the altar, and finding no wall to support them, fell altogether.
In the Caffé of Gaetano Mallione, a number of bottles of the form of foreign wine bottles, full to the corks of Rosolio, stood upon a shelf, at 8 feet high from the floor, running along the west side of a wall, whose length was N. 155° east. The owner, an intelligent fellow, replaced the bottles for me in the position in which he stated he had found them in the morning after the shock. (Sketch No. 243, Coll. Roy. Soc.) Those towards the back of the shelf, (which was about 15 inches wide), leaned back against the wall, and against each other, sloping towards the east and south. Several that had stood upright close to the edge of the shelf, (which had a little ledge or curb of about three-quarters of an inch high, rising at its front edge), had been pitched over and thrown upon the floor and broken. The spots upon which these had landed, I found were on the average, three feet horizontally from where the bottles had stood on the shelf. The direction of throw was about 125° E. of north towards the N. W.; omitting one, thrown in the apparent direction to .
If we assume the emergence to have been 15° here, we have
and the normal velocity of the wave here given by the equation
is 10.8 feet per second, neglecting the velocity necessary to upset the bottle from its base, which should be added, and would increase the velocity per second a foot or two. We cannot rely upon this for more, than a general indication, that the velocity here was not materially different from further west and north, and I could get no better data at this town.
I could obtain but very confused accounts here, of the second shock, (that of an hour or so after the great one,) many persons saying they did not feel any such, nor could I obtain any good account of the sounds; all agreed that they heard the "rombo." I was unfortunate, however, in not being able to find the Syndic or Judice, both of whom were absent.