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In the history, and especially the political history, of the earthquake, attention will be drawn more to Messina, with its heavy deathroll, than to the smaller towns of the opposite coast. But the intensity of the shock was greater at Reggio and the surrounding villages than in any part of Sicily. Not that the ruin of the Calabrian towns was more complete, for that could hardly have been the case, but the railway-lines were damaged more seriously and over a wider area, the distortion of the ground was more marked, the sea-waves were higher and the after-shocks more frequent. In all probability, the seismic focus extended beneath the whole width of the straits—the south-western end being situated close to Messina ; another and more important part reaching to and beyond Reggio; while, in the intermediate region, there must also have been a very considerable displacement of the ocean-bed sufficient to rupture the submarine cables and to generate the seismic sea-waves.
If the Messina earthquake were an isolated phenomenon--if it had occurred, like the Charleston earthquake of 1886, in a country where earthquakes are almost unknown-it would still be one of the highest interest to seismologists. But this interest is still further increased from its occurrence in a land of earthquakes, from its connexion with the great convulsions which have made the names of Reggio, Palmi, and Monteleone familiar in the annals of disaster. Of few seismic districts is the history so well known as that which embraces the south of Calabria and the north-east of Sicily. It has been investigated by many students, but especially by Dr. G. Mercalli, professor of vulcanology in the university of Naples, and by Dr. M. Baratta, the historian of Italian earthquakes. The tale of disaster begins with the earthquake of Catania in 1169, when 15,000 persons were killed. In 1509 Reggio was destroyed. In 1638 nearly 10,000 persons were killed in Nicastro and the surrounding villages. In 1693, 93,000 lives were lost during the earthquake which devastated the north and east of Sicily. Few earthquakes are so well known as the series which lasted from February 1783 until October 1786, and during which more than 30,000 persons were killed. In the nineteenth century, many strong shocks, though not of the first order of magnitude, occurred, culminating in that of the 16th of November 1894, which resulted in the loss of ninety-six lives. In the present century, besides the subject of this paper, there have been the earthquake of the 8th of September 1905, and also that of the 23rd of October 1907, which originated in an almost inactive centre to the south of Gerace.
The different earthquake zones of southern Calabria have recently been delineated with great care by Dr. M. Baratta, part of whose map is reproduced on a smaller scale in fig. 2. The continuous lines bound the areas most strongly shaken by the earthquakes of 1783; the broken lines are the corresponding curves for the earthquake of 1905; the dotted lines indicate four districts on the eastern coast with which the recent earthquake seems to have had no connexion. It is possible, of course, that the excessive damage in some of these areas may have been due to local conditions, but the fact that those affected in 1783 were shaken successively points to the existence of more or less detached centres of maximum activity ; while the fact that they were disturbed simultaneously, or nearly so, in 1905 indicates that there must be some deep-seated connexion between them. Again, while the earthquake
of 1905 was thus polycentric, some of the zones were affected singly by certain earthquakes—for instance, the Palmi zone in 1894, the Monteleone zone in 1659, the Nicastro zone in 1638, the Cosenza zone in 1854, and the Bisignano zone in 1836.
The earthquakes of 1783 are the most remarkable of all those which have desolated the Calabrian towns. Their number must have been immense, for in Monteleone alone 950 shocks were recorded
before the end of the year. Their destructiveness was increased by the rapid and unexpected migrations of the seismic focus. The first great shock originated in the Palmi zone on the 5th of February, and rivalled the recent earthquake in such high death-rates as 77 per cent. at Terranova, 59 per cent. at Bagnara, and 51 per cent. at Oppido. A few hours later, the next great shock occurred in the Scilla zone; two days afterwards came a third in the Monteleone zone, followed in two hours by a fourth, which, though less violent, is interesting as one of the few earthquakes which belong to the zone chiefly affected at the close of last year. The boundary of the central area of this shock is represented by the dotted line in fig. 1, which coincides in part with the Messina and Palmi areas of 1908. The fifth shock occurred on the 1st of March in the Monteleone zone, and was succeeded by a sixth shock on the 28th of March in the Girifalco zone, hardly, if at all, inferior in strength to that of the 5th of February, but resulting in fewer deaths, as most persons at that time were living in sheds.
If the curves in the two maps are compared, it will be seen that the earthquake of 1908, like its predecessor three years before, was a polycentric earthquake, though affecting fewer zones. On the whole, there is a distinct southerly migration of seismic activity. The foci corresponding to the Monteleone and Palmi zones were both disturbed, but the most important centre was one that has very rarely been active, and never before, so far as known, with such annihilating strength. It is, moreover, the only zone of the series which is largely submarine, and thus the local seismic sea-wave is a feature that is almost unknown on the Calabrian shores. Indeed, the absence of any marked zone beneath the Straits of Messina has been urged as an objection to Professor Suess' theory of the origin of the earthquakes in southern Italy.
Professor Suess, the veteran author of The Face of the Earth, was one of the first geologists to recognise the intimate connexion between earthquakes and the forces moulding the earth's crust, and southern Italy is perhaps the seismic region which he has studied in greatest detail. The masses of ancient rock composing Aspromonte, the hills of Vaticano, Scilla, and the Peloritan mountains near Messina, he points out, are the fragments of a mountain range that was once continuous, but is now cut through by the Straits of Messina. In southern Calabria they are bounded on the western side by a great fault or fracture, along which were situated the centres of the earthquakes of 1783, and of many others before and since. This band of centres is represented by the broken lines in fig. 1. It is part of a great curve, roughly circular in form, with its centre among the Lipari
, Isles, and a radius of about sixty miles. Professor Suess has also indicated the existence of several rectilinear earthquake bands, radiating from the Lipari Isles, and crossing the circular band nearly at right angles.
Between the Lipari Isles and the mainland and Sicily, lies part of the Tyrrhenian Sea, the bed of which, according to Professor Suess, has sunk down in the form of a dish, bounded by the curvilinear fracture, and producing by its subsidence the radial fractures which converge towards the still active volcanoes of the Lipari Isles. Further sinking of the basin, which tends to widen the Straits of Messina, gives rise to earthquakes in Calabria and Sicily, and to increased volcanic activity in the Lipari Isles.
It is by no means necessary that the subsidence should take place throughout the whole fracture at once. It may, on some occasions, as in 1659 and 1894, be confined to small portions ; or, as in 1783, it may affect different regions in succession, the foci migrating to and fro along the curved bands; or lastly, as in 1905 and 1908, it may occur over a great extent of the fracture and visit several or many portions simultaneously.
Professor Suess' theory is attractive in its simplicity, and in its power of grouping together facts that are apparently isolated. It is possible that it may be expressed in too simple a form-that, with the advance of knowledge, it may require extension or modification. The course of the curvilinear fracture may have to be altered in detail ; the fracture itself, instead of being single, may be rather a complex system of faults. But on two points in connexion with the theory the recent earthquake affords some welcome evidence. One is the occurrence, six days after the principal earthquake, of the after-shock in Stromboli, with its attendant increase in volcanic activity. The other is that the chief seismic focus was situated in part beneath the Straits of Messina, thus forming a junction between the seismic zones of Calabria and Sicily. Though it may have served no other useful purpose, the Messina earthquake has, in this way, supplied a link that was missing in the chain of evidence, and at the same time removed a forcible objection to Professor Suess' theory.
· The Face of the Earth (translated by Hertha B. C. Sollas), vol. i. pp. 82–86,
(A SKETCH FROM LIFE)
OLD Mrs. Jones of Typycae was in a bad temper; and 'sufficient of reason there was for it,' as she herself remarked. A month ago, at the May 'hiring' in Llan Austin, she had engaged a girl to assist her in her multifarious duties on the farm and in the house. Not without misgivings had she concluded a bargain of six months on either side, for the girl was entirely unknown to her and was moreover of very uncouth appearance; but the busy time was coming, help was imperative and girls were difficult to get, so the bargain was struck -and Mrs. Jones had been continually regretting it ever since. The girl was a savage, she declared, a perfect savage in looks, in manners, in habits, in everything. She worked not badly it was true well and cheerfully, a less exacting mistress might have said-but she was wild and mannerless as a young mountain colt, and as full of tricks. Oply a month had she been at Tynycae, yet countless already had been her misdemeanours, and, what was worse, she seemed quite indifferent to scoldings, receiving them in fact in a manner that bordered on defiance. Yet old Mrs. Jones was not a person to be easily defied. She was a gaunt old woman with a harsh unlovely visage and a cold stern eye. Of a similar nature were her views of life. Pleasure or merrymaking she abhorred, seldom did she permit herself the relaxation of an occasional neighbourly gossip, and even buryings' were distasteful to her. Work was the object of her existence, the little farm the joy of her life; she was clever and capable in her management of it, and to keep it going and make it pay she toiled early and late, sparing neither herself nor her subordinates.
Little would any one who looked upon the deeply-lined old face or into the hard eyes have guessed that in the far-off days of her youth Megan Griffiths, as she was then called, had been noted for the beauty of her face and the softness of her glance. Fatal gifts these for one of her class, and, as too often is the case, they brought her only shame and sorrow.
But that was long, long ago; she had struggled through with it, lived down the shame fought and overcome the sorrow.
The man VOL. LXV--No. 384 321