Page:Great Neapolitan Earthquake of 1857 Vol 2.djvu/220

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AND AFTER THE GREAT ONE OF DECEMBER.
159


Date. Time (Frankish). Occurrence of Shock
1858. March 8 At 12 to 1 midnight At Salerno. All the shocks between the 7th and 8th were felt at Potenza, at Tramutola—which they greatly further injured—at Montemurro, at Vibonati, and at Sapri.
" 13 .. At Rodi, province of Capitanata.
" 17 .. At Potenza, and elsewhere in the province of Capitanata, the earth was said to have trembled almost incessantly.
" 23 10 A.M. and 2 P.M. At Potenza, the first slight—three or four at the latter hour more severe.
" 23 2 P.M. At La Sala (Val di Diano), four shocks, all harmless.
April 8 5.15. & 7.30 A.M. At Palmi, sharp subsultatory shocks.
" 10 8, 9, and 10 A.M. At Reggio, three shocks.

My record does not extend beyond the last given date, but letters from private friends resident in the Neapolitan kingdom inform me, that such occasional shocks continued sporadically to be reported, even up to the month of May, in 1859. Those given, sufficiently indicate, that which is the general fact, in all earthquake regions, that, when once the state of seismical repose is powerfully broken, it is only resumed through a long-continued succession of these abortive and decreasing transitory commotions. The general tendency of the preceding table is also to indicate, that after the great shock of December, 1857, some subordinate centre or centres of activity, further south than the focus of the first, came on to a sort of expiring activity. To this sort of fact, apparently, Humboldt points in 'Cosmos,' when he says, that in South America, the tendency of earthquake activity, is continually to enlarge its circle of action round a given focus.