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Show CHAPTER XXIV. k · c 1 bria February or, th ' 1783-Shocks continued to th.e end of Earthqua e m a a ' . . E t t f the area convulsed-Geologtcal struc- 1786 Authonbes- x en o the year - . f taining changes of relative level even .1. t . t Difficulty o ascer ture of the ulS nc - h t Messina-Shift or fault in the t s bsidence of t e quay a . on the sea-coas -· u M t in the stones of two obchsks-f T rranuova- ovemen Round Tower 0 . ed clos.m g of fi ssures -Cause of this phenomenon-Large Alternate opemng an . . f erns and fissures-Gradual closing 1 h d Dtmens10ns o new cav edifices engu P e -d' of detachec1 masses m. to the air-Lamlslips-Buildings in of rents-Boun mg . F rmation of fifty new lakcs-Cur- .1 f . to great d1stances- o . transporteu en no, d h 11 s in alluvial plains-Fall of chffs d s n funnel-shape 0 ow ' rents of mu - mat Shore near S .11 • . undated-State of Stromboli and Cl a m along the sea-co as - Ill t ·t' 0 affordetl by this earthquake of the Etna during the shocks- us ra 1 n mode in which valleys are formed. k which have occurred in different OF the numerous ear~q~a e:he last hundred years, that of parts of the glob~, ~rmgl e of which the geologist can Calabria, in 1783, IS t e. on y otnntial account as to enable him 'd h such a circums a . bl f be sal to av~ han es which this cause IS capa co fully to appreciate the fc g The shocks began in February, producing in the lapse o agfs.£ years to the end of 1786. 1783, and lasted for. near! o~rl nee 'nor in the extent of . d t' n nor m VIO e ' Neither m ura 10 ' h' ulsion remarkable, when con- . d was t 1s conv . 1 d · tern tory move ' . d · th r countnes, bot l urmg trasted w·i th many experience m . 0 e the alterations w1 u· c h t ntury . nor were d the last and presen ce . '1 ] of hill and valley, land an · d · the relative eve t it occasiOne m ff' t d by some subterranean movemen s sea so great as those e ec e . The importance of the in S' outh Amen·c a, m· . our ow. n timf es. the circumstance, 1 t t la earthquake m. ques t on arises rom d f . I . h . 't d both during an a ter 1 t hit erto v1si e , Calabria is the on y spo . sufficient leisure, zea 1' an(1 . b men possessmg d d :b the convulswns, ~ bl them to collect an escn c scientific informatiOn, t? ;n~ac~s which throw light on geolowith accuracy the physica gical questi·O ns. l .'f s Vivenzio, physi·c i·a n to the Among the llUmerous aut 10ll Ie ' EARTHQUAKE IN CALABRIA, A,D. 1783. 413 King of Naples, transmitted to the court a regular statement of his observations during the continuance of the shocks; and his narrative is drawn up with care and clearness*. Francesco Antonio Grimaldi, then secretary of war, visited the different provinces at the king's command, and published a most detailed description of the permanent changes in the surfacet. He measured the length, breadth, and depth of the different :fissures and gulphs which opened, and ascertained their number in many provinces. His comments, moreover, on the reports of the inhabitants, and his explanations of their relations, are judicious and instructive. Pignataro, a physician residing at Monteleone, a town placed in the very centre of the convulsions, kept a register of the shocks, distinguishing them into four classes, according to their degree of violence. From his work, it appears that, in the year 1783, the number was nine hundred and forty-nine, of which five hundred and one were shocks of the first ~degree of force; and in the following year there were one hundred and fifty-one, of which ninety-eight were of the first magnitude. Count Ippolito, also, and many others, wrote descriptions of the earthquake; and the Royal Academy of Naples, not satisfied with these and other observations, sent a deputation from their own body into Calabria, before the shocks had ceased, who were accompanied by artists instructed to illustrate by drawings the physical changes of the district, and the state of ruined towns and edifices. U nfortunately these artists were not very successful in their representations of the condition of the country, particularly when they attempted to express, on a large scale, the extmordinary revolutions which many of the great and minor rivercourses underwent. But many of the plates published by the Academy are valuable; and we shall frequently avail ourselves of them to illustrate the facts about to be described t· In ad. clition to these Neapolitan sources of information, our countryman, Sir William Hamilton, surveyed the district, not without some personal risk, before the shocks had ceased; and his sketch, published in the Philosophical Transactions, supplies many facts that would otherwise have been lost. He has explained * Istoria do' Tre~uoti della Calabria, del 1783. t Descriz. de' Tremuoti Accad. neUe Calabria nel 1783. Napoli, 1784. ~ Istoria de' Fenomeni del Tremoto, &c. nell' an. 1783, posta in lucc dalla Real. Accad., &c., di Nap. Napoli, 1784, fol. |