O'Beilly — On Localities marked by Earthquakes. 505 



l^ow, assuming as admitted, Pirstly, the connexion iDetween vol- 

 canic action and earthquakes ; Secondly, the connexion between 

 volcanic action and coast-line directions ; and Thirdly, the connexion 

 between coast-line directions and main systems of jointing, there 

 should be a connexion existing between these coast-line directions and 

 localities wherein earthquake action manifests itself. 



If, therefore, the earthquake records for a series of years be taken, 

 and the localities mentioned be noted on a map ; if, furthermore, the 

 coast-line directions traced by me d priori on the globe be also laid 

 down on this map, there should (if my theory be well founded) be 

 apparent some relation between the earthquake localities and these 

 directions or their correlated lines. 



It is this test, applied to the map of Europe, which I now submit 

 for consideration, carried out by marking the earthquake localities 

 noted in the records of Mallet, Perrey, and Puchs down to 1880. 



In thus marking the localities mentioned, I was unable to distinguish 

 between intensity and frequency of occurrence, except by hatching 

 districts over which shocks have extended, and rehatching or cross- 

 hatching, to mark the reoccurrence of the earthquake under the same 

 conditions. For single localities, however, a simple round or small 

 circle in red indicates that they have been cited as having suffered at 

 least one shock. 



!N"o such map has been before prepared, and the present one must 

 be judged rather as an essay than as a complete work. If intensity and 

 frequency could be represented on such a map, very interesting rela- 

 tions would certainly be established thereby. If, moreover, such map- 

 ping could be done on a globe, still more remarkable results might be 

 expected to follow. 



An examination of the map shows that as the localities are multi- 

 plied, so does their tendency to develop into certain lines become more 

 marked ; and considering, on the one hand, the meagreness and incom- 

 pleteness of these records down to the middle of the last century, or 

 commencement of the present, and on the other the shortness of historic 

 time as regards the development of geognostical phenomena, the results 

 manifested by the map must be considered as distinctly pointing to a 

 law of connexion between coast-line directions and certain earthquake 

 districts in Europe. 



Of the localities lying in Europe and around the basin of the Medi- 

 terranean, which have been and continue to be marked by frequent 

 and violent earthquakes, the following are the principal : — 



Italy and Sicily. 



The Adriatic coast-lines. 



Greece and the adjacent islands. 



The triangular space bounded on the west by the Rhone, on the 

 south-east by the Mediterranean coast-line from Marseilles to Genoa 

 and the prolongation thereof from Genoa to Trieste, and on the north- 

 east by a line extending from the Vosges to the neighbourhood of 



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