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THE GEOLOGIST. 



It was learnt shortly afterwards that a most violent earthquake had 

 ravaged, on the night which separated the 16th and 17th of December, 

 the greater portion of the two Sicilies, especially the town of Salerno, 

 Potenza, and Pola. Many thousands of the population perished in the 

 Basilicata and neighbouring provinces, where the phenomena appear to 

 have been concentrated, l^aples itself experienced three violent shocks, 

 which, however, were fortunately unattended by loss of life. Other 

 convulsive movements of the earth were felt in ISTaples on the 19th, 

 20th, and 23rd of the same month. The inhabitants, much terrified, 

 hoped, and prayed for an eruption of Vesuvius. The earthquake of the 

 1 7th December produced a certain effect on the south parts of Germany. 

 Bavaria and Wurtemburg likewise experienced its influence ; and on the 

 20th December, at half-past five o'clock in the morning, violent shocks 

 were felt at Agram, in Crotia. The undulations of the ground took a 

 direction from the south-east to the north-west, and the shaking of the 

 earth lasted about three hours and a half. 



During the early days of last January, the amplitude of oscillation in 

 the magnetic needle of the Brussels Observatory evinced considerable 

 irregularity, especially on the 5th, 6th, and 7th of that month. But on 

 the 9th the needle was, moreover, suddenly displaced at each oscillation. 

 The papers made known shortly afterwards that an earthquake had 

 taken place on the 8th and 9th of January, at Yarna. 



These data evidently tend to prove that a certain relation exists 

 between the phenomenon of earthquakes and terrestrial magnetism.-'' 

 But this relation of which we speak, to what extent is it established ? 

 Can we admit, with Mr. Evan Hopkins, that terrestrial magnetism is the 

 great and sole agent of nature by which all geological changes have 

 been, or are, accomplished r Certainly not. This author's hypothesis 

 is, however, extremely curious. "We are indebted for an abstract of it 

 to an accomplished geologist, Miss Catherine J. B. Taylor, and we are 

 thus enabled to let our readers judge for themselves, Mr. E. Hopkins 

 endeavours to demonstrate that the slow operation of that power which 

 wc call terrestrial magnetism accounts for all the changes observed on 

 the surface of the earth, in the structure, combinations, and relations of 



* Whilst writing the above, the following passage of Humbolt's is irresistibly 

 oallod to mind : — " When the needle, by a sudden disturbance in its horary course, 

 indicates the presence of a magnetic storm, we are still unfortunately ignorant 

 whether the seat of the disturbing cause is to be sought in the earth itself or in 

 the upper regions of the atmosphere." {Cosmos, vol. /.)— T.L.P. 



