72 ANNUAL RECORD OF SCIENCE AND INDUSTRY, 



EARTHQUAKES IN ITALY. 



The supplement to the Meteor olo g la Itallana for 1874 con- 

 tains a memoir by Serpieri on the earthquake of the 12th of 

 March, 1873, concerning which the veteran Alexis Perry says 

 that it has laid the foundation for connectino; tocrether in a 

 philosophical manner all the seismic and volcanic phenomena 

 of Italy; and crowning as it does the well-known labors 

 through so many years of Serpieri, it forms a fitting memoir 

 with which to begin the Bulletin of Vulcanology in Italy. 

 In this memoir the author begins by the study of the signifi- 

 cation of the records of earthquakes made by self-recording 

 pendulums. Self-registering seismographs have been invented 

 by numerous Italians, to say nothing of those of Hopkins, 

 Forbes, Mallet, and other foreigners. The most successful of 

 the Italian investigators in this respect would seem to have 

 been Bertelli, who, with De Rossi, has paid attention to the 

 study of the minute, almost microscopic movements of the pen- 

 dulum whicli precede severe earthquakes, and which have been 

 studied by the help of ninety-four accurate observations at 

 as many diflTerent stations as they were reported to Serpieri. 

 These were very equally distributed on all sides of the cen- 

 tral disturbance, and show tliat the original shock was of the 

 nature of a line of fracture extendinsj from near Florence 

 southeastward about fifty miles, within which region it seems 

 possible that several fractures may have followed each other 

 in rapid succession over neighboring portions of territory. 

 A comparison of the observations made on the 12th of Marcli, 

 1873, with those made on the 6th of December, 1874, and the 

 24th of February, 1875, as calculated by De Rossi in his anal- 

 ysis of the three great Italian earthquakes, show that in all 

 these cases these transverse fractures in the terrestrial crust 

 are succeeded by transverse vibrations in the same. Supple- 

 mento alia Meteorologia Italiana^ Rome^ 1875, 56. 



NOCTUENAL RADIATION. 



Mr. Barham, in communicating to the Royal Institution of 

 Cornwall some remarks on the surface temperature of the 

 earth, states that the common estimate of the greatest cold 

 durino; the nisjht is derived from the record of a thermometer 

 hanging up on a stand, or under a shed or other shelter; yet 



