1844.] Memoir on Indian Earthquakes. 979 



perature, frequently very heavy rain, accompanied by storms and 

 changes of wind with occasionally a misty and foggy state of the 

 atmosphere. 



6. Electric Phenomena accompanying shocks. 



These have been observed but rarely in this country, a few in- 

 stances however are recorded. During the earthquake of the 7th 

 September 1842, at the moment of its occurrence, sensations precisely 

 similar to those accompanying an electric shock, were experienced by 

 an observer at Mussoorie in the Himalayas, as noted in detail in the 

 register for 1842. During the shock of the 11th of November, of 

 the same year, a peculiar brightness was observed on the waters 

 of the Hoogly which was exactly contemporaneous with the shock, 

 and on closing round the Southampton communicated to that vessel 

 " a general and severe tremor as if a taut cable was grinding under the 

 keel, or that a sudden squall had struck the ship/' It was observed 

 that this brightness could not possibly be the reflected light of the 

 moon and the possibility suggests itself that it may have been a dis- 

 play of electric light. An interesting fact is noted among the Pore- 

 bunder observations on the great Scinde earthquake of June 1819, 

 under date the 24th of that month ; after a severe shock accompanied 

 by much rain, it is noted " Immediately after it observed a long nar- 

 row black cloud, running west and east, or quite the contrary way 

 to what I am accustomed to see a line of such cloud extend : it ap- 

 peared stationary for half an hour, during which time there were con- 

 stant tremors in the earth." It is possible that these tremors may have 

 been an effect of what has been called " the return stroke" or the pas- 

 sage of electric matter from the surcharged earth to the clouds, a not 

 unusual phenomenon. During the month of April 1762, when the 

 great Chittagong earthquake occurred, it is remarked by the Reverend 

 Mr. Hirst, that " there was much thunder and lightning in this 

 month." Similarly during the shock of the 29th October 1800, 

 the incessant thunder and vivid lightning are specially remarked; 

 it would therefore appear that severe shocks of earthquakes are fre- 

 quently accompanied by electric phenomena, and although the facts 

 may not be sufficiently determinate to enable us to say that such 



