290 Mr D. Milne 07i Earthquake-Shocks in Great Britain^ 



It may now, therefore, be held as conclusively established, 

 that an intimate connection exists between the state of the at- 

 mosphere and the frequency of earthquake-shocks. What the 

 nature, and, still more, what may be the cause of that con- 

 nection, it would be premature to inquire, before all the phe- 

 nomena which bear on the subject have been explained and con- 

 sidered. Some of these phenomena will now be mentioned. 



9. Whatever may be the time of the year in which shocks 

 occur in this country, the weather has been at or about the 

 time of their occurrence generally warm, and what is termed 

 ctose^ or suttry. 



During the winter of 1749-50, which was followed by an 

 unusual number of earthquakes in the south of England, the 

 weather was remarked as *' extraordinary " for warmth. *' The 

 warmth on some days, especially on the 13th February, was 

 greater than in the previous June." On the 8th February, 

 the day of the shock, the air is represented as " very hazy and 

 warm at the time.""* 



It is stated that, at Plymouth, from the beginning of June 

 to the 15th July 1757, when an earthquake occurred along the 

 south-west coasts of England, the weather was very warm, dry, 

 and occasionally excessively hot. On the 11th, 12th, and 13th 

 July, Fahr. thermometer in the shade was not less than 87°, 

 at three p.m. ; and on the 12th, it was 88°. In London, the 

 thermometer, between the 10th and 15th July, was as high as 

 85° (viz. on the 14th), and not lower than 80°.t 



Under date August 1786, it is noted, that, *< on the preced- 

 ing evening, the weather was so close and sultry, as to render 

 breathing oppressive." 



At the time of the Chichester earthquake in September 

 1833, " the air was very sultry, warm, and still." In the one 

 which occurred at the same place, on 23d January 1834, it is 



* Phil©8. Trans, for 1700. 



t Ibid, for 1757, p. 428. 



