978 Memoir on Indian Earthquakes, [No. 156. 



that no hurricane occurs without some volcanic action more or less 

 violent being observed, and as the whole of the chain of the Phillipines 

 from Mindanao to the northern extreme is full of active or partially 

 active centres, far more so even than Java, there seems good ground 

 for supposing some connection, but whether the volcanoes are the cause, 

 or are agitated by the effect of the atmospheric disturbance, we are 

 as yet ignorant. In the Bay of Bengal, if the tracks of most of our 

 storms be prolonged to the south-east they will all be seen to start from 

 near the yet active volcanic centre of Barren Island, and some of the 

 old ones which I have traced certainly do the same. 



" Again ; if we look at Mr. Redfield's chart of West Indian hurricanes, 

 we shall find them also mostly beginning about the volcanic Leeward 

 Islands. The neighbourhood of Bourbon and Mauritius, and the 

 Timor sea, where hurricanes seem very prevalent, are all instances 

 of this sort of relation whatever it may be, if it really exists/* 



The general question of the relation of volcanic to atmospheric dis- 

 turbances is one well worthy of investigation, and it is to be hoped 

 that observers favourably situated may not neglect opportunities of 

 collecting such information as may throw light upon its true character. 

 Circumstances are favourable for observations on this point in the 

 earthquake tract of the eastern coast of the Bay of Bengal, including 

 Chittagong, Arracan, &c. along the whole of the Malayan Archi- 

 pelago and the coast of the Persian Gulf. 



e. Mists and Fogs. The last indication of atmospheric disturbance 

 during earthquakes I have to notice, is the not unfrequent occurrence 

 of mists and fogs in connection with the shocks. Thus during the 

 earthquake of the 21st May 1842, it is noted " that for some days 

 before and after this, the sky had a white, thick, hazy appearance ;" 

 again during the Assam shock of the 4th March 1840, it was obser- 

 ved by Captain Hannay, that although " the sky was cloudless yet 

 the atmosphere was hazy." The shock of the 24th October, 1832 

 near Delhi was in like manner accompanied by haziness in the air. 



The general results under this head may now be summed up in 

 a few words. The atmospheric phenomena which have been observed 

 to accompany earthquakes in India, so generally as to suggest 

 the existence of an intimate connection between the two classes of 

 facts, are, a depressed state of the Barometer, unusually high tern- 



