22 ^ On Volcanos and Earthquakes. 



Portugal, France, Hamburg, the coast of England, and even 

 to the north of Scotland. However, a fact observed b)' 

 Captain Affleck, of the Advice man-of-war, then at Antigua, 

 and recorded in the Philoso. Transactions, vol. 49, surpasses 

 in wonder even all this : 



" On the first of November last, you had a remarkable flux 

 and reflux of the sea at Portsmouth, and other parts of the coast, 

 which was agitated in like manner, at the same time, on the 

 coast of America, and all these islands." 



If by the words "same time" is meant the same hour, it 

 is in fact three hours later, on account of the difference of 

 longitude, and the distance between the point of explosion 

 across the Atlantic to the Antilles, being about four thousand 

 miles, and will give a velocity of two thousand and forty feet 

 in a second of time. This velocity cannot be that of a wave 

 of water ; it must be, it can be, but a velocity of percussion 

 in an elastic fluid or gas of a greater density than atmosphe- 

 ric air. This fact, and similar ones, will enable us one day 

 to give not only a mathematical demonstration of the exist- 

 once of such a fluid under the sea, but also to calculate ex- 

 actly its density. 



Let us proceed in our investigation. 



Earthquake in Calabria, 1G38. 



In Goldsmith's History of the Earth, is an account of that 

 great convulsion of nature, translated from the celebrated 

 Father Kircher, from which we extract the two following 

 observations : 



" The Gulph of Charybdis, which we approached, seemed 

 whirled round in such a manner as to form a vast hollow, verg- 

 ing to a point in the centre." 



And afterwards : 



" The sea itself seemed to wear a very unusual appearance. 

 Those who have seen a lake in a violent shower of rain, covered 

 all over with bubbles, will conceive some idea of its agitation; 

 my surprise was still increased by the calmness and serenity of 

 the weather; not a breeze, not a cloud " 



The rushing of the sea into a subterranean abyss cannot 

 be better demonstrated than by the first observation, and the 

 ejection of gases through its water, than by the second. 



