226 Earthquakes in Sicily. 



eiently strong to put in motion the pendulum of a small 

 clock, which I had stopped that I might regulate it in the 

 morning. Its vibration from north-east to south-west showed 

 me with certainty the direction of the shock. Light ones 

 were felt on the 26th. On the 31st, at fifty-two minutes past 

 two, P. M., one was felt at Messina, moderately severe, of 

 five or six seconds duration, and undulating. Two others on 

 the 1st of April, and one at Costelbuono on the 28th. I 

 should add that they mention a slight one there on the 16th 

 of February, but they are more certain of those of the 5th 

 of March, one at one P. M., the other at three. These were 

 they, which induced the inhabitants of Naso to leave their 

 habitations and flee into the country, where they were when 

 their city was laid waste. Here the professor mentions 

 many other places, in which small shocks were felt, in July 

 and August; but as no important remarks are made, we pass 

 over them to his more interesting chapter of physical obser- 

 Tations, 



Physical Observations, 



When the people about .SItna perceived their houses be?- 

 ginning to shake, they turned their eyes towards the volcano, 

 and waited in expectation of an immediate eruption And 

 while they looked, fearful apprehensions filled their minds, 

 and they prayed that the event, be it what it would, might 

 take place at once. 



The philosopher, who observes the phenomena of nature, 

 for the sake of reducing to the same class those of an analo- 

 gous origin, and thence to deduce them from the same cause, 

 observes the link which connects earthquakes with volcanic 

 operations, and sees with the ignorant vulgar, those mighty 

 forces preparing in the subterranean furnace which are able 

 to put in motion immense masses of the solid globe, and to 

 agitate them as water is agitated by a violent wind. The 

 eruption of ^tna in 1811 was interesting from the grandeur 

 of the spectacle which it presented, and no less so, from the 

 instruction which it conveyed to the naturalist. A new open- 

 ing was made on the surface of the mountain. Explosions of 

 tremendous force preceded the emission of immense columns 

 of smoke and inflamed masses of matter, which were inces- 



