226 Earthquakes in Sicily. 
ciently strong to put in motion the pendulum of a small 
lock, 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 3ist, 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 Ist 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 
habiiations 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- 
vations, 
Physical Observations. 
When the people about tna perceived their houses be- 
ginning to shake, they turned their eyes towards the velcano, 
and waited in expectation of an immediate eruption. 
while they looked, fearful apprehensions filled their minds, 
aud 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 yulgar, 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 
snstruction 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 mces- 
