93 
SECT. XVIII. 
THE SAME SUBJECT CONTINUED; 
WITH A PARTICULAR ACCOUNT OF SOME ERUPTIONS OF MOUNT iETNA, AND 
VESUVIUS, AND THE EARTHQUAKE AT LISBON. 
.Ah ! whither now are fled 
Those dreams of greatness? Those unsolid hopes 
Of happiness? Those longings after fame? 
Those restless cares? Those busy, bustling days? 
Those gay-spent, festive nights? Those veering thoughts* 
Lost between good and ill, that shar’d thy life? 
All now are vanish'd !—VIRTUE sole survives. 
Immortal, never-failing friend of man, 
His guide to happiness on high. 
Thomson. 
We come now to another set of philosophers* who entertain the opinion, 
that the earth’s heat arises from the conflict of elements contained within her 
bosom. 
First, With regard to the heat found in deep caverns, which rises above 
that of the surrounding atmosphere, they conceive that this may proceed from 
other causes than an actual fire in the center of our globe. 
For only call to your recollection the principles composing the earth, its 
copious stores of sulphureous, metallic, bituminous, and other inflammable 
matters, which have only to meet with oxygenated water, when a decompo¬ 
sition takes place, liberating a vast quantity of free caloric. 
In Section XII. we mentioned the sentiments of Mayow respecting the 
2 A 
