The Decline and Fall of the Roman Empire · ¶152

II. The near approach of a comet may injure or destroy the globe which we inhabit; but the changes on its surface have been hitherto produced by the action of volcanoes and earthquakes. The nature of the soil may indicate the countries most exposed to these formidable concussions, since they are caused by subterraneous fires, and such fires are kindled by the union and fermentation of iron and sulphur. But their times and effects appear to lie beyond the reach of human curiosity; and the philosopher will discreetly abstain from the prediction of earthquakes, till he has counted the drops of water that silently filtrate on the inflammable mineral, and measured the caverns which increase by resistance the explosion of the imprisoned air. Without assigning the cause, history will distinguish the periods in which these calamitous events have been rare or frequent, and will observe, that…

Edward Gibbon · Project Gutenberg #734 (Milman edition) — public domain
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