On the Nature of Things (De Rerum Natura)

Since the first-beginnings of things cannot be seen by the eyes, take moreover this list of bodies which you must yourself admit are in the number of things and cannot be seen.
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First of all, the force of the wind, when aroused, beats upon the harbors, whelms huge ships, and scatters clouds. Sometimes, in a swift whirling eddy, it scours the plains, strews them with large trees, and scourges the mountain summits with forest-rending blasts: so fiercely does the wind rave with a shrill howling and rage with a threatening roar. Winds, therefore, are sure enough unseen bodies original: "corpora caeca" which sweep the seas, the lands, and the very clouds of heaven, tormenting them and catching them up in sudden whirls. On they stream and spread destruction abroad in just the same way as the soft, liquid nature of water when it is borne along in an overflowing stream. A great downfall of water from the high hills augments it with copious rains, flinging together fragments of forests and entire trees; nor can strong bridges sustain the sudden force of the coming water.
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In such wise, turbid with much rain, the river dashes upon the piers with mighty strength. With a loud noise, the water makes havoc, rolls huge stones under its eddies, and throws down whatever opposes its waves. In this way, then, must the blasts of wind also be borne.
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