First of all, since the substance of the earth, Moisture, and the light breathings of the air, And burning heats, of which this sum of things Is seen to be composed, have all been formed Of a body that was born and that will die, Of such a body must we likewise deem That the whole nature of the world was made. For things whose parts and members we see formed Of a body that had birth and shapes that die, These we perceive are themselves always mortal, And likewise have been born. Since then we see That the chief parts and members of the world Decay and are reborn, it is no less certain That once for heaven and earth there was a time Of origin, and will be of destruction. Herein lest you should think that without proof I have seized this vantage, in that I have assumed Earth and fire to be mortal, and have not doubted That moisture and air perish, but maintained That these too are reborn and grow afresh, Consider first how no small part of the earth Ceaselessly baked by the sun’s rays and trampled By innumerable feet, gives off a mist And flying clouds of dust, which the strong winds Disperse through the whole atmosphere. Part too Of the earth’s soil is turned to swamp by rains, While scouring rivers gnaw their banks away. Furthermore whatsoever goes to augment Some other thing, is in its turn restored; And since beyond all doubt the all-mother Earth Is seen to be no less the general tomb, You thus may see how she is ever lessened, Yet with new growth increases evermore. Next, that the sea, the rivers and the springs Are always amply fed by new supplies Of moisture oozing up perennially, It needs no words to explain. The vast down-flow Of waters from all sides is proof of this. But as the water that is uppermost Is always taken away, it comes to pass That on the whole there is no overflow; Partly because strong winds, sweeping the seas, Diminish them, and the sun in heaven unweaves Their fabric with his rays; partly because The water is distributed below Throughout all lands. For the salt is strained off, And the pure fluid matter, oozing back, Gathers together at the river-heads, Thence in fresh current streams over the land, Wherever it finds a channel ready scooped To carry down its waves with liquid foot. Now must I speak of air, which every hour Is changed through its whole body in countless ways. For always whatsoever flows from things Is all borne into the vast sea of air: And if it were not in its turn to give Particles back to things, recruiting them As they dissolve, all would have been long since Disintegrated, and so changed to air. Therefore it never ceases to be born Out of things, and to pass back into things, Since, as we know, all are in constant flux.