The conception of nature as exhibiting sympathy with sudden turns in human affairs is one of the most fundamental instincts of poetry. To cite notable instances: it is this which accompanies with storm and whirlwind the climax to the Book of Job, and which leads Milton to make the whole universe sensible of Adam's transgression:
Earth trembl'd from her entrails, as again
In pangs, and Nature gave a second groan;
Sky lowr'd, and muttering thunder, some sad drops
Wept at completing of the mortal sin
Original.
So too the other end of the world's history has its appropriate accompaniments: 'the sun shall be darkened and the moon shall not give her light, and the stars shall be falling from heaven.' There is a vagueness of terror inseparable from these outbursts of nature, so mysterious in their causes and aims. They are actually the most mighty of forces—for human artillery is feeble beside the earthquake—yet they are invisible: the wind works its havoc without the keenest eye being able to perceive it, and the lightning is never seen till it has struck. Again, there is something weird in the feeling that the most frightful powers in the material universe are all soft things. The empty air becomes the irresistible wind; the fluid and yielding water wears down the hard and massive rock and determines the shape of the earth; impalpable fire that is blown about in every direction can be roused till it devours the solidest constructions of human skill; while the most powerful agencies of all, electricity and atomic force, are imperceptible to any of the senses and are known only by their results. This uncanny terror attaching to the union between force and softness is the inspiration of one of Homer's most unique episodes, in which the bewildered Achilles, struggling with the river-god, finds the strength and skill of the finished warrior vain against the ever-rising water, and bitterly feels the violation of the natural order—
That strong might fall by strong, where now weak water's luxury
Must make my death blush.
i. iii; ii. ii, &c.