On the Nature of the Universe (Oxford World’s Classics) (50 page)

So everything is full of winds and fires

And thunderclaps and lightning everywhere.

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For indeed I have shown above that hollow clouds

Must contain very many seeds of fire

And must receive many from the sun’s hot rays.

Therefore, when the same wind that has driven them

Into one place together, has squeezed out

Many seeds of fires, and in so doing itself

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Has intermingled with the fire, the whirlwind

Finds its way in, whirls round in the narrow space

And in the hot furnace sharpens the thunderbolt.

For the wind is kindled in two ways: by the heat

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Of its own motion, and by contact with the fire.

Next when the wind has reached a mighty heat

And the strong impulse of the fire has entered,

The thunderbolt, now as it were ripe, cleaves through

The cloud by a sudden blow, and the heat, shot out,

Lights all the place beneath with flashing flames.

A deep roar follows, such that the vault of heaven

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Seems to be sundered apart and falling on us.

A violent tremor now assails the earth

And murmurs roll about the sky; for then

Almost the whole storm quivers with the shock

And roars and crashes. Rain then, heavy and full,

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Follows the shock, so that the whole ether

Seems to be turned to rain, and teeming down

Recalls again the universal Flood.

So much the bursting cloud and raging wind

Pour out when the sound flies from the flaming stroke.

Sometimes also a powerful wind outside

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Falls on a cloud pregnant with a ripe thunderbolt.

It bursts it, and at once that fiery whirlwind falls

Which we name thunderbolt in our native tongue.

And this can strike in various directions,

Depending on the impulse given to it.

Sometimes also a wind that has no fire

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Kindles nevertheless on its long flight through space;

It loses on its course a number of bodies

Too large to keep up with it through the air,

And scrapes together from the air itself

And carries with it other tiny bodies

That mixed with it make fire as it flies,

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In much the same way as a leaden bullet

Often grows hot in flight, when throwing off

The seeds of cold it catches fire in the air.

Sometimes also a blow produces fire,

When a cold wind launched without fire has struck.

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Doubtless because when it has struck a violent blow

Elements of heat can flow together

Both from the wind itself and at the same time

From the object receiving the blow, as fire flies out

When stone is struck with iron, and the fire comes

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No whit the less because the iron is cold.

So also a thing must take fire from a thunderbolt

If it be fit and suitable for flame.

And no wind ever can be utterly

And absolutely cold, if from above

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So powerful a force has driven it.

If it has not caught fire on its course,

When it arrives it must be warm and mixed with heat.

The speed and violent stroke of thunderbolts

And the swift fall with which they cleave the sky

Have this as their cause: a force within the clouds,

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First everywhere aroused, accumulating

Takes on a mighty energy of movement.

Then when the cloud cannot hold the growing impetus

The force explodes, and flies with wondrous speed

Like missiles hurled from powerful catapults.

Moreover, it consists of elements

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Both small and smooth, so that it is not easy

For anything to counter such a substance.

For it flies in between and penetrates

Through narrow passages, therefore few obstacles

Can check it or delay it as it comes;

And this is why it falls with flight so swift.

Again, while all weights naturally possess

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A downward momentum, when a blow is added

The speed is doubled, and the first impulse

Grows heavier, so that with greater speed and strength

It shatters whatever delays it on its course.

Again, the momentum of its lengthy flight

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Must give it ever-growing speed, increasing

As it falls, and this augments its mighty power

And strengthens the blow. It causes all its atoms

To move straight forward to a single point

And throws them together as they flow into that path.

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It may perhaps draw from the air itself

In the course of its flight certain particles

Which by their impact set its speed ablaze.

It passes through things without harming them,

And leaves many things intact after its transit,

Because the fluid fire goes through the pores.

And many it transfixes, when its atoms

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Strike upon other atoms that form a joint.

It readily dissolves bronze and in an instant

Melts gold, because the atoms of which it is made

Are small and smooth and therefore easily

Make their way in, and having got in, at once

Untie all knots and loosen every bond.

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In autumn thunder shakes the house of heaven,

Studded with shining stars, more often, and shakes the earth,

And also when springtime opens with its flowers.

For in the cold fires are few, and in the heat

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The winds fail and clouds are not so thick.

So when the season stands between the two

Then all the various causes of thunderbolts

Combine and flow together in the sky.

For then the year’s rough straits mix cold and heat

(And a cloud needs both to make a thunderbolt),

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So discord comes and with a mighty tumult

And fire and wind the heavens rage and swell.

For the first time of heat is the last of cold,

That is the spring. So battle must be joined

With fray embroiled between things unalike.

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And when the last heat mixed with early cold

Comes round, to which we give the name of autumn,

Here also bitter winter fights with summer.

Therefore these must be named the straits of the year,

And it’s no wonder if these seasons produce

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Thunderbolts in abundance, and a whirling storm

Forms in the sky, since war everywhere

Rocks it on two fronts, on the one side flames

And on the other wind and water mixed.

Thus the true nature of the thunderbolt

Can now be understood, and how it works;

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Not by unrolling scrolls of Tuscan charms

To search in vain the hidden minds of gods

And ask them whence the flying fire has come

Or to what other quarter of the sky

It went, and in what way it penetrated

Through walls of buildings, and having worked its will

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Inside, made its way out again, or ask what harm

The stroke of a thunderbolt from heaven can do.

If Jupiter and other gods, my friend,

Shake with appalling din the realms of heaven,

And shoot their fire where each one wants to aim,

Why do they not arrange that when a man

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Is guilty of some abominable crime

He’s struck, and from his breast transfixed breathes out

Hot flames, a bitter lesson to mankind?

Why is a man of conscience free from stain

Engulfed in flames, all innocent, suddenly

Seized by a fiery whirlwind from the sky?

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Why do they waste their pains shooting at deserts?

Or are they merely practising their aim

And strengthening their muscles? Why do they allow

The Father’s bolt to be blunted on the ground?

Why does he allow this himself, and not keep it

For his enemies? And why does Jupiter

Never when the sky is cloudless everywhere

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Launch bolts upon the earth and sound his thunder?

Or does he wait until the clouds have formed

And then himself descend down into them

To aim his weapon from a shorter range?

What is his object when he strikes the sea?

Has he some grudge against the waves and all