De Rerum Natura

As we behold the clouds grow thick on high

And smirch the serene vision of the world,

Stroking the air with motions. For oft are seen

The giants' faces flying far along

And trailing a spread of shadow; and at times

The mighty mountains and mountain-sundered rocks

Going before and crossing on the sun,

Whereafter a monstrous beast dragging amain

And leading in the other thunderheads.

Now [hear] how easy and how swift they be

Engendered, and perpetually flow off

From things and gliding pass away....

. . . . . .

For ever every outside streams away

From off all objects, since discharge they may;

And when this outside reaches other things,

As chiefly glass, it passes through; but where

It reaches the rough rocks or stuff of wood,

There 'tis so rent that it cannot give back

An image. But when gleaming objects dense,

As chiefly mirrors, have been set before it,

Nothing of this sort happens. For it can't

Go, as through glass, nor yet be rent- its safety,

By virtue of that smoothness, being sure.

'Tis therefore that from them the images

Stream back to us; and howso suddenly

Thou place, at any instant, anything

Before a mirror, there an image shows;

Proving that ever from a body's surface

Flow off thin textures and thin shapes of things.

Thus many images in little time

Are gendered; so their origin is named

Rightly a speedy. And even as the sun

Must send below, in little time, to earth

So many beams to keep all things so full

Of light incessant; thus, on grounds the same,

From things there must be borne, in many modes,

To every quarter round, upon the moment,

The many images of things; because

Unto whatever face of things we turn

The mirror, things of form and hue the same

Respond. Besides, though but a moment since

Serenest was the weather of the sky,

So fiercely sudden is it foully thick

That ye might think that round about all murk

Had parted forth from Acheron and filled

The mighty vaults of sky- so grievously,

As gathers thus the storm-clouds' gruesome night,

Do faces of black horror hang on high-

Of which how small a part an image is

There's none to tell or reckon out in words.

Now come; with what swift motion they are borne,

These images, and what the speed assigned

To them across the breezes swimming on-

So that o'er lengths of space a little hour

Alone is wasted, toward whatever region

Each with its divers impulse tends- I'll tell

In verses sweeter than they many are;

Even as the swan's slight note is better far

Than that dispersed clamour of the cranes

Among the southwind's aery clouds. And first,

One oft may see that objects which are light

And made of tiny bodies are the swift;

In which class is the sun's light and his heat,

Since made from small primordial elements

Which, as it were, are forward knocked along

And through the interspaces of the air

To pass delay not, urged by blows behind;

For light by light is instantly supplied

And gleam by following gleam is spurred and driven.

Thus likewise must the images have power

Through unimaginable space to speed

Within a point of time,- first, since a cause

Exceeding small there is, which at their back

Far forward drives them and propels, where, too,

They're carried with such winged lightness on;

And, secondly, since furnished, when sent off,

With texture of such rareness that they can

Through objects whatsoever penetrate

And ooze, as 'twere, through intervening air.

Besides, if those fine particles of things

Which from so deep within are sent abroad,

As light and heat of sun, are seen to glide

And spread themselves through all the space of heaven

Upon one instant of the day, and fly

O'er sea and lands and flood the heaven, what then

Of those which on the outside stand prepared,

When they're hurled off with not a thing to check

Their going out? Dost thou not see indeed

How swifter and how farther must they go

And speed through manifold the length of space

In time the same that from the sun the rays

O'erspread the heaven? This also seems to be

Example chief and true with what swift speed

The images of things are borne about:

That soon as ever under open skies

Is spread the shining water, all at once,

If stars be out in heaven, upgleam from earth,

Serene and radiant in the water there,

The constellations of the universe-