And stalwart flint and strength of solid iron,
And brazen bars, which, budging hard in locks,
Do grate and scream. But what are liquid, formed
Of fluid body, they indeed must be
Of elements more smooth and round--because
Their globules severally will not cohere:
To suck the poppy-seeds from palm of hand
Is quite as easy as drinking water down,
And they, once struck, roll like unto the same.
But that thou seest among the things that flow
Some bitter, as the brine of ocean is,
Is not the least a marvel...
For since 'tis fluid, smooth its atoms are
And round, with painful rough ones mixed therein;
Yet need not these be held together hooked:
In fact, though rough, they're globular besides,
Able at once to roll, and rasp the sense.
And that the more thou mayst believe me here,
That with smooth elements are mixed the rough
(Whence Neptune's salt astringent body comes),
There is a means to separate the twain,
And thereupon dividedly to see
How the sweet water, after filtering through
So often underground, flows freshened forth
Into some hollow; for it leaves above
The primal germs of nauseating brine,
Since cling the rough more readily in earth.
Lastly, whatso thou markest to disperse
Upon the instant--smoke, and cloud, and flame--
Must not (even though not all of smooth and round)
Be yet co-linked with atoms intertwined,
That thus they can, without together cleaving,
So pierce our body and so bore the rocks.
Whatever we see...
Given to senses, that thou must perceive
They're not from linked but pointed elements.

The which now having taught, I will go on
To bind thereto a fact to this allied
And drawing from this its proof: these primal germs
Vary, yet only with finite tale of shapes.
For were these shapes quite infinite, some seeds
Would have a body of infinite increase.
For in one seed, in one small frame of any,
The shapes can't vary from one another much.
Assume, we'll say, that of three minim parts
Consist the primal bodies, or add a few:
When, now, by placing all these parts of one
At top and bottom, changing lefts and rights,
Thou hast with every kind of shift found out
What the aspect of shape of its whole body
Each new arrangement gives, for what remains,