Lucretius, De Rerum Natura
William Ellery Leonard, Ed.

     And, now, the speed and stroke of thunderbolt
Is so tremendous, and with glide so swift
Those thunderbolts rush on and down, because
Their roused force itself collects itself
First always in the clouds, and then prepares
For the huge effort of their going-forth;
Next, when the cloud no longer can retain
The increment of their fierce impetus,
Their force is pressed out, and therefore flies
With impetus so wondrous, like to shots
Hurled from the powerful Roman catapults.
Note, too, this force consists of elements
Both small and smooth, nor is there aught that can
With ease resist such nature. For it darts
Between and enters through the pores of things;
And so it never falters in delay
Despite innumerable collisions, but
Flies shooting onward with a swift elan.
Next, since by nature always every weight
Bears downward, doubled is the swiftness then
And that elan is still more wild and dread,
When, verily, to weight are added blows,
So that more madly and more fiercely then
The thunderbolt shakes into shivers all
That blocks its path, following on its way.
Then, too, because it comes along, along
With one continuing elan, it must
Take on velocity anew, anew,
Which still increases as it goes, and ever
Augments the bolt's vast powers and to the blow
Gives larger vigour; for it forces all,
All of the thunder's seeds of fire, to sweep
In a straight line unto one place, as 'twere,-
Casting them one by other, as they roll,
Into that onward course. Again, perchance,
In coming along, it pulls from out the air
Some certain bodies, which by their own blows
Enkindle its velocity. And, lo,
It comes through objects leaving them unharmed,
It goes through many things and leaves them whole,
Because the liquid fire flieth along
Athrough their pores. And much it does transfix,
When these primordial atoms of the bolt
Have fallen upon the atoms of these things
Precisely where the intertwined atoms
Are held together. And, further, easily
Brass it unbinds and quickly fuseth gold,
Because its force is so minutely made
Of tiny parts and elements so smooth
That easily they wind their way within,
And, when once in, quickly unbind all knots
And loosen all the bonds of union there.