The Persistence of Sound, by Charles Harper Webb

A word is dead / When it is said, / Some say.

Sounds never die, some scientists say.
They fade from hearing, but keep rolling up
and down -- smaller and smaller waves -- forever.
Churchill orating, "We will never surrender,"
Nixon whining, "I am not a crook,"
Caruso singing Vesti la giubba,
Savanarola screaming "I want a hat
of blood!" -- the right machine might amplify
the air-squiggles their voices made,
pluck them like worms from a wriggling pot.

I'd love to hear my dad ask Mom to marry him.
What did they sound like, conceiving me?
(Dad yelled, Mom whimpered, is my guess;
I'd love to be surprised.) I'd love to hear
Demosthenes's Greek, and the first Indo-European,
and what those Caucasians spoke
who left their perfect mummies in Xianping.
Anthropologists could hear the first human
step onto North America and know,
by plotting sound-decay, exactly when.

The air could prove a treasure trove dwarfing
Pompeii (Vesuvius still thundering;
Romans shrieking, buried alive.) Still, I hope
some sounds didn't survive: You poison me!
I picture Kevin when I come with you!
Maybe sound slops up and down just briefly,
then is cancelled out.  Otherwise,
someday we'll buy tapes of Jurassic birds,
of trees toppling in forests with no one to hear,
the crash retained in air the way a gold
bracelet torn by a Viking off an Irish
arm and melted down, retains traces
of serpent form, and the soft freckled skin
that warmed it, that the girl passed down to me --
the way a pterosaur's atoms (returned
to earth, re-used over and over) retain
in their vibrations every fish it ate, the squawks
it made feeding its young, the splash
when its heart -- so like mine -- stopped
and dropped into the undulating sea.

(Source: Verse & Universe: Poems about Science and Mathematics, Edited by Kurt Brown, 1998)