The River Molecule by Christopher Lau (published 1997 in the Kimberlins anthology of creative work)

The river molecule always philosophizes.
He thinks thoughts like,
"Where is my source?
what happens after the river?" and
"is there really an ocean and air?"
He relentlessly questions other's visions of vapour.
"Does it really rain?" he would tell the other molecules.
Then on one unfortunate day, he was knocked onto shore;
and yet he still continued to criticize and philosophize!
"Why did that boulder just knock me ashore?" he remarked.
As usual, he frowned when he thought that he had heard an evil sound,
while the vapour smiled when he thought that he heard a benign sound:

gravity's laughter.
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