Like a Thunder-Clap

Geoffrey Chaucer, Canterbury Tales 3798-3810 (The Miller's Tale), translated by Nevill Coghill:

Now Nicholas had risen for a piss,
And thought he could improve upon the jape
And make him kiss his arse ere he escape,
And opening the window with a jerk,
Stuck out his arse, a handsome piece of work,
Buttocks and all, as far as to the haunch.
Said Absalon, all set to make a launch,
'Speak, pretty bird, I know not where thou art!'

This Nicholas at once let fly a fart
As loud as if it were a thunder-clap.
He was near blinded by the blast, poor chap,
But his hot iron was ready; with a thump
He smote him in the middle of the rump.

In Middle English:

This Nicholas was risen for to pisse,
And thoughte he wolde amenden al the jape;
He sholde kisse his ers er that he scape.
And up the wyndowe dide he hastily,
And out his ers he putteth pryvely
Over the buttok, to the haunche-bon;
And therwith spak this clerk, this Absolon,
'Spek, sweete bryd, I noot nat where thou art.'

This Nicholas anon leet fle a fart
As greet as it had been a thonder-dent,
That with the strook he was almoost yblent;
And he was redy with his iren hoot,
And Nicholas amydde the ers he smoot.