What hides this stereogram?

Sir Bedevere:

'Now, why do witches burn?'

Peasant:

'...because they're made of... wood?'

Sir Bedevere:

'Good. So how do you tell whether she is made of wood?'

Peasant 2:

'Build a bridge out of her.'

From Monty Python and the Holy Grail

Picture: Rex Features