Readers of the later Middle Ages enjoyed satires. The late 12th-century 'Speculum Stultorum' ('Mirror of Fools') was one of the most enduringly popular, mentioned by Chaucer in the 'Canterbury Tales' (''Nun's Priest's Tale') and published continuously into the 16th century. A certain Nigel (aka Wireker), a monk of Christ Church, Canterbury, wrote the story of a mule from Cremona named Brunellus. Feeling inferior because of his short tail, Brunellus tries to compensate by over-achieving. He goes off to university in Paris but fails after years of study. His quest for status leads him to start a new religious order, but soon his master finds him and takes him back to Cremona. Brunellus remains convinced that he will be famous. Writing in verse with high-flown metre, Wireker targets the contemporary behaviour of students and religious orders. This copy was probably made around the 1420s, by John Streech, canon of the Augustinian Priory of Kenilworth. Wireker's prose introduction is at the top, with the name of Willlemus, to whom he addressed it, highlighted in red. Willemus is thought to be William Longchamp, later the Bishop of Ely. The verse prologue is flanked by the heads of two unkempt monks, probably intended to mirror each other as fools in view of Wireker's explanation of Brunellus as an ambitious, discontented monk.