A book of Edward Lear's limericks that comedian Ronnie Barker changed to make funnier is tipped to sell for around £1,500 at auction.
The much loved Porridge star took his pen to Lear's The Book of Nonsense after apparently being disappointed by the poet's comic ability.
Barker, who died in 2005, was unimpressed that Lear's limericks often featured the same word at the beginning and end of the poem.
The Two Ronnies funnyman created his own ode to the 19th century poet, writing an introductory limerick in the book:
"There was an old fossil named Lear, Who's (sic) verses were boring and drear, his last lines were worse - just the same as the first!
"So I've tried to improve on them here."
The ditty's first two lines feature overwriting due to a malfunctioning pen, and the piece was signed by Barker and dated November 2001.
The 39th edition of The Book of Nonsense comprises 112 illustrated limericks by Lear.
All but the frontispiece limerick were annotated by Barker and the majority saw him cross out Lear's last line and replace it with his own.
Barker, who died aged 76, kept the nation laughing for years with his brilliant linguistic ability and with partner Ronnie Corbett created countless skits and clever jokes based on puns and play on words.
Among his most celebrated was the fork handles (four candles) sketch in which Corbett plays a baffled shopkeeper exasperated by Barker's ambiguous shopping list.
Lear, perhaps most famous for his Owl And The Pussycat poem, left Barker unimpressed.
Examples of the changes include: "There was an Old Man of the Dee, who was sadly annoyed by a flea; When he said 'I will scratch it', they gave him a hatchet, which grieved that Old Man of the Dee," - which Barker altered to: "And cut his leg off at the knee."
The book is being sold at the Dominic Winter saleroom, near Cirencester, Gloucester, on 21 June.
The book is described on the auctioneer's website as: "An extraordinary and unique item, associating two British masters of comic language and wordplay.
"Lear's limericks were truly nonsensical and mostly devoid of punchlines or any point, the first and last lines usually ending with the same word rather than a new rhyming one.
"Nonetheless, Lear's book, first published in 1846, helped popularise the form which later became standardised in five lines with a humorous new rhyming last line often acting as a punchline.
"The pen used by Barker is the same throughout, suggesting that this was a minor diversion carried out in a short space of time, rather than a serious project to come up with the best possible final line.
"Certainly, the final initialled limerick suggests that he had had enough by the time he got to the end: 'There was a Young Lady of Clare, who was sadly pursued by a bear; When she found she was tired, she abruptly expired, And so do these rhymes - in despair!'"