A newly discovered set of letters written by the poet Percy Bysshe Shelley are to go on sale after being found in a trunk at a house in London.
Percy Bysshe Shelley as portrayed by Oliver Chris in a BBC drama
The correspondence, written by Shelley and his friend and biographer Thomas Jefferson Hogg, was destined for a car boot sale before being identified.
The letters could fetch £30,000 when they go on sale at Christie's in June.
Shelley and Hogg were expelled from Oxford University in 1811 for writing a pamphlet about atheism.
Both men were summoned before the authorities when the article was circulated. Shelley refused to co-operate and Hogg protested.
The eight letters by the pair were written to Ralph Wedgwood, a member of the famous pottery family, and sheds light on Shelley's eventual emergence as a rebel poet and the theme of atheism in his work.
The writer, whose wife Mary created Frankenstein, attacked the church and said that "Christ never existed" in the letters, which throw new light on Shelley's intellectual development.
They were discovered at a house in Norbury, south-west London by one of Wedgwood's descendants, who decided to show them to an expert before taking them to a car boot sale.
Crispin Jackson, head of books at Christie's, said the letters, stowed away in a dusty trunk, were kept for the Wedgwood connection rather than their famous authorship.
Christie's valuable printed books and manuscripts sale on 8 June will also feature a copy of a letter from Christopher Columbus printed in 1494, announcing his entry into the New World.