Sir Arthur Conan Doyle was born in Edinburgh in 1859
A book handed into an Oxfam shop which contained the first Sherlock Holmes stories is set to be sold for £9,000.
Study in Scarlet, which features Sir Arthur Conan Doyle's first two Holmes tales, was donated to a Harrogate, North Yorkshire, branch of the charity.
It will be the star lot in an auction made up of books given to Oxfam shops at Bonhams in Oxford on 20 May.
Other lots include a first edition Harry Potter and the Chamber of Secrets listed to sell for £500.
Simon Roberts, of Bonhams books, said: "It is extraordinary what emerges from these Oxfam shops.
"It is a snapshot of what people have read and collected over the past century.
"Some of these books have been handed in with little knowledge of their value."
The collection also includes first editions of The Jungle Book by Rudyard Kipling, Sons and Lovers by DH Lawrence and CS Lewis's The Voyage of the Dawn Treader.