The book, which was first printed in 1859, was bought by a family for just a few shillings in a shop about 40 years ago, Christie's auction house said.Well, at least they were reading it.
The family has since kept the work on a bookcase in the guest lavatory at their home in the Oxford area, it said.
The book will go under the hammer in London on Tuesday, to coincide with the 150th anniversary of the publication of the father of the theory of evolution's famous work.
The book, about 1,250 copies of which were first printed, is expected to fetch STG60,000 ($A108,254).
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