A rare copy of Charles Darwin's "On the Origin of Species" picked up an impressive bidding price of £26,000 in an auction on Wednesday.

The item is a rare first edition of the book that was published in 1859, and was sold as part of an auction from the library of popular author Lady Mary Stewart. The auction took place at Lyon & Turnbull's Edinburgh auction rooms.

Originally valued between £15,000 and £25,000, this copy of the book is "good condition," Lyon & Turnbull's Simon Vickers told The Mirror.

"We sold a copy about five years ago that made £12,000 but this one has been repaired and rebacked and is in good condition," Vickers added.

Vickers stated that the "On the Origin of Species" is widely recognised by scientists as the most important publication on the theory of evolution, championed by the book's author Darwin.

"This is the book in which Darwin prepared his theory. The book is probably the most important biological breakthrough in the 19th century," Vickers said of the book's value to science. "It has affected the study of biology and is a very important textbook."

"It is one of the most important scientific books written ever," Vickers concluded.

Charles Darwin theorised that all species of life have descended over time from common ancestors.  He developed his theory while he was journeying to the Galapagos Islands in South America on board the HMS Beagle, a vessel that author Lady Stewart's great grandfather sailed on.

According to the Shropshire Star, Lady Mary Stewart explained in a letter that she added the "On the Origin of Species" to her library because of the connection with her great-grandfather. The letter was mailed to a London bookseller.