An atlas was recently returned to Trinity Hall’s Jerwood Library half a century after being checked out. Although the exact dates are not known due to a lack of surviving records, it was borrowed by an undergraduate at the college in the early 1970s.

At the average rate of 20p a day in library fines, the book’s late return fee would have been over £3,000.

The atlas was returned following a college reunion event with a note from the borrower explaining that it was of historical interest.

The head librarian later discovered that it was a rare 19th-century atlas published by the Society for the Diffusion of Useful Knowledge (SDUK), which was founded in 1826 by Whig politician Lord Henry Brougham.

Until it was disbanded in 1846, the society published on a variety of subjects for a working-class readership – its most successful publication was a set of atlas maps, to which the book belonged.

Trinity Hall’s head of library services, Jenni Lecky-Thompson, said: “Until the Society published their maps, atlases were expensive – luxury items intended for the gentleman’s library.

“The SDUK maps were intended to attract a wide readership and be affordable, and they are some of the most accurate and well-designed maps of the time.

“Trinity Hall’s atlas was published in around 1856 by George Cox. It contains over 160 engraved maps produced by J & C Walker. The maps reflect a time when the British Empire was expanding and people were interested in the colonial possessions in far-off lands.”

The book’s entries on Africa show large areas of empty space inside the continent, reflecting the limits of European understanding of Africa in the 19th century.