An Australian public library has finally welcomed back a book that was estimated to be 150 years overdue, along with a potential A$28,000 ($19,500) late-return fine. The catch? The library has no way of finding the borrower who originally checked it out.150-year-old book found inside a fireplaceThe book, “Antiquities of Athens,” was published in 1858 and was returned to Kiama Library in the seaside town of Kiama last week.ALSO READ: Michigan cyclosporiasis outbreakA man discovered the book during recent home renovations, tucked inside a tea crate that had been bricked into a sealed fireplace, according to Kiama Library manager Michelle Hudson.“We’ve never had anything that old come back to us,” Hudson said.The finder did not immediately respond to The Associated Press’s request for comment.“I follow lots of libraries on social media and often you’ll get things that are maybe 30 or 40 years old when they’re cleaning out estates and stuff like that,” she added.ALSO READ: Quote of the Day by Julius CaesarThe overdue fine would be $19,500The potential late-return bill is almost as remarkable as the book’s journey.Hudson said the fine would be around A$28,000 ($19,500) after accounting for inflation. It was calculated using the British three pence-a-week overdue fee printed inside the book.The same page also contained library rules that were in place when Kiama Library opened in 1872. But the library cannot collect the money because its records no longer reveal who borrowed the book.ALSO READ:Massachusetts farm installs 832 solar panels above berry fields, and the berries grown underneath turned out sweeter and juicier and could change the future of American farmingThe borrower has vanished from historyThe library’s journal from the 1870s recorded who borrowed books and when, but that journal has been lost.“Unfortunately, we have a missing link. There’s nothing in the book that tells us who the last borrower was,” Hudson said.The rules of the time required borrowers to return a book and pay any overdue debt before borrowing another one.“Maybe that’s why they never returned it to us,” Hudson said.Library rules were very different in the 1870sThe old rules also reveal just how different public libraries once operated.Households could borrow up to three books if at least six members were “known to be able to read.” Today, library users do not have to prove they can read before using the service.Another rule stated that books could not be lent to people who arrived at the library in a “state of intoxication.”Modern library users can still be asked to leave if their behavior affects others, but today’s rules are not specifically focused on intoxication.Book marked No. 506 will never be lent again“Antiquities of Athens” was marked No. 506 and came from Kiama Library’s original collection of around 1,000 books.The book has some water damage from its years under a chimney, and Hudson believes it was probably lost within only a few years of the library opening.Now, after an estimated 150-year absence, the book has finally returned — but it will not be going back onto the lending shelves.It will instead be displayed in the library’s local history collection.“We’re not going to allow it to go back out again. We don’t want to wait another 150 years for this book to be returned,” Hudson said.