A book on Greek antiquities has been returned to an Australian public library approximately 150 years after it was borrowed, bearing water damage from its time sealed within a fireplace.

Ross Simmons discovered the book, titled "Antiquities of Athens," during recent renovations at his home in Kiama. It was found inside a tea crate that had been bricked into a sealed fireplace. The volume, published in 1858, was part of the Kiama Library's original collection of about 1,000 books and was marked as No. 506.

Library manager Michelle Hudson stated that the library, which opened in 1872, had never received a return of an item so old. Hudson suspects the book was lost within a few years of the library's opening.

Simmons believes the book may have been borrowed by his great-great-grandfather, John Simmons, who resided in the house around the time the library was established. "I'm making an assumption. He was in residence in the cottage around about that time and his children were probably too young," Ross Simmons said.

Based on the book's internal markings, which detailed a British overdue fee of three pence per week, the library calculated that the late return fine, adjusted for inflation, would be approximately 28,000 Australian dollars (about $19,500).

However, library records from the 1870s are missing, preventing identification of the last borrower. Hudson noted that library rules at the time stipulated that overdue debts had to be settled before another book could be borrowed, speculating this might have contributed to the book's non-return.

Historical library rules also included restrictions such as requiring households to have at least six members capable of reading to borrow up to three books, and prohibiting loans to individuals in a "state of intoxication." Modern library policies have evolved, with current rules addressing disruptive behavior without specific mention of intoxication.

Simmons, 77, expressed no concern about potential liability for the family's historical debt.

The returned book is slated for display within the library's local history collection and will not be available for circulation to prevent another extended absence.