Bats in the biblioteca offer unusual role for rolls of leather
One of the most spectacular libraries in the world, the Biblioteca Joanina at the University of Coimbra in Portugal, owes its ability to preserve and keep on display books from as long ago as the fifteenth century partly to bats.
Coimbra claims to have one of the oldest still-functioning universities in Europe, with its first lectures taking place in 1290. In the course of its early history, it moved back and forth several times between Lisbon and Coimbra, before becoming permanently established in the smaller city in 1537.
The Johannine Library is a later addition, with the building of it beginning in 1717 under the auspices of King John V (hence the name) who wanted the university’s by-now large (70,000 volumes) and venerable collection of books to have a suitable home; the king was a renowned bibliophile.
It’s common to find leather in libraries, especially those that store ancient books; these precious objects are, naturally, usually leather-bound. In addition to this, though, leather has an unusual extra role to play in Coimbra’s case.
At least two distinct colonies of bats are known to inhabit the library, coming out at night when the visitors have gone. Their voracious appetites and expertise in catching insects combine to keep the books from suffering serious damage from pests.
However, the same hearty appetites also lead to deposits of bat droppings, which library staff have to clean every morning when the bats’ work is done. To keep the handsome, long wooden tables from coming to any harm, one of the last jobs the staff perform in the evening is to unroll protective sheets of soft, cognac-coloured leather and place them over the tables, grain-side-up.
The leather is easier to clean and replace than the tables.
