> Each night, workers cover the "buffets" (credenzas) with sheets of leather. In the morning the library is cleaned of bat guano [0] [0] https://en.wikipedia.o

> Each night, workers cover the "buffets" (credenzas) with sheets of leather. In the morning the library is cleaned of bat guano [0] [0] https://en.wikipedia.org/wiki/Biblioteca_Joanina#cite_note-WSJ-7:~:text=Bats%5Bedit%5D,guano.%5B7%5D https://en.wikipedia.org/wiki/Biblioteca_Joanina#cite_note-W...