Egypt's ancient Library of Alexandria is often said to have burned, but its books faced a slower danger. They were papyrus scrolls, a plant-based paper, kept in a seaside city where humid air makes papyrus rot.
Mold, insects and mice could ruin a scroll. The only defense was copying each text by hand onto a new scroll.
Some historians think the library died of neglect: when the copying stopped, the scrolls slowly fell apart.