Books are not really as flammable as they may seem. A book is a dense thing, layer upon layer of pulped wood stacked and pressed together. Air does not circulate easily within a book, and a flame needs air to survive.
Hold a match to a book and the edge of the text block will singe and char but it will not spontaneously burst into flame. The flame will probably self-extinguish. It’s a bit like trying to set fire to a log without any kindling. Cotton fabric also self-extinguishes, which is one reason why it’s recommended for children’s clothing. Cellulose is the base material of both wood-pulp paper and cotton cloth.
Nevertheless, as we all know, books do burn — if the flames (and pages) are fanned. Books have been burned countless times throughout our history, as a way of condemning philosophies, religions, types of people. Entire libraries and archives have been lost due to fire, from the great library at Alexandria to the personal collections of those affected by the Black Saturday bushfires.
The philosopher Seneca wrote that 40,000 books were burned at Alexandria but no record of the library’s holdings survives. It is impossible to know for sure how much or what was lost. It is not even certain how and when the library was burned. Four possible occasions have been identified for either its partial or complete destruction: the fires set by Julius Caesar in the Alexandrian War of 48 BC, during Emperor Aurelian’s attack on the city in 270-275 BC, after a decree of the Coptic Pope Theophilus in AD 391 that required the sites of previously pagan temples to be destroyed, or during the Muslim conquest of Alexandria in about 642 BC.
The books in Alexandria’s great library would mostly have been scrolls written on papyrus, a writing material made from beaten reeds. The library largely predated parchment (untanned animal skin) although apparently it contributed to the development of this new writing material due to the huge demand it placed on suppliers of papyrus. It was said that any book arriving through the port of Alexandria was copied by the library’s scribes, in what could be thought of as a kind of an ancient version of the Google Books project. It was rumoured that the copies were so good that sometimes the copy was returned to the unsuspecting owner and the original retained.
Trying to retrieve burned books and documents is not a pleasant task. If not completely destroyed, books and boxes or records will be charred along their edges but text in the centre of the pages will still be readable. They will be brittle. They will stink. They will shed black particulates onto every surface. They may also be wet, due to fire-fighting activities. One actually wishes they had been totally destroyed so one did not now have to attempt to save what was left.
Apart from vacuuming away the soot and copying any remaining information, any other kind of stabilization treatment is horribly laborious and usually unsatisfactory. If new copies cannot be found, many decide to just put the damaged material into storage, only retrieving a box or a book for treatment when someone finally decides they want to see it.