The American Journal Analytical Chemistry is particularly interested in a type of smell: "A combination of grassy notes with a tang of acids and a hint of vanilla over an underlying mustiness".

It might sound for a moment like the description of a less than vintage wine, but this is the smell recognisable to anyone who spends much time in libraries: the smell of aging books.

But not all old books smell the same, at least not to the technological 'noses' that the scientists are working with.

The smells are created by the release of an extremely complex cocktail of hundreds of so-called volatile organic compounds into the air, partly depending on the original materials used to create the book (wood and chemicals used to make the paper, the binding etc).

The presence and intensity of particular VOCs gives a wealth of information on a "network of degradation pathways", the journal explains.

Previously, to assess the condition of a book or document at a chemical level, a sample of the piece would have to be removed, necessarily damaging it.

It's now hoped that the technology will give more opportunities to intervene if the work is deteriorating faster than is strictly necessary. By tracking the VOCs - especially 15 which have been picked out as good markers - the tomes can be preserved.

We currently have two books well worth preserving at Paul Fraser Collectibles: an autographed copy of Martin Luther King's Stride Toward Freedom, and the Bible which Robert Burns leafed through shortly before his death in 1796.