GOOD QUESTION:

Bless This Boggy Book
How do bogs keep things fresh?
By Daniel Engber (Slate Explainer column)
Posted Friday, July 28, 2006, at 6:50 PM ET

A construction worker discovered an ancient book of psalms while excavating an Irish bog last Thursday. Ireland's National Museum has called it "a miracle find" and labeled the 1,200-year-old tome the "Irish equivalent to the Dead Sea Scrolls." How could the book have survived for so many years in a bog?

European peat bogs happen to be excellent at preserving organic matter. Bits of animal skin—like the vellum pages upon which the ancient psalter was written—can last for hundreds or thousands of years when they get trapped under the surface of peat at the top of a bog. That's because they're exposed to an acidic environment with lots of sphagnum moss and very little oxygen. These factors make life very hard for the microbes that would otherwise cause rotting and decomposition.

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