there is a scene where Puddleglum the Marsh-Wiggle puts out a fire by stamping on it with his foot, thereby dampening the magic spell the witch has them under. After it was written, a friend of his pointed out that a wood fire wouldn't go dark after stomping on it, but would continue to glow.
Lewis then considered making it a peat fire, but couldn't remember if peat would glow after stomping (and was embarrassed, he later said, as an Irishman, to not know that). He considered charcoal, but decided that wood and peat and charcoal were no good as the people of the Underworld would have to import them. So he decided on coal, but then ultimately when the book was published, simply described the whole thing as "a fire" without getting into what was burning.
*The radio productions themselves are pretty enjoyable; I am listening to them on CD. BUT, the voice of Aslan is among the top-10 most annoying things I have ever heard on radio or TV. It doesn't quite replace that little girl from The League, but it is VERY close. (The little girl from The League might be beaten out by that annoying eHarmony grand-daughter with the fake babytalk, though.)**
**I got a little off track here. Sorry.
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