Ha! There's one of those "Why didn't I think of that?" ideas.

Wood ash combines with water to create lye. And as I learned this summer staying in a campsite with 30 other people, they use lye to kill the stench in pit toilets. Adding wood ash is a great idea.
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A gentleman should always be able to break his fast in the manner of a gentleman where so ever he may find himself.--Good Omens