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I had always heard that I had always heard that theory as well. However,  the US Library of Congress "Everyday Mysteries" site , claimedd it was a false theory. Thatch roofs were tightly woven, water resistant, and sharply pitched. "In order to slip off the roof, the animals would have to be lying on the outside—an unlikely place for an animal to seek shelter during a storm." Bah! I love the thought of cats and dogs bouncing around on top of a canopy bed.

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