The “Knocking on Wood” Wikipedia page mentions Roud’s conclusion, and this claim of a 19th century origin has circulated online as the final say on the matter. If you go back to the original, though, Roud’s proposal actually ends on an ambivalent note: “Before this theory [of 19th century origins] can be finally accepted, however, an examination of the history of European forms of this custom would be advisable.”
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Цены на нефть взлетели до максимума за полгода17:55，更多细节参见旺商聊官方下载
"What we have found is certain weeks during the year there'll be a hundred bats in here, and then suddenly they will disappear," says Parker.