When you speak of bad luck, it is said that one should always knock on wood. Also knocking when speaking of good luck apparently helps with having good luck. This is an old Celtic tradition related to belief of wood spirits.
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An acorn at the window will keep lightning out
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Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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At times, a horseshoe may be found above doorways. When positioned like a regular 'U' it supposedly collects luck. However, when it is positioned like an upside-down 'U' the luck supposedly drains.
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If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
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In some parts of England, rum is used to wash a baby's head for good luck.
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An acorn should be carried to bring luck and ensure a long life.
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It's bad luck to leave a house through a different door than the one used to come into it.
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