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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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
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Placing keys on a table is considered unlucky. (Sweden)
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Pirates believed that piercing the ears with such precious metals as silver and gold improved one's eyesight.
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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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Opening an umbrella indoors is said to result in 21 days of bad luck. Some traditions hold that it is only bad luck if the umbrella is placed over the head of someone while indoors.
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