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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A single magpie is considered a sign of bad luck. A Guide to the Scientific Knowledge of Things Familiar recites an old proverb concerning the incidence of bad weather when magpies forage alone and a possible scientific explanation for this.
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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 one walks underneath an open ladder it is said to bring bad luck. Sometimes it is said that this can be undone by immediately walking backwards back underneath the ladder.
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Amber beads, worn as a necklace, can protect against illness or cure colds.
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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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In some parts of England, rum is used to wash a baby's head for good luck.
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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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