BEDOFNAILS
Bed of nails
A bed of nails is an oblong piece of wood, the size of a bed, with nails pointing upwards out of it. It appears to the spectator that anyone lying on this "bed" would be injured by the nails, but this is not so. Assuming the nails are numerous enough, the weight is distributed between them such that the pressure exerted by each nail is not enough to break the person's skin.The above text is a snippet from Wikipedia: Bed of nails
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