My last post talked about Rapunzel’s Syndrome, in which unfortunate sufferers eat their own hair. Since hair cannot be digested, a mass forms in the patients’ stomachs, often requiring surgery. There is a fascinating but gruesome silver lining to situations such as these, however, which is that sometimes these masses can congeal and take shape into a new object, one that maybe resembles a rock smoothed over by the pounding of water. These “rocks,” in Medieval and Early Modern Eurasia, were called “bezoars,” (from the Persian “pad-zahr” or “antidote”) and they were sought-after objects thought to have magical properties of curing poison. Bezoars might be made up of a variety of indigestible material in the gut, but this image of a bejeweled bezoar from the Habsburg Dynasty dating from 1600 shows just how seriously they were taken. Surprisingly, studies undertaken with compounds of arsenic showed that indeed, bezoars could neutralize this particular poison. (Not others. The neutralization has to do with the way the bezoar interacts with either sulphur or phosphate.)