“Remedies such as Uraca’s may have hurt, but most of them would not have done any lasting damage. Given the risks involved, however, the consistency with which spices were applied to the eyes is nothing less than astonishment. Pepper salves appear in Greek medical manuscripts of the 5th century, mixed with copper, saffron, opium, lead, and calamine. Pedro Hispano, later Pope John XXI (ca 1215–77), author of one of the most widely consulted medical works of the Middle Ages, Universal Diets and Particular Diets, claimed that “Pepper is good for dimmed eyes.” For “dimness of the eyes” the early 11th century Anglo-Saxon manuscript known as the Herbarium of Apuleius suggests obscurely but alarmingly, a poultice made of ground celandine, honey, pepper and wine with direction “smear the eyes inwardly.” The thinking seems to have been that just as bleeding drew off ill humors from the blood, so provoking tears drained off the ill humors of the eye, warming and drying the wet and runny eye of superfluous fluid. More likely they simply caused unnecessary damage. The accumulated authority of medical tradition overruled observation. (

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Challenging notion: One of the reasons the lens remains transparent is …