Altarpiece of Saint Cosmas and Saint Damian (The Sick Sacristan). Twin brothers born in Syria, these Christian saints, martyred c 303, were skilled physicians and surgeons and are shown attending a patient. Legend says they transplanted a leg from a corpse onto a patient with an ulcerated leg. Sano di Pietro Di Menico (or Ansano 1406-1481). Painting on panel.