The Moon and a physician holding a urine jar with three patients. Leonardo de Piero Dati, La sfera. Wellcome Library MS 230 (mid 15th century), f.4r
The Moon’s qualities are cold and moist. In alchemy it is associated with the metal silver. The children of the moon are fools, magicians and fishermen. The moon was important in medieval medicine because it was believed to control the blood in the body in a similar way to governing the tides of the sea.